15 June 1962

General List No. 45

international Court of Justice

Temple of Preah Vihear

Cambodia

v. 

Thailand

Judgement

[p.6]

The Court,

composed as above,

delivers the following Judgment:

By its Judgment of 26 May 1961, the Court rejected the first preliminary objection of the Government of Thailand and found that it had jurisdiction to adjudicate upon the dispute submitted to it on 6 October 1959 by the Application of the Government of Cambodia.

By Order of the same date, the Court fixed the time-limits for the further pleadings. The case became ready for hearing on the filing of the last pleading on 2 February 1962.

Public hearings were held on the following dates: 1-3 March, 5 March, 7-10 March, 12-13 March, 15-17 March, 19-24 March and 26-31 March 1962. At these hearings the Court heard oral argu-ments and replies by M. Truong Cang, Mr. Dean Acheson, M. Roger Pinto and M. Paul Reuter on behalf of the Government of Cambodia, and by Prince Vongsamahip Jayankura, Mr. Seni Pramoj, M. Henri Rolin, Sir Frank Soskice and Mr. James Nevins Hyde on behalf of the Government of Thailand.

At the hearings from 15 to 20 March 1962, the Court heard the evidence of the witnesses and experts, called by each of the Parties, in reply to questions put to them in examination and cross-exami-[p 9]nation on behalf of the Parties and by Members of the Court. The following persons gave evidence:

called by the Government of Cambodia:

M. Suon Bonn, former Governor of Kompong Thorn, Inspector of Political and Administrative Affairs in the Ministry of the Interior of Cambodia, as witness;

called by the Government of Thailand:

Professor Willem Schermerhorn, Dean of the International Training Center for Aerial Survey, Delft, and Director of the Consulting Department of the Center, as expert;

Mr. Friedrich E. Ackermann, Dipl. Ing., Lecturer at the International Training Center for Aerial Survey, Delft, and member of the Consulting Department of the Center, as witness and expert;
Mr. Herman Theodoor Verstappen, geomorphologist, Head of the Geological Section of the International Training Center for Aerial Survey, Delft, as expert.

At the hearing held on 19 March 1962, the Court withdrew and reassembled in private to attend, in the presence of the representatives of the Parties, the showing of a film of the place in dispute filed by Cambodia. During the projection of the film and with the authorization of the President, M. Suon Bonn gave brief indications relating to points of fact.

In the course of the written proceedings, the following Submissions were presented by the Parties:

On behalf of the Government of Cambodia,

in the Application and in the Memorial:

"May it please the Court to adjudge and declare, whether the Kingdom of Thailand appears or not:
(1) that the Kingdom of Thailand is under an obligation to withdraw the detachments of armed forces it has stationed since 1954 in the ruins of the Temple of Preah Vihear;
(2) that the territorial sovereignty over the Temple of Preah Vihear belongs to the Kingdom of Cambodia";

in the Reply:

"May it please the Court:

I.—To reject the submissions presented by the Kingdom of Thailand in its Counter-Memorial, subject, in particular, to the presentation, if necessary, of any other grounds for the rejection of any further submissions that may be presented by the Kingdom of Thailand;

II.—To find in favour of the submissions contained in its Application instituting proceedings and in its Memorial.

To adjudge and declare [p 10]

I.—That the Kingdom of Thailand is under an obligation to withdraw the detachments of armed forces it has stationed since 1954 in the ruins of the Temple of Preah Vihear;

2.—That the territorial sovereignty over the Temple of Preah Vihear belongs to the Kingdom of Cambodia."

On behalf of the Government of Thailand,

in the Counter-Memorial:

"The Government of Thailand submits:
(1) that the claims of the Kingdom of Cambodia formulated in the Application and the Memorial are not sustainable and should be rejected;
(2) that Phra Viharn is in Thai territory: and the Court is respectfully asked so to adjudge and declare."

During the oral proceedings, Counsel for Thailand asked, at the close of the hearing of 13 March 1962, to be allowed to defer formulating the Final Submissions on behalf of Thailand until after the evidence of witnesses and experts. The Agent for Cambodia was requested to express his views on the matter and declared that he relied entirely on the justice and wisdom of the Court. The Court, after having deliberated, granted the authorization requested, it being understood that, after the evidence of witnesses and experts and before the filing of the Final Submissions of Thailand, the Agent for Cambodia might file such modifications to his own Submissions as he wished to make after having heard the evidence.

The Submissions presented by the Parties during the oral proceedings and in particular after the foregoing decision were as follows:

On behalf of the Government of Cambodia:

A. Submissions read at the hearing of 5 March 1962

"May it please the Court:
1. To adjudge and declare that the frontier line between Cambodia and Thailand, in the Dangrek sector, is that which is marked on the map of the Commission of Delimitation between Indo-China and Siam (Annex I to the Memorial of Cambodia);

2. To adjudge and declare that the Temple of Preah Vihear is situated in territory under the sovereignty of the Kingdom of Cambodia;

3. To adjudge and declare that the Kingdom of Thailand is under an obligation to withdraw the detachments of armed forces it has stationed since 1954, in Cambodian territory, in the ruins of the Temple of Preah Vihear;

4. To adjudge and declare that the sculptures, stelae, fragments of monuments, sandstone model and ancient pottery which have been removed from the Temple by the Thai authorities since 1954 are to be returned to the Government of the Kingdom of Cambodia by the Government of Thailand." [p 11]

B. Submissions, entitled Final Submissions, read at the hearing of 20 March 1962

"May it please the Court:

1. To adjudge and declare that the map of the Dangrek sector (Annex I to the Memorial of Cambodia) was drawn up and published in the name and on behalf of the Mixed Delimitation Commission set up by the Treaty of 13 February 1904, that it sets forth the decisions taken by the said Commission and that, by reason of that fact and also of the subsequent agreements and conduct of the Parties, it presents a treaty character;

2. To adjudge and declare that the frontier line between Cambodia and Thailand, in the disputed region in the neighborhood of the Temple of Preah Vihear, is that which is marked on the map of the Commission of Delimitation between Indo-China and Siam (Annex I to the Memorial of Cambodia);

3. To adjudge and declare that the Temple of Preah Vihear is situated in territory under the sovereignty of the Kingdom of Cambodia;

4. To adjudge and declare that the Kingdom of Thailand is under an obligation to withdraw the detachments of armed forces it has stationed, since 1954, in Cambodian territory, in the ruins of the Temple of Preah Vihear;

5. To adjudge and declare that the sculptures, stelae, fragments of monuments, sandstone model and ancient pottery which have been removed from the Temple by the Thai authorities since 1954 are to be returned to the Government of the Kingdom of Cambodia by the Government of Thailand."

On behalf of the Government of Thailand:

A. Submissions read at the hearing of 20 March 1962
"With respect to the Submissions presented by the Government of Cambodia on the 5th March, 1962, the Government of Thailand respectfully presents the following as its Submissions to the Court:

1. The Court is asked not to entertain the claims put forward by Cambodia in paragraphs 1 and 4 of the Submissions presented on Monday, 5th March, by the Agent for the Government of Cambodia, on the ground that both those claims are put forward too late and were not included as claims which the Government of Cambodia wished to present to the Court in the Application instituting these proceedings or in the course of the written pleadings and were for the first time put forward by the Agent for Cambodia when he formulated Cambodia's conclusions.
It is therefore submitted that these claims should not now be entertained by the Court.

2. Alternatively,

In regard to the first of the said claims Thailand submits the following conclusions:

(i) The map Annex I has not been proved to be a document binding on the Parties whether by virtue of the Treaty of 1904 or otherwise. [p 12]
(ii) Thailand and Cambodia have not in fact treated the frontier marked out on Annex I as the frontier between Thailand and Cambodia in the Dang Rek region.
(iii) For the above reasons, the frontier line marked on Annex I ought not to be substituted for the existing boundary line in fact observed and accepted by the two Parties in the Dang Rek range.
(iv) Even, therefore, if the Court, contrary to the submission of Thailand, thinks it proper to entertain the said claim (r) now put forward by Cambodia, Thailand submits that on the merits this claim is not well founded and ought to be rejected.

3. Thailand submits the following further conclusions in answer to Submissions 2 and 3 put forward by Cambodia:

(i)Abundant evidence has been given that at all material times Thailand has exercised full sovereignty in the area of the Temple to the exclusion of Cambodia. Alternatively, if, which is denied, Cambodia in any sense carried out any administrative functions in the said area, such acts were sporadic and inconclusive, and in no sense such as to negative or qualify the full exercise of sovereignty in the said area by Thailand.
(ii) The watershed in the said area substantially corresponds with the cliff edge running round Phra Viharn and constitutes the treaty boundary in the said area as laid down by the Treaty of 1904.
(iii) To the extent that the cliff edge does not precisely correspond with the watershed as shown by the configuration of the ground in the area, the divergencies are minimal and should be disregarded.
(iv) The general nature of the area allows access from Thailand to the Temple, whereas access from Cambodia involves the scaling of the high cliff from the Cambodian plain.
(v) There is no room in the circumstances of the present case for the application in favour of Cambodia of any of the doctrines prayed in aid by Counsel for Cambodia, whether acquiescence, estoppel or prescription.
(vi) Cambodia ought not in any event now to be allowed by the Court to put forward a claim based on prescription not having anywhere in her pleadings or until the very end of her oral argument put forward any such claim.
(vii) The evidence in favour of Cambodia is in any event wholly inadequate to support any prescriptive title in Cambodia.

Cambodia's second and third Submissions ought therefore to be rejected.

4. Further and in the alternative with regard to Cambodia's fourth Submission, it is submitted that this Submission, even if entertained by the Court, is wholly unsupported by evidence, and the claim put forward by Cambodia in its fourth Submission is accordingly unsustainable." [p 13]

B. Revised Submissions presented on 20 March 1962 after the hearing

"With respect to the revised Submissions presented by the Government of Cambodia on the 20th March 1962, the Government of Thailand respectfully submits the following Submissions to the Court:

I. With regard to the first claim of the revised Submissions:

1. The whole of the evidence before the Court shows that the map of the sector of the Dang Rek which is Annex I to the Memorial of Cambodia was not prepared or published either in the name or on behalf of the Mixed Commission of Delimitation set up under the Treaty of the 13th February, 1904; but, whereas the said Mixed Commission consisted of a French Commission and a Siamese Commission, the said Annex I was prepared by members of the French Commission alone and published only in the name of the French Commission.

2. The French officers who prepared the said Annex I had no authority to give any official or final interpretation of the decisions of the said Mixed Commission, still less of the intentions of the said Mixed Commission at points at which no decision had been recorded.

3. No decision of the said Mixed Commission was recorded about the boundary at Phra Viharn. If the said Mixed Commission did reach such a decision, that decision is not correctly represented on the said Annex I, but was a decision that in the Phra Viharn area the boundary should coincide with the cliff edge.

4. There was no subsequent agreement of the parties attributing a bilateral or conventional character to the said Annex I.

5. The conduct of the parties, so far from attributing any conventional character to the said Annex I, shows that the Parties have not treated the line marked on the said Annex I as the boundary in the Dang Rek; Thailand has remained in undisputed possession of all the territory at the top of the Dang Rek. Wherever there is a cliff edge in the Dang Rek the edge of the cliff is, and has been, accepted as constituting the watershed boundary established in this region by Article I of the said Treaty of 1904.

6. Even if the said Annex I were to be regarded as possessing a conventional character, the boundary line marked on it would not be binding on the parties when proved—as it has been in the disputed area—to be based on an inaccurate survey of the terrain.

II. With regard to the second claim of the revised Submissions: 1. The Court is asked not to entertain the claim, because:

(i) the claim to a region 'in the neighbourhood of the temple of Phra Viharn' constitutes an enlargement of the claim presented by the Government of Cambodia in the Application instituting these proceedings and throughout the written pleadings; [p 14]
(ii) the terms of the claim are too vague to allow either the Court or the Government of Thailand to appreciate what are the limits of the territory claimed.

2. Alternatively, the Government of Thailand repeats paragraph 3 of its submissions presented at the sitting of the Court on the 20th March, 1962.

III. With regard to the third and fourth claims of the revised Submissions:

The Government of Thailand repeats paragraph 3 of its submissions presented at the sitting of the Court on the 20th March, 1962.

IV. With regard to the fifth claim of the revised Submissions:

1. The Court is asked not to entertain this claim, because it constitutes an enlargement of the claim presented by the Government of Cambodia in the Application instituting these proceedings and throughout the written pleadings.

2. Alternatively, the rejection of the first, second and third claims of the revised Submissions must involve the rejection of this claim.

3. Alternatively, this claim should be restricted to any objects of the kinds specified in the claim proved by the evidence before the Court to have been removed from the temple since 1954 by the Thai authorities."

***

In its Judgment of 26 May 1961, by which it upheld its jurisdiction to adjudicate upon the dispute submitted to it by the Application filed by the Government of Cambodia on 6 October 1959, the Court described in the following terms the subject of the dispute:
"In the present case, Cambodia alleges a violation on the part of Thailand of Cambodia's territorial sovereignty over the region of the Temple of Preah Vihear and its precincts. Thailand replies by affirming that the area in question lies on the Thai side of the common frontier between the two countries, and is under the sovereignty of Thailand. This is a dispute about territorial sovereignty."

Accordingly, the subject of the dispute submitted to the Court is confined to a difference of view about sovereignty over the region of the Temple of Preah Vihear. To decide this question of territorial sovereignty, the Court must have regard to the frontier line between the two States in this sector. Maps haven been submitted to it and various considerations have been advanced in this connection. The Court will have regard to each of these only to such extent as it may find in them reasons for the decision it has to give in order to settle the sole dispute submitted to it, the subject of which has just been stated. [p 15]

***

The Temple of Preah Vihear is an ancient sanctuary and shrine situated on the borders of Thailand and Cambodia. Although now partially in ruins, this Temple has considerable artistic and archaeological interest, and is still used as a place of pilgrimage. It stands on a promontory of the same name, belonging to the eastern sector of the Dangrek range of mountains which, in a general way, constitutes the boundary between the two countries in this region— Cambodia to the south and Thailand to the north. Considerable portions of this range consist of a high cliff-like escarpment rising abruptly above the Cambodian plain. This is the situation at Preah Vihear itself, where the main Temple buildings stand in the apex of a triangular piece of high ground jutting out into the plain. From the edge of the escarpment, the general inclination of the ground in the northerly direction's downwards to the Nam Moun river, which is in Thailand.

It will be apparent from the description just given that a frontier line which ran along the edge of the escarpment, or which at any rate ran to the south and east of the Temple area, would leave this area in Thailand; whereas a line running to the north, or to the north and west, would place it in Cambodia.

Thailand has urged that the edge of this escarpment constitutes the natural and obvious line for a frontier in this region. In support of this view Thailand has referred to the documentary evidence indicative of the desire of the Parties to establish frontiers which would not only be "natural", but visible and unmistakable—such as rivers, mountain ranges, and hence escarpments, where they exist.

The desire of the Parties for a natural and visible frontier could have been met by almost any line which followed a recognizable course along the main chain of the Dangrek range. It could have been a crest line, a watershed line or an escarpment line (where an escarpment existed, which was far from always being the case). As will be seen presently, the Parties provided for a watershed line. In so doing, they must be presumed to have realized that such a line would not necessarily, in any particular locality, be the same line as the line of the crest or escarpment. They cannot therefore be presumed to have intended that, wherever an escarpment existed, the frontier must lie along it, irrespective of all other considerations.
The Parties have also relied on other arguments of a physical, historical, religious and archaeological character, but the Court is unable to regard them as legally decisive.

***

As concerns the burden of proof, it must be pointed out that though, from the formal standpoint, Cambodia is the plaintiff, [p 16] having instituted the proceedings, Thailand also is a claimant because of the claim which was presented by her in the second Submission of the Counter-Memorial and which relates to the sovereignty over the same piece of territory. Both Cambodia and Thailand base their respective claims on a series of facts and contentions which are asserted or put forward by one Party or the other. The burden of proof in respect of these will of course lie on the Party asserting or putting them forward.

***

Until Cambodia attained her independence in 1953 she was part of French Indo-China, and her foreign relations—like those of the rest of French Indo-China—were conducted by France as the protecting Power. It is common ground between the Parties that the present dispute has its fons et origo in the boundary settlements made in the period 1904-1908, between France and Siam (as Thailand was then called) and, in particular, that the sovereignty over Preah Vihear depends upon a boundary treaty dated 13 February 1904, and upon events subsequent to that date. The Court is therefore not called upon to go into the situation that existed between the Parties prior to the Treaty of 1904.

The relevant provisions of the Treaty of 13 February 1904, which regulated inter alia the frontier in the eastern Dangrek region, were as follows:

[Translation by the Registry]

"Article 1

The frontier between Siam and Cambodia starts, on the left shore of the Great Lake, from the mouth of the river Stung Roluos, it follows the parallel from that point in an easterly direction until it meets the river Prek Kompong Tiam, then, turning northwards, it merges with the meridian from that meeting-point as far as the Pnom Dang Rek mountain chain. From there it follows the watershed between the basins of the Nam Sen and the Mekong, on the one hand, and the Nam Moun, on the other hand, and joins the Pnom Padang chain the crest of which it follows eastwards as far as the Mekong. LTpstream from that point, the Mekong remains the frontier of the Kingdom of Siam, in accordance with Article 1 of the Treaty of 3 October 1893."

"Article 3

There shall be a delimitation of the frontiers between the Kingdom of Siam and the territories making up French Indo-China. This delimitation will be carried out by Mixed Commissions composed of officers appointed by the two contracting countries. The work will relate to the frontier determined by Articles 1 and 2, and the region lying between the Great Lake and the sea."

It will be seen, in the first place, that these articles make no mention of Preah Vihear as such. It is for this reason that the Court [p 17] can only give a decision as to the sovereignty over the Temple area after having examined what the frontier line is. Secondly, whereas the general character of the frontier established by Article i was, along the Dangrek range, to be a watershed line, the exact course of this frontier was, by virtue of Article 3, to be delimited by a Franco-Siamese Mixed Commission. It is to be observed, moreover, that what had to be delimited was "the frontiers" between Siam and French Indo-China; and although this delimitation had, prima facie, to be carried out by reference to the criterion indicated in Article 1, the purpose of it was to establish the actual line of the frontier. In consequence, the line of the frontier would, to all intents and purposes, be the line resulting from the work of delimitation, unless the delimitation were shown to be invalid.

***

In due course, a Mixed Commission composed of French and Siamese members was set up, charged with the task of delimiting the frontier in various districts, including the eastern sector of the Dangrek range in which Preah Vihear is situated. This Mixed Commission was composed of two sections, one French and one Siamese, sitting together—one consisting of French topographical and administrative officers under a French president, and the other of Siamese members under a Siamese president. So far as the frontier in the Dangrek range was concerned, the task of this Mixed Commission was confined to the eastern sector (roughly east of the Pass of Kel) in which Preah Vihear is situated. At this time the western sector of the Dangrek lay wholly in Thailand. It was only when a further boundary settlement, under a treaty dated 23 March 1907, brought within Cambodia various districts abutting on the western Dangrek sector, that the latter became a frontier region. The task of delimiting the frontier in this latter region was given to a second Mixed Commission set up under the 1907 Treaty.

The Mixed Commission set up under the Treaty of 1904 held its first meeting in January 1905, but did not reach that part of its operations that concerned the frontier along the eastern sector of the Dangrek range until December 1906, although it appears from the minutes of the Commission's meeting of 2 December 1906 that •one of the French members of the Commission, Captain Tixier, had passed along the Dangrek in February 1905. At the meeting of 2 December 1906, held at Angkor-Wat, it was agreed that the Commission should ascend the Dangrek from the Cambodian plain by the Pass of Kel, which lies westwards of Preah Vihear, and travel eastwards along the range by the same route (or along the same line) as had been reconnoitred by Captain Tixier in 1905 ("le tracé qu'a reconnu ... le capitaine Tixier"). It was stated that all the [p 18] necessary reconnaissance between this route and the crest line (to which it ran roughly parallel) could be carried out by this method, since the route was, at the most, only ten to fifteen kilometres from the crest, on the Siamese side. It has not been contested that the Presidents of the French and Siamese sections of the Commission, as representing it, duly made this journey, and that in the course of it they visited the Temple of Preah Vihear. But there is no record of any decision that they may have taken.

At this same meeting of 2 December 1906, it was also agreed that another of the members of the French section of the Commission, Captain Oum, should, starting at the eastern end, survey the whole of the eastern part of the Dangrek range, in which Preah Vihear is situated, and that he would leave for this purpose the next day.

It is thus clear that the Mixed Commission fully intended to delimit the frontier in this sector of the Dangrek and that it took all the necessary steps to put the work of delimitation in hand. The work must have been accomplished, for at the end of January 1907 the French Minister at Bangkok reported to the Minister of Foreign Affairs in Paris that he had been formally notified by the President of the French section of the Mixed Commission that the whole work of delimitation had been finished without incident, and that the frontier line had been definitely established, except in the region of Siem Reap. Furthermore, in a report on the whole work of delimitation, dated 20 February 1907, destined for his own Government, the President said that: "All along the Dangrek and as far as the Mekong, the fixing of the frontier could not have involved any difficulty." Mention may also be made of a map produced by Thailand, recently prepared by the Royal Thai Survey Department, Bangkok, tracing in the Dangrek the "Route followed by the Mixed Commission of 1904".

It seems clear therefore that a frontier was surveyed and fixed; but the question is what was that frontier (in particular in the region of Preah Vihear), by whom was it fixed, in what way, and upon whose instructions ? The difficultly in answering these questions lies in the fact that, after the minutes of the meeting of the First Commission on 2 December 1906, there is no further reference whatever, in any minutes of later meetings, to the question of the frontier in the Dangrek region.

It appears that at about this time the Commission had in substance finished its work on the ground and was awaiting the reports and provisional maps of the survey officers (Captain Oum and others). These reports and maps would not be available until February-March 1907 when, in normal circumstances, another meeting of the Commission would have been held to consider them. It appears that a meeting had been provisionally fixed for 8 March. [p 19]

That it was certainly the intention to call one, can be seen from a despatch from the French Minister in Bangkok to the Minister of Foreign Affairs in Paris, dated 23 February 1907, covering the report from Colonel Bernard, President of the French section of the Commission. The Minister, in his despatch, said: "The maps indicating the frontier can be brought up to date in a fairly short time and the plenary meeting of the French and Siamese Commissioners will probably be held before 15 March." No meeting apparently ever took place. In the meantime the two Governments had entered into negotiations for a further boundary treaty. This treaty was signed on 23 March 1907, and provided for exchanges of territory and a comprehensive regulation of all those frontiers not covered by the previous treaty settlement of 1904.

A second Mixed Commission of Delimitation was then set up under the Treaty of 1907. As already mentioned, part of its task was to delimit that sector of the Dangrek region not having come within the ambit of the First Commission, namely from the Pass of Kel westwards, and therefore not including Preah Vihear which lay to the east. There was in fact some overlapping of the work of the two Commissions in the Kel region, but this overlapping did not extend to Preah Vihear. There is, however, evidence in the records of the Second Commission that, at or near the Pass of Kel, the line drawn by this Commission joined up with an already existing line proceeding eastwards to the Temple area and beyond. There is no definite indication as to what this line was, or how it had come to be established; but the presumption that it was in some manner or other the outcome of the survey work which the First Commission had put in hand, and which the President of its French section, in his report of 20 February 1907, stated to have been accomplished without difficulty is, in the circumstances, overwhelmingly strong. The Court has noted that although, under Article IV of the Treaty of 1907, the task of the Second Mixed Commission was to delimit the "new frontiers" established by that Treaty, the Commission also had the task, under Clause III of the Protocol attached to the Treaty, of delimiting all that part of the frontier defined in Clause I of the Protocol. This latter provision related to the entire Dangrek range from a point in its western half to the eastern continuation of the Dangrek, the Pnom Padang range, as far as the River Mekong. Therefore, had the eastern Dangrek and Pnom Padang sectors not already been delimited by the first (1904) Mixed Commission, it would have been the duty of the second (1907) Commission to do this work. This Commission did not do it, apart from the overlap (not extending to Preah Vihear) already mentioned, and therefore the presumption must be that it had already been done. [p 20]

The First Mixed Commission apparently did not hold any formal meeting after 19 January 1907. It must not be forgotten that, at the time when such a meeting might have been held for the purpose of winding up the work of the Commission, attention in both countries, on the part of those who were specially qualified to act and speak on their behalf in these matters, was directed towards the conclusion of the Treaty of 23 March 1907. Their chief concern, particularly in the case of Colonel Bernard, could hardly have been the formal completion of the results of the delimitation they had carried out.

The final stage of the operation of delimitation was the preparation and publication of maps. For the execution of this technical work, the Siamese Government, which at that time did not dispose of adequate means, had officially requested that French topographical officers should map the frontier region. It is clear from the opening paragraph of the minutes of the meeting of the first Mixed Commission on 29 November 1905 that this request had the approval of the Siamese section of the Commission, which may indeed have inspired it, for in the letter of 20 August 1908 in which the Siamese Minister in Paris communicated to his Government the eventual results of this work of mapping, he referred to "the Mixed Commission of Delimitation of the frontiers and the Siamese Commissioners' request that the French Commissioners prepare maps of various frontiers". That this was the deliberate policy of the Siamese authorities is also shown by the fact that in the second (1907) Mixed Commission, the French members of the Commission were equally requested by their Siamese colleagues to carry out cartographical work, as can be seen from the minutes of the meeting of 6 June 1908.

The French Government duly arranged for the work to be done by a team of four French officers, three of whom, Captains Tixier, Kerler and de Batz, had been members of the first Mixed Commission. This team worked under the general direction of Colonel Bernard, and in the late autumn of 1907 it completed a series of eleven maps covering a large part of the frontiers between Siam and French Indo-China, including those portions that are material in the present case. The maps were printed and published by a well-known French cartographical firm, H. Barrere.

The eleven maps were in due course communicated to the Siamese Government, as being the maps requested by the latter, and the Court will consider later the circumstances of that communication and the deductions to be drawn from it. Three of the maps had been overtaken by events, inasmuch as the former frontier areas they showed had, by virtue of the Treaty of March 1907, now become situated wholly in Cambodia. Siam was not therefore called upon either to accept or reject them. Her interest in the other maps remained. Amongst these was one of that part of the Dangrek [p 21] range in which the Temple is situated, and on it was traced a frontier line purporting to be the outcome of the work of delimitation and showing the whole Preah Vihear promontory, with the Temple area, as being on the Cambodian side. If therefore the delimitation carried out in respect of the Eastern Dangrek sector established or was intended to establish a watershed line, this map purported to show such a line. This map was filed by Cambodia as Annex I to its Memorial, and has become known in the case (and will be referred to herein) as the Annex I map.

It is on this map that Cambodia principally relies in support of her claim to sovereignty over the Temple. Thailand, on the other hand, contests any claim based on this map, on the following grounds: first, that the map was not the work of the Mixed Commission, and had therefore no binding character; secondly, that at Preah Vihear the map embodied a material error, not explicable on the basis of any exercise of discretionary powers of adaptation which the Commission may have possessed. This error, according to Thailand's contention, was that the frontier line indicated on the map was not the true watershed line in this vicinity, and that a line drawn in accordance with the true watershed line would have placed, and would now place, the Temple area in Thailand. It is further contended by Thailand that she never accepted this map or the frontier line indicated on it, at any rate so far as Preah Vihear is concerned, in such a way as to become bound thereby; or, alternatively that, if she did accept the map, she did so only under, and because of, a mistaken belief (upon which she relied) that the map line was correctly drawn to correspond with the watershed line.

The Court will, for the moment, confine itself to the first of these contentions, based on an argument which the Court considers to be correct, namely that the map was never formally approved by the first Mixed Commission as such, since that Commission had ceased to function some months before the production of the map. The record does not show whether the map and the line were based on any decisions or instructions given by the Commission to the surveying officers while it was still functioning. What is certain is that the map must have had a basis of some sort, and the Court thinks there can be no reasonable doubt that it was based on the work of the surveying officers in the Dangrek sector. Being one of the series of maps of the frontier areas produced by French Government topographical experts in response to a request made by the Siamese authorities, printed and published by a Paris firm of repute, all of which was clear from the map itself, it was thus invested with an official standing; it had its own inherent technical authority; and its provenance was open and obvious. The Court must nevertheless conclude that, in its inception, and at the moment of its production, it had no binding character. [p 22]

***
Thailand has argued that in the absence of any delimitation approved and adopted by the Mixed Commission, or based on its instructions, the line of the frontier must necessarily—by virtue of Article 1 of the Treaty of 1904—follow strictly the line of the true watershed, and that this line, at Preah Vihear, would place the Temple in Thailand. While admitting that the Mixed Com-mission had a certain discretion to depart from the watershed line in order to avoid anomalies, and to take account of certain purely local considerations, Thailand contends that any departure such as to place Preah Vihear in Cambodia would have far exceeded the scope of any discretionary powers the Mixed Commission could have had authority to exercise without specific reference to the Governments.

Whatever substance these contentions may have, taken by themselves, the Court considers that they do not meet the real issues here involved. Even if there was no delimitation of the frontier in the eastern sector of the Dangrek approved and adopted by the Mixed Commission, it was obviously open to the Governments themselves to adopt a delimitation for that region, making use of the work of the technical members of the Mixed Commission. As regards any departures from the watershed line which any such delimitation embodied—since, according to Thailand's own contention, the delimitation indicated on the Annex I map was not the Mixed Commission's—there is no point in discussing whether such departures as may have occurred at Preah Vihear fell within the Commission's discretionary powers or not. The point is that it was certainly within the power of the Governments to adopt such departures.

The real question, therefore, which is the essential one in this case, is whether the Parties did adopt the Annex I map, and the line indicated on it, as representing the outcome of the work of delimitation of the frontier in the region of Preah Vihear, thereby conferring on it a binding character.

Thailand denies this so far as she is concerned, representing herself as having adopted a merely passive attitude in what ensued. She maintains also that a course of conduct, involving at most a failure to object, cannot suffice to render her a consenting party to a departure at Preah Vihear from the watershed line specified by Article 1 of the Treaty of 1904, so great as to affect the sovereignty over the Temple area.

The Court sees the matter differently. It is clear from the record that the publication and communication of the eleven maps referred [p 23] to earlier, including the Annex I map, was something of an occasion. This was no mere interchange between the French and Siamese Governments, though, even if it had been, it could have sufficed in law. On the contrary, the maps were given wide publicity in all technically interested quarters by being also communicated to the leading geographical societies in important countries, and to other circles regionally interested; to the Siamese legations accredited to the British, German, Russian and United States Governments; and to all the members of the Mixed Commission, French and Siamese. The full original distribution consisted of about one hundred and sixty sets of eleven maps each. Fifty sets of this distribution were allocated to the Siamese Government. That the Annex I map was communicated as purporting to represent the outcome of the work of delimitation is clear from the letter from the Siamese Minister in Paris to the Minister of Foreign Affairs in Bangkok, dated 20 August 1908, in which he said that "regarding the Mixed Commission of Delimitation of the frontiers and the Siamese Commissioners' request that the French Commissioners prepare maps of various frontiers, the French Commissioners have now finished their work". He added that a series of maps had been brought to him in order that he might forward them to the Siamese Minister of Foreign Affairs. He went on to give a list of the eleven maps, including the map of the Dangrek region—fifty sheets of each. He ended by saying that he was keeping two sheets of each map for his Legation and was sending one sheet of each to the Legations in London, Berlin, Russia and the United States of America.

It has been contended on behalf of Thailand that this communication of the maps by the French authorities was, so to speak, ex parte, and that no formal acknowledgment of it was either requested of, or given by, Thailand. In fact, as will be seen presently, an acknowledgment by conduct was undoubtedly made in a very definite way; but even if it were otherwise, it is clear that the circumstances were such as called for some reaction, within a reasonable period, on the part of the Siamese authorities, if they wished to disagree with the map or had any serious question to raise in regard to it. They did not do so, either then or for many years, and thereby must be held to have acquiesced. Qui tacet consentire videtur si loqui debuisset ac potuisset.

So far as the Annex I map is concerned, it was not merely the circumstances of the communication of this and the other maps that called for some reaction from the Siamese side, if reaction there was to be; there were also indications on the face of the map sheet which required a reaction if the Siamese authorities had any reason to contend that the map did not represent the outcome of [p 24] the work of delimitation. The map—together with the other maps— was, as already stated, communicated to the Siamese members of the Mixed Commission. These must necessarily have known (and through them the Siamese Government must have known) that this map could not have represented anything formally adopted by the Mixed Commission, and therefore they could not possibly have been deceived by the title of the map, namely, "Dangrek— Commission of Delimitation between Indo-China and Siam" into supposing that it was purporting to be a production of the Mixed Commission as such. Alternatively, if the Siamese members of the Commission did suppose otherwise, this could only have been because, though without recording them, the Mixed Commission had in fact taken some decisions on which the map was based; and of any such decisions the Siamese members of the Commission would of course have been aware.

The Siamese members of the Commission must also have seen the notice appearing in the top left-hand corner of the map sheet to the effect that the work on the ground had been carried out by Captains Kerler and Oum. They would have known, since they were present at the meeting of the Commission held on 2 December 1906, that Captain Oum had then been instructed to carry out the survey of the eastern sector of the Dangrek range, covering Preah Vihear, and that he was to leave the next day to take up this assignment. They said nothing—either then or later—to suggest that the map did not represent the outcome of the work of delimitation or that it was in any way inaccurate.

That the Siamese authorities by their conduct acknowledged the receipt, and recognized the character, of these maps, and what they purported to represent, is shown by the action of the Minister of the Interior, Prince Damrong, in thanking the French Minister in Bangkok for the maps, and in asking him for another fifteen copies of each of them for transmission to the Siamese provincial Governors.
Further evidence is afforded by the proceedings of the subsequent Commission of Transcription which met in Bangkok in March of the following year, 1909, and for some months thereafter. This was a mixed Franco-Siamese Commission set up by the Parties with the object of getting an official Siamese geographical service started, through a consolidation of all the work of the two Mixed Commissions of 1904 and 1907. A primary aim was to convert the existing maps into handy atlas form, and to give the French and Siamese terms used in them their proper equivalents in the other languages. No suggestion that the Annex I map or line was unacceptable was made in the course of the work of this Commission. [p 25]

***
It was claimed on behalf of Thailand that the maps received from Paris were only seen by minor officials who had no expertise in cartography, and would know nothing about the Temple of Preah Vihear. Indeed it was suggested during the oral proceedings that no one in Siam at that time knew anything about the Temple or would be troubling about it.

The Court cannot accept these contentions either on the facts or the law. If the Siamese authorities did show these maps only to minor officials, they clearly acted at their own risk, and the claim of Thailand could not, on the international plane, derive any assistance from that fact. But the history of the matter, as set out above, shows clearly that the maps were seen by such persons as Prince Devawongse, the Foreign Minister, Prince Damrong, the Minister of the Interior, the Siamese members of the First Mixed Commission, the Siamese members of the Commission of Transcription ; and it must also be assumed that the Annex I map was seen by the Governor of Khukhan province, the Siamese province adjoining the Preah Vihear region on the northern side, who must have been amongst those for whom extra copies were requested by Prince Damrong. None of these persons was a minor official. All or most had local knowledge. Some must have had knowledge of the Dangrek region. It is clear from the documentation in the case that Prince Damrong took a keen personal interest in the work of delimitation, and had a profound knowledge of archaeological monuments. It is not conceivable that the Governor of Khukhan province, of which Preah Vihear formed part up to the 1904 settlement, was ignorant of its existence.

In any case this particular contention of Thailand's is decisively disproved by a document deposited by Thailand herself, according to which the Temple was in 1899 "re-discovered" by the Siamese Prince Sanphasit, accompanied by some fifteen to twenty officials and local dignitaries, including, it seems, the then Governor and Deputy-Governor of Khukhan. It thus appears that only nine years previous to the receipt of the Annex I map by the Siamese authorities, a considerable number of persons having high official standing in Siam knew of Preah Vihear.

The Court moreover considers that there is no legal foundation for the consequence it is attempted to deduce from the fact that no one in Thailand at that time may have known of the importance of the Temple or have been troubling about it. Frontier rectifications cannot in law be claimed on the ground that a frontier area has turned out to have an importance not known or suspected when the frontier was established. [p 26]

***

It follows from the preceding findings that the Siamese authorities in due course received the Annex I map and that they accepted it. Now, however, it is contended on behalf of Thailand, so far as the disputed area of Preah Vihear is concerned, that an error was committed, an error of which the Siamese authorities were unaware at the time when they accepted the map.

It is an established rule of law that the plea of error cannot be allowed as an element vitiating consent if the party advancing it contributed by its own conduct to the error, or could have avoided it, or if the circumstances were such as to put that party on notice of a possible error. The Court considers that the character and qualifications of the persons who saw the Annex I map on the Siamese side would alone make it difficult for Thailand to plead error in law. These persons included the members of the very Commission of Delimitation within whose competence this sector of the frontier had lain. But even apart from this, the Court thinks that there were other circumstances relating to the Annex I map which make the plea of error difficult to receive.

An inspection indicates that the map itself drew such pointed attention to the Preah Vihear region that no interested person, nor anyone charged with the duty of scrutinizing it, could have failed to see what the map was purporting to do in respect of that region. If, as Thailand has argued, the geographical configuration of the place is such as to make it obvious to anyone who has been there that the watershed must lie along the line of the escarpment (a fact which, if true, must have been no less evident in 1908), then the map made it quite plain that the Annex I line did not follow the escarpment in this region since it was plainly drawn appreciably to the north of the whole Preah Vihear promontory. Nobody looking at the map could be under any misapprehension about that.

Next, the map marked Preah Vihear itself quite clearly as lying on the Cambodian side of the line, using for the Temple a symbol which seems to indicate a rough plan of the building and its stairways.

It would thus seem that, to anyone who considered that the line of the watershed at Preah Vihear ought to follow the line of the escarpment, or whose duty it was to scrutinize the map, there was everything in the Annex I map to put him upon enquiry. Furthermore, as has already been pointed out, the Siamese Government knew or must be presumed to have known, through the Siamese members of the Mixed Commission, that the Annex I map had never been formally adopted by the Commission. The Siamese authorities knew it was the work of French topographical officers to whom they had themselves entrusted the work of producing the [p 27]
maps. They accepted it without any independent investigation, and cannot therefore now plead any error vitiating the reality of their consent. The Court concludes therefore that the plea of error has not been made out.

***
The Court will now consider the events subsequent to the period 1904-1909.

The Siamese authorities did not raise any query about the Annex I map as between themselves and France or Cambodia, or expressly repudiate it as such, until the 1958 negotiations in Bangkok, when, inter alia, the question of Preah Vihear came under discussion between
Thailand and Cambodia. Nor was any question raised even after 1934-1935, when Thailand carried out a survey of her own in this region, and this survey had, in Thailand's view, established a divergence between the map line and the true line of the watershed—a divergence having the effect of placing the Temple in Cambodia. Although, after this date, Thailand eventually pro-duced some maps of her own showing Preah Vihear as being in Thailand, she continued, even for public and official purposes, to use the Annex I map, or other maps showing Preah Vihear as lying in Cambodia, without raising any query about the matter (her explanations as to this will be considered presently). Moreover, the Court finds it difficult to overlook such a fact as, for instance, that in 1937, even after Thailand's own survey in 1934-1935, and in the same year as the conclusion of a treaty with France in which, as will be seen, the established common frontiers were reaffirmed, the Siamese Royal Survey Department produced a map showing Preah Vihear as lying in Cambodia.

Thailand had several opportunities of raising with the French authorities the question of the Annex I map. There were first of all the negotiations for the 1925 and 1937 Treaties of Friendship, Commerce and Navigation between France, on behalf of Indo-China, and Siam. These Treaties, although they provided for a general process of revision or replacement of previous Agreements, excluded from this process the existing frontiers as they had been established under the Boundary Settlements of 1893, 1904 and 1907. Thereby, and in certain more positive provisions, the Parties confirmed the existing frontiers, whatever they were. These were occasions (particularly in regard to the negotiations for the 1937 Treaty, which occurred only two years after Thailand's own survey of the frontier regions had disclosed, in her belief, a serious divergence between the map line and the watershed line at Preah Vihear) on which it would have been natural for Thailand to raise the matter, if she considered the map indicating the frontier at Preah Vihear to be [p 28] incorrect—occasions on which she could and should have done so if that was her belief. She did not do so and she even, as has been seen, produced a map of her own in 1937 showing Preah Vihear as being in Cambodia. That this map may have been intended for internal military use does not seem to the Court to make it any less evidence of Thailand's state of mind. The inference must be—particularly in regard to the 1937 occasion—that she accepted or still accepted the Annex I map, and the line it indicated, even if she believed it incorrect, even if, after her own survey of 19341935, she thought she knew it was incorrect.

Thailand having temporarily come into possession of certain parts of Cambodia, including Preah Vihear, in 1941, the Ministry of Information of Thailand published a work entitled "Thailand during national reconstruction" in which it was stated in relation to Preah Vihear that it had now been "retaken" for Thailand. This has been represented by Thailand as being an error on the part of a minor official. Nevertheless, similar language, suggesting that Thailand had been in possession of Preah Vihear only since about 1940, was used by representatives of Thailand in the territorial negotiations that took place between Thailand and Cambodia at Bangkok in 1958.

After the war, by a Settlement Agreement of November 1946 with France, Thailand accepted a. reversion to the status quo ante 1941. It is Thailand's contention that this reversion to the status quo did not affect Preah Vihear because Thailand already had sovereignty over it before the war. The Court need not discuss this contention, for whether Thailand did have such sovereignty is precisely what is in issue in these proceedings. The important point is that, in consequence of the war events, France agreed to set up a Franco-Siamese Conciliation Commission consisting of the two representatives of the Parties and three neutral Commissioners, whose terms of reference were specifically to go into, and make recommendations on an equitable basis in regard to, any complaints or proposals for revision which Thailand might wish to make as to, inter alia, the frontier settlements of 1904 and 1907. The Commission met in 1947 in Washington, and here therefore was an outstanding opportunity for Thailand to claim a rectification of the frontier at Preah Vihear on the ground that the delimitation embodied a serious error which would have caused Thailand to reject it had she known of the error in 1908-1909. In fact, although Thailand made complaints about the frontier line in a considerable number of regions, she made none about Preah Vihear. She even (12 May 1947) filed with the Commission a map showing Preah Vihear as lying in Cambodia. Thailand contends that this involved no adverse implications as regards her claim to the Temple, because [p 29] the Temple area was not in issue before the Commission, that it was other regions that were under discussion, and that it was in relation to these that the map was used. But it is precisely the fact that Thailand had raised these other questions, but not that of Preah Vihear, which requires explanation; for, everything else apart, Thailand was by this time well aware, from certain local happenings in relation to the Temple, to be mentioned presently, that France regarded Preah Vihear as being in Cambodian territory—even if this had not already and long since been obvious from the frontier line itself, as mapped by the French authorities and communicated to the Siamese Government in 1908. The natural inference from Thailand's failure to mention Preah Vihear on this occasion is, again, that she did not do so because she accepted the frontier at this point as it was drawn on the map, irrespective of its correspondence with the watershed line.

As regards the use of a map showing Preah Vihear as lying in Cambodia, Thailand maintains that this was for purely cartographical reasons, that there were no other maps, or none that were so convenient, or none of the right scale for the occasion. The Court does not find this explanation convincing. Thailand could have used the map but could also have entered some kind of reservation with France as to its correctness. This she did not do.

As regards her failure even to raise the question of the map as such until 1958, Thailand states that this was because she was, at all material times, in possession of Preah Vihear; therefore she had no need to raise the matter. She indeed instances her acts on the ground as evidence that she never accepted the Annex I line at Preah Vihear at all, and contends that if she never accepted it she clearly had no need to repudiate it, and that no adverse conclusions can be drawn from her failure to do so. The acceptability of this explanation must obviously depend on whether in fact it is the case that Thailand's conduct on the ground affords ex post facto evidence sufficient to show that she never accepted the Annex I line in 1908 in respect of Preah Vihear, and considered herself at all material times to have the sovereignty over the Temple area.

***

The Court has considered the evidence furnished by Thailand of acts of an administrative character performed by her officials at or relative to Preah Vihear. France, and subsequently Cambodia, [p 30] in view of her title founded on the Treaty of 1904, performed only a very few routine acts of administration in this small, deserted area. It was specifically admitted by Thailand in the course of the oral hearing that if Cambodia acquired sovereignty over the Temple area by virtue of the frontier settlement of 1904, she did not subsequently abandon it, nor did Thailand subsequently obtain it by any process of acquisitive prescription. Thailand's acts on the ground were therefore put forward as evidence of conduct as sovereign, sufficient to negative any suggestion that, under the 1904 Treaty settlement, Thailand accepted a delimitation having the effect of attributing the sovereignty over Preah Vihear to Cambodia. It is therefore from this standpoint that the Court must consider and evaluate these acts. The real question is whether they sufficed to efface or cancel out the clear impression of acceptance of the frontier line at Preah Vihear to be derived from the various considerations already discussed.

With one or two important exceptions to be mentioned presently, the acts concerned were exclusively the acts of local, provincial, authorities. To the extent that these activities took place, it is not clear that they had reference to the summit of Mount Preah Vihear and the Temple area itself, rather than to places somewhere in the vicinity. But however that may be, the Court finds it difficult to regard such local acts as overriding and negativing the consistent and undeviating attitude of the central Siamese authorities to the frontier line as mapped.

In this connection, much the most significant episode consisted of the visit paid to the Temple in 1930 by Prince Damrong, formerly Minister of the Interior, and at this time President of the Royal Institute of Siam, charged with duties in connection with the National Library and with archaeological monuments. The visit was part of an archaeological tour made by the Prince with the permission of the King of Siam, and it clearly had a quasi-official character. When the Prince arrived at Preah Vihear, he was officially received there by the French Resident for the adjoining Cambodian province, on behalf of the Resident Superior, with the French flag flying. The Prince could not possibly have failed to see the implications of a reception of this character. A clearer affirmation of title on the French Indo-Chinese side can scarcely be imagined. It demanded a reaction. Thailand did nothing. Furthermore, when Prince Damrong on his return to Bangkok sent the French Resident some photographs of the occasion, he used language which seems to admit that France, through her Resident, had acted as the host country.

The explanations regarding Prince Damrong's visit given on behalf of Thailand have not been found convincing by the Court. Looking at the incident as a whole, it appears to have amounted [p 31] to a tacit recognition by Siam of the sovereignty of Cambodia (under French Protectorate) over Preah Vihear, through a failure to react in any way, on an occasion that called for a reaction in order to affirm or preserve title in the face of an obvious rival claim. What seems clear is that either Siam did not in fact believe she had any title—and this would be wholly consistent with her attitude all along, and thereafter, to the Annex I map and line—or else she decided not to assert it, which again means that she accepted the French claim, or accepted the frontier at Preah Vihear as it was drawn on the map.


***

The remaining relevant facts -must now be stated. In February 1949, not long after the conclusion of the proceedings of the Franco-Siamese Conciliation Commission, in the course of which, as has been seen, Thailand did not raise the question of Preah Vihear, France addressed a Note to the Government of Thailand stating that a report had been received of the stationing of four Siamese keepers at the Temple, and asking for information. There was no reply to this Note, nor to a follow-up Note of March 1949. In May 1949, France sent a further Note, setting out briefly, but quite explicitly, the grounds on which she considered Preah Vihear to be in Cambodia, and pointing out that a map produced by Thailand herself had recognized this fact. The withdrawal of the keepers was requested. Although there was an error in this Note, the significance of the latter was that it contained an unequivocal assertion of sovereignty. This French Note also received no reply. In July 1950, a further Note was sent. This too remained unanswered.

In these circumstances Cambodia, on attaining her independence in 1953, proposed, for her part, to send keepers or guards to the Temple, in the assertion or maintenance of her position. However, finding that Thai keepers were already there, the Cambodian keepers withdrew, and Cambodia sent a Note dated January 1954 to the Government of Thailand asking for information. This received a mere acknowledgment, but no explanation. Nor was there, even then, any formal affirmation of Thailand's claim. At the end of March 1954, the Government of Cambodia, drawing attention to the fact that no substantive reply to its previous Note had been received, notified the Government of Thailand that it now proposed to replace the previously withdrawn Cambodian keepers or guards by some Cambodian troops. In this Note Cambodia specifically referred to the justification of the Cambodian claim contained in the French Note of May 1949. This Cambodian Note also was not [p 32] answered. However, the Cambodian troops were not in fact sent; and in June 1954, Cambodia addressed to Thailand a further Note stating that, as information had been received to the effect that Thai troops were already in occupation, the despatch of the Cambodian troops had been suspended in order not to aggravate the situation. The Note went on to ask that Thailand should either withdraw her troops or furnish Cambodia with her views on the matter. This Note equally received no reply. But the Thai "troops" (the Court understands that they are in fact a police force) remained. Again, therefore, it would seem that Thailand, while taking certain local action, was not prepared to deny the French and Cambodian claim at the diplomatic level.

No further diplomatic correspondence was produced to the Court ; but eventually, in 1958, a conference was held at Bangkok between Thailand and Cambodia, to discuss various territorial matters in dispute between the Parties, including that of Preah Vihear. The representative of Thailand having declined to discuss the legal aspects of the matter, the negotiations broke down and Cambodia instituted the present proceedings.

***

The Court will now state the conclusions it draws from the facts as above set out.

Even if there were any doubt as to Siam's acceptance of the map in 1908, and hence of the frontier indicated thereon, the Court would consider, in the light of the subsequent course of events, that Thailand is now precluded by her conduct from asserting that she did not accept it. She has, for fifty years, enjoyed such benefits as the Treaty of 1904 conferred on her, if only the benefit of a stable frontier. France, and through her Cambodia, relied on Thailand's acceptance of the map. Since neither side can plead error, it is immaterial whether or not this reliance was based on a belief that the map was correct. It is not now open to Thailand, while continuing to claim and enjoy the benefits of the settlement, to deny that she was ever a consenting party to it.

The Court however considers that Thailand in 1908-1909 did accept the Annex I map as representing the outcome of the work of delimitation, and hence recognized the line on that map as being the frontier line, the effect of which is to situate Preah Vihear in Cambodian territory. The Court considers further that, looked at [p 33] as a whole, Thailand's subsequent conduct confirms and bears out her original acceptance, and that Thailand's acts on the ground do not suffice to negative this. Both Parties, by their conduct, recognized the line and thereby in effect agreed to regard it as being the frontier line.


***

The Court must now consider two further matters. Thailand contends that since 1908, and at any rate up to her own 1934-1935 survey, she believed that the map line and watershed line coincided, and therefore that if she accepted the map line, she did so only in that belief. It is evident that such a contention would be quite inconsistent with Thailand's equally strongly advanced contention that these acts in the concrete exercise of sovereignty evidenced her belief that she had sovereignty over the Temple area: for if Thailand was truly under a misapprehension about the Annex I line—if she really believed it indicated the correct watershed line— then she must have believed that, on the. basis of the map and her acceptance of it, the Temple area lay rightfully in Cambodia. If she had such a belief—and such a belief is implicit in any plea that she had accepted the Annex I map only because she thought it was correct—then her acts on the ground would have to be regarded as deliberate violations of the sovereignty which (on the basis of the assumptions above stated) she must be presumed to have thought Cambodia to possess. The conclusion is that Thailand cannot allege that she was under any misapprehension in accepting the Annex I line, for this is wholly inconsistent with the reason she gives for her acts on the ground, namely that she believedher self to possess sovereignty in this area.

It may be added that even if Thailand's plea of misapprehension could, in principle, be accepted, it should have been advanced shortly after Thailand's own survey of the disputed region was carried out in 1934-1935. Since then Thailand could not have been 'under any misapprehension.

***
There is finally one further aspect of the case with which the Court feels it necessary to deal. The Court considers that the acceptance of the Annex I map by the Parties caused the map to enter the treaty settlement and to become an integral part of it. It cannot be said that this process involved a departure from, and [p 34] even a violation of, the terms of the Treaty of 1904, wherever the map line diverged from the line of the watershed, for, as the Court sees the matter, the map (whether in all respects accurate by reference to the true watershed line or not) was accepted by the Parties in 1908 and thereafter as constituting the result of the interpretation given by the two Governments to the delimitation which the Treaty itself required. In other words, the Parties at that time adopted an interpretation of the treaty settlement which caused the map line, in so far as it may have departed from the line of the watershed, to prevail over the relevant clause of the treaty. Even if, however, the Court were called upon to deal with the matter now as one solely of ordinary treaty interpretation, it considers that the interpretation to be given would be the same, for the following reasons.

In general, when two countries establish a frontier between them, one of the primary objects is to achieve stability and finality. This is impossible if the line so established can, at any moment, and on the basis of a continuously available process, be called in question, and its rectification claimed, whenever any inaccuracy by reference to a clause in the parent treaty is discovered. Such a process could continue indefinitely, and finality would never be reached so long as possible errors still remained to be discovered. Such a frontier, so far from being stable, would be completely precarious. It must be asked why the Parties in this case provided for a delimitation, instead of relying on the Treaty clause indicating that the frontier line in this region would be the watershed. There are boundary treaties which do no more than refer to a watershed line, or to a crest line, and which make no provision for any delimitation in addition. The Parties in the present case must have had a reason for taking this further step. This could only have been because they regarded a watershed indication as insufficient by itself to achieve certainty and finality. It is precisely to achieve this that delimitations and map lines are resorted to.

Various factors support the view that the primary object of the Parties in the frontier settlements of 1904-1908 was to achieve certainty and finality. From the evidence furnished to the Court, and from the statements of the Parties themselves, it is clear that the whole question of Siam's very long frontiers with French IndoChina had, in the period prior to 1904, been a cause of uncertainty, trouble and friction, engendering what was described in one contemporary document placed before the Court as a state of "growing tension" in the relations between Siam and France. The Court thinks it legitimate to conclude that an important, not to say a [p 35] paramount object of the settlements of the 1904-1908 period (which brought about a comprehensive regulation of all outstanding frontier questions between the two countries), was to put an end to this state of tension and to achieve frontier stability on a basis of certainty and finality.

In the Franco-Siamese Boundary Treaty of 23 March 1907, the Parties recited in the preamble that they were desirous "of ensuring the final regulation of all questions relating to the common frontiers of Indo-China and Siam". A further token of the same object is to be found in the desire, of which the documentation contains ample evidence, and which was evinced by both Parties, for natural and visible frontiers. Even if, as the Court stated earlier, this is not in itself a reason for holding that the frontier must follow a natural and visible line, it does support the view that the Parties wanted certainty and finality by means of natural and visible lines.

The same view is strongly supported by the Parties' attitude over frontiers in the 1925 and 1937 Treaties. By specifically excluding frontiers from the process of revision of previous treaties, which the 1925 and 1937 Treaties otherwise effected, the Parties bore witness to the paramount importance they attached to finality in this field. Their attitude in 1925 and 1937 can properly be taken as evidence that they equally desired finality in the 1904-1908 period.

The indication of the line of the watershed in Article 1 of the 1904 Treaty was itself no more than an obvious and convenient way of describing a frontier line objectively, though in general terms. There is, however, no reason to think that the Parties attached any special importance to the line of the watershed as such, as compared with the overriding importance, in the interests of finality, of adhering to the map line as eventually delimited and as accepted by them. The Court, therefore, feels bound, as a matter of treaty interpretation, to pronounce in favour of the line as mapped in the disputed area.

***
Given the grounds on which the Court bases its decision, it becomes unnecessary to consider whether, at Preah Vihear, the line as mapped does in fact correspond to the true watershed line in this vicinity, or did so correspond in 1904-1908, or, if not, how the watershed line in fact runs. [p 36]
33

***

Referring finally to the Submissions presented at the end of the oral proceedings, the Court, for the reasons indicated at the beginning of the present Judgment, finds that Cambodia's first and second Submissions, calling for pronouncements on the legal status of the Annex I map and on the frontier line in the disputed region, can be entertained only to the extent that they give expression to grounds, and not as claims to be dealt with in the operative provisions of the Judgment. It finds on the other hand that Thailand, after having stated her own claim concerning sovereignty over Preah Vihear, confined herself in her Submissions at the end of the oral proceedings to arguments and denials opposing the contentions of the other Party, leaving it to the Court to word as it sees fit the reasons on which its Judgment is based.

In the presence of the claims submitted to the Court by Cambodia and Thailand, respectively, concerning the sovereignty over Preah Vihear thus in dispute between these two States, the Court finds in favour of Cambodia in accordance with her third Submission. It also finds in favour of Cambodia as regards the fourth Submission concerning the withdrawal of the detachments of armed forces.

As regards the fifth Submission of Cambodia concerning restitution, the Court considers that the request made in it does not represent any extension of Cambodia's original claim (in which case it would have been irreceivable at the stage at which it was first advanced). Rather is it, like the fourth Submission, implicit in, and consequential on, the claim of sovereignty itself. On the other hand, no concrete evidence has been placed before the Court showing in any positive way that objects of the kind mentioned in this Submission have in fact been removed by Thailand from the Temple or Temple area since Thailand's occupation of it in 1954. It is true that Thailand has not so much denied the allegation as contended that it is irreceivable. In the circumstances, however, the question of restitution is one on which the Court can only give a finding of principle in favour of Cambodia, without relating it to any particular objects.

For these reasons,

The Court,
by nine votes to three,

finds that the Temple of Preah Vihear is situated in territory under the sovereignty of Cambodia;
[p 37]

finds in consequence,

by nine votes to three,

that Thailand is under an obligation to withdraw any military or police forces, or other guards or keepers, stationed by her at the Temple, or in its vicinity on Cambodian territory;

by seven votes to five,

that Thailand is under an obligation to restore to Cambodia any objects of the kind specified in Cambodia's fifth Submission which may, since the date of the occupation of the Temple by Thailand in 1954, have been removed from the Temple or the Temple area by the Thai authorities.

Done in English and in French, the English text being authoritative, at the Peace Palace, The Hague, this fifteenth day of June, one thousand nine hundred and sixty-two, in three copies, one of which will be placed in the archives of the Court and the others transmitted to the Government of the Kingdom of Cambodia and to the Government of the Kingdom of Thailand, respectively.

(Signed) B. Winiarski,
President.

(Signed) Garnier-Coignet,
Registrar.

Judge Taxaka and Judge Morelli make the following Joint Declaration:

We wish to make clear the reason why, to our great regret, we were unable to concur in the majority opinion on the clause of the operative provisions of the Judgment concerning the restoration by Thailand to Cambodia of any objects which may have been removed from the Temple.

The fact that we voted against this clause of the operative provisions is in no way connected with the foundation of Cambodia's claim for the restoration of the objects in question. We did so because we think that the Court should have refrained from pronouncing on that claim since, having been made for the first time in the Submissions filed by Cambodia on 5 March 1962, it must be considered to be out of time. [p 38]

The claim as it is formulated in Cambodia's Application is directed not to the return of the Temple as such, but rather to sovereignty over the portion of territory in which the Temple is situated. It is directed, further, to one of the consequences flowing from Cambodian sovereignty over the said portion of territory, that is to say, Thailand's obligation to withdraw the detachments of armed forces it had stationed there, this consequence being explicitly indicated by Cambodia in its Application.

The other possible consequence of Cambodian sovereignty over the portion of territory in which the Temple is situated, namely, Thailand's obligation to restore to Cambodia any objects that may have been removed from the Temple, is a consequence that is not indicated in the Application. A claim for the return of the said objects cannot be considered to be implicitly contained in the claim presented by Cambodia in its Application, that claim having, as has been stated above, a completely different subject.

It is only if the claim by Cambodia had had directly as its subject the return of the Temple that it would have been possible, but then only through a liberal construction of such a claim, to consider that that claim was concerned also with objects which, having formed part of the Temple prior to the Application, had, also prior to the Application, been removed from the Temple.

Vice-President Alfaro and Judge Sir Gerald Fitzmaurice append to the Judgment of the Court statements of their Separate Opinions.

Judges Moreno Quintana, Wellington Koo and Sir Percy Spender append to the Judgment of the Court statements of their Dissenting Opinions.

(Initialled) B. W.
(Initialled) G.-C.
.

[p 39]
SEPARATE OPINION OF VICE-PRESIDENT ALFARO

The decision rendered by the Court in the present case sets forth considerations of law and fact in which I fully concur, especially for the reason that its essential basis is a principle of law to which I attribute great weight and which has been frequently applied by international tribunals, both of justice and arbitration.

This principle, as I understand it, is that a State party to an international litigation is bound .by its previous acts or attitude when they are in contradiction with its claims in the litigation.

I have no doubt that enunciated in these broad terms, the soundness and justice of the rule is generally accepted. However, it is manifest that wide divergences exist as to its meaning, its character, its scope and even its denomination; and inasmuch as a judgment of the Court could not be expected to deal with these particulars, I have thought necessary, as a matter of conscience, to state the views by which I have been guided in the adoption of this decision.

The principle, not infrequently called a doctrine, has been referred to by the terms of "estoppel", "preclusion", "forclusion", "acquiescence". I abstain from adopting any of these particular designations, as I do not believe that any of them fits exactly to the principle or doctrine as applied in international cases.

Spanish jurists, showing an objective critérium, call it "doctrina de los actos propios".

Judge Basdevant has given a definition of estoppel in his "Dictionnaire de la terminologie du droit international" which is doubtless very accurate. Here it is:

"Terme de procédure emprunté à la langue anglaise qui désigne l'objection péremptoire qui s'oppose à ce qu'une partie à un procès prenne une position qui contredit soit ce qu'elle a antérieurement admis expressément ou tacitement, soit ce qu'elle prétend soutenir dans la même instance."

However, when compared with definitions and comments contained in Anglo-American legal texts we cannot fail to recognize that while the principle, as above enunciated, underlies the Anglo-Saxon doctrine of estoppel, there is a very substantial difference between the simple and clear-cut rule adopted and applied in the international field and the complicated classifications, modalities, species, sub-species and procedural features of the municipal system. It thus results that in some international cases the decision may have nothing in common with the Anglo-Saxon estoppel, while [p 40] at the same time notions may be found in the latter that are manifestly extraneous to international practice and jurisprudence.

Of course, I feel bound to mention these designations since they have been so generally used in international texts, but I set them aside in stating my views with regard to the principle which is the subject of this separate opinion.

Whatever term or terms be employed to designate this principle such as it has been applied in the international sphere, its substance is always the same: inconsistency between claims or allegations put forward by a State, and its previous conduct in connection therewith, is not admissible (allegans contraria non au-diendus est). Its purpose is always the same: a State must not be permitted to benefit by its own inconsistency to the prejudice of another State (nemo potest mutare consilium suum in alterius in-juriam). A fortiori, the State must not be allowed to benefit by its inconsistency when it is through its own wrong or illegal act that the other party has been deprived of its right or prevented from exercising it. (Nullus commodum capere de sua injuria propria.) Finally, the legal effect of the principle is always the same: the party which by its recognition, its representation, its declaration, its conduct or its silence has maintained an attitude manifestly contrary to the right it is claiming before an international tribunal is precluded from claiming that right (venire contra factum proprium non valet).

The acts or attitude of a State previous to and in relation with rights in dispute with another State may take the form of an express written agreement, declaration, representation or recognition, or else that of a conduct which implies consent to or agreement with a determined factual or juridical situation.

A State may also be bound by a passive or negative attitude in respect of rights asserted by another State, which the former State later on claims to have. Passiveness in front of given facts is the most general form of acquiescence or tacit consent. Failure of a State to assert its right when that right is openly challenged by another State can only mean abandonment to that right. Silence by a State in the presence of facts contrary or prejudicial to rights later on claimed by it before an international tribunal can only be interpreted as tacit recognition given prior to the litigation. This interpretation obtains especially in the case of a contractual relationship directly and exclusively affecting two States. Failure to protest in circumstances when protest is necessary according to the general practice of States in order to assert, to preserve or to safeguard a right does likewise signify acquiescence or tacit recognition: the State concerned must be held barred from claiming before the international tribunal the rights it failed to assert or to preserve when they were openly challenged by word or deed. [p 41]

"The absence of protest"—says Lauterpacht—"may, in addition, in itself become a source of legal right inasmuch as it is related to— or forms a constituent element of—estoppel or prescription. Like these two generally recognized legal principles, the far-reaching effect of the failure to protest is not a mere artificiality of the law. It is an essential requirement of stability—a requirement even more important in the international than in other spheres; it is a precept of fair dealing inasmuch as it prevents states from playing fast and loose with situations affecting others; and it is in accordance with equity inasmuch as it protects a State from the contigency of incurring responsibilities and expense, in reliance on the apparent acquiescence of others, and being subsequently confronted with a challenge on the part of those very States." (Sovereignty over submarine areas in British Year Book 1950.)

The reasoning used and the jurisprudence developed as regards the subject of failure to protest is also applicable in the case of failure to reserve rights of which a State is legally possessed and which it is entitled to claim or exercise in due course. Such failure may be and has been interpreted as a waiver of such rights.

The principle that condemns contradiction between previous acts and subsequent claims is not to be regarded as a mere rule of evidence or procedure. The substantive character of the rule finds support in the writtings of several authors. As stated by Sir Frederick Pollock:

"estoppel is often described as a rule of evidence, as indeed it may be so described. But the whole concept is more correctly viewed as a substantive rule of law."

In the Nottebohm case the Liechtenstein Memorial stated that:

"It may be noted in this connection that the doctrine of estoppel, which is similar both in international and municipal law, is not, notwithstanding its apparent technical connotation, a formal and artificial rule of law. It is essentially grounded in considerations of good faith and honest conduct in the relations of States and individuals alike."

In my judgment, the principle is substantive in character. It constitutes a presumption juris et de jure in virtue of which a State is held to have abandoned its right if it ever had it, or else that such a State never felt that it had a clear legal title on which it. could base opposition to the right asserted or claimed by another State. In short, the legal effects of the principle are so fundamental that they decide by themselves alone the matter in dispute and its [p 42] infraction cannot be looked upon as a mere incident of the proceedings.

The primary foundation of this principle is the good faith that must prevail in international relations, inasmuch as inconsistency of conduct or opinion on the part of a State to the prejudice of another is incompatible with good faith. Again, I submit that such inconsistency is especially inadmissible when the dispute arises from bilateral treaty relations.

A secondary basis of the principle is the necessity for security in contractual relationships. A State bound by a certain treaty to another State must rest in the security that a harmonious and undisturbed exercise of the rights of each party and a faithful discharge of reciprocal obligations denote a mutually satisfactory state of things which is permanent in character and is bound to last as long as the treaty is in force. A State cannot enjoy such a situation and at the same time live in fear that some day the other State may change its mind or its conduct and jeopardize or deny rights that for a long time it has never challenged. A continuous and uncontroverted fulfilment of a treaty is tantamount to a pledge, a security renewed day by day that the treaty is valid and effective as signed, intended and understood by the parties. Such a security must needs be upheld as an indispensable element of fruitful harmony in all treaty relationships.

It may thus be seen that the rule facta sunt servanda cannot be conciliated with the notion of inconsistency in the interpretation and observance of public treaties. Of course, this notion does not conflict with the entirely different question of rebus sic stantibus. Inconsistency condemns two contradictory positions with regard to the same situation existing at the time the binding acts occurred. The clause rebus sic stantibus contemplates two different situations: the one existing when the treaty was signed and the new one created by conditions and circumstances posterior to the treaty. But even in the case of ordinary, non-contractual relations between States the rule of consistency must be observed and a State cannot challenge or injure the rights of another in a manner which is contrary to its previous acts, conduct or opinions during the maintenance of its international relationships.

Finally, it may be averred that, as in the case of prescription, the principle is also rooted in the necessity of avoiding controversies as a matter of public policy (interest rei publicize ut sit finis litium). By condemning inconsistency a great deal of litigation is liable to be avoided and the element of friendship and co-operation is strengthened in the international community.

While refraining from discussing the question whether the principle of the binding effect of a State's own acts with regard to rights in dispute with another State is or is not part of customary [p 43] international law, I have no hesitation in asserting that this principle, known to the world since the days of the Romans, is one of the "general principles of law recognized by civilized nations" applicable and in fact frequently applied by the International Court of Justice in conformity with Article 38, para. 1 (c), of its Statute.

Cases in which the International Court of Justice, the Permanent Court of International Justice or arbitration tribunals have applied or recognized the principle above discussed.

1. Express agreement or recognition

In the case of the Award of the King of Spain, Honduras v. Nicaragua (i960), this Court said:

"No question was at any time raised in the arbitral proceedings before the King with regard either to the validity of his designation as arbitrator or his jurisdiction as such. Before him, the Parties followed the procedure that had been agreed upon for submitting their respective cases. Indeed, the very first occasion when the validity of the designation of the King of Spain as arbitrator was challenged was in the Note of the Foreign Minister of Nicaragua of 19 March 1912. In these circumstances the Court is unable to hold that the designation of the King of Spain as arbitrator to decide the boundary dispute between the two Parties was invalid."

And further on the Court declared:

"In the judgment of the Court, Nicaragua, by express declaration and by conduct, recognized the Award as valid and it is no longer open to Nicaragua to go back upon that recognition and to challenge the validity of the Award." {I.C.J. Reports, pp. 207, 213.)

In his Separate Opinion in the same case Judge Sir Percy Spender said:

"I do not find it necessary to determine whether the King's appointment involved any non-compliance with the provisions of the Treaty. Although I incline strongly to the view that the appointment was irregular, this contention of Nicaragua fails because that State is precluded by its conduct prior to and during the course of the arbitration from relying upon any irregularity in the appointment of the King as a ground to invalidate the Award." (Ibid., p. 219.)

In the course of its Advisory Opinion concerning the Jurisdiction of the European Commission of the Danube the Permanent Court of International Justice stated that: [p 44]

"as all the Governments concerned in the present dispute have signed and ratified both the Treaty of Versailles and the Definitive Statute, they cannot, as between themselves, contend that some of its provisions are void as being outside the mandate given to the Danube Commission under Article 349 of the Treaty of Versailles". (P.C.I.J., Series B, No. 14, p. 23.)

In the Eastern Greenland case (1933), the Permanent Court of International Justice declared:

"Norway reaffirmed that she recognized the whole of Greenland as Danish; and thereby she has debarred herself from contesting Danish sovereignty over the whole of Greenland".

The Court accordingly decided that the "Ihlen declaration" was binding on Norway and barred a subsequent Norwegian attitude contrary to its notified intent. (P.C.I.J., Series A/B, No. 53, pp. 70-71.)

The Serbian Loans case is thus reported by Bowett ('Estoppel before International Tribunals", British Year Book of International Law, 1957):

"In the Serbian Loans case the question arose whether in accepting payment of interest upon the loans in French francs, as opposed to 'gold francs', the French bondholders had represented that they were prepared to accept payment in French francs. If they had, despite the derogation from the terms of the loan, it was arguable that they were henceforth estopped from claiming payment according to the strict terms of the loans."

On this point the Permanent Court said:

"... when the requirements of the principle of estoppel to establish a loss of right are considered, it is clear that no sufficient basis has been shown for applying the principle in this case. There was no clear and unequivocal representation of the bondholders upon which the debtor State was entitled to rely and has relied." (P.C.I. J., Series A, Nos. 20-21, p. 39.)

In the Shufeldt case (1930), the United States contended that Guatemala, having for six years recognized the validity of the claimant's contract, and received all the benefits to which she was entitled thereunder, and having allowed Shufeldt to continue to spend money on the concession, was precluded from denying its validity, even if the contract had not received the necessary approval of the Guatemalan legislature. The Arbitrator held the contention to be "sound and in keeping with the principles of international law". (Cheng, General Principles of Law, Ch. 5, C, p. 143.)
2. Recognition by conduct and express agreement

In The Pious Fund of California (1902) it was contended by the United States that Mexico was estopped by its conduct from denying [p 45] the right of the Mixed Commission of 1868 to settle the entire question of the California Fund. They urged that throughout the whole dispute, both before and after the decision of the umpire, Mexico impliedly and by a uniform conduct conceded to that commission full powers of decision. This conduct consisted in the ratification, in 1872 and 1874, of the conventions providing for the extension of time within which the joint Commission should settle the claims brought before it, and also in other acts of the agents of Mexico. (Lauterpacht, Private Law Sources and Analogies of International Law, p. 248.)

3. Passiveness before adverse acts. Abandonment of rights

The binding effect of passiveness or inaction before acts contrary to what a State believes or pretends to believe to be its right is vividly set out in the Grisbadarna case (1909) between Norway and Sweden, in which the tribunal made the following considerations for adjudicating to Sweden the disputed territory:

"The 'circumstance that Sweden has performed various acts in the Grisbadarna region, especially of late, owing to her conviction that these regions were Swedish as, for instance, the placing of beacons, the measurement of the sea, and the installation of a light-boat, being acts which involved considerable expense and in doing which she not only thought she was exercising her right but even more that she was performing her duty; whereas Norway, according to her own admission, showed much less solicitude in this region in these various regards'. After adverting to the maxim quieta non movere, the tribunal laid further stress on the co-existence of expenditure and acquiescence, in the following words: 'Tne stationing of a light-boat, which is necessary to the safety of navi-gation in the regions of Grisbadarna, was done by Sweden without meeting any protest and even at the initiative of Norway, and likewise a large number of beacons were established there without giving rise to any protests.' " (Scott, Hague Court Reports, 1916, p. 121.)

Circumstances very similar to those of the Grisbadarna case occurred in the controversy over the islands of Minquiers and Ecrehos (1953). At a later stage of the oral proceedings Sir Gerald Fitz-maurice advanced the proposition in these terms:

"[Title to territory is abandoned] by letting another country assume and carry out for many years all the responsibilities and expenses in connection with the territory concerned. Could anything be imagined more obviously amounting to acquiescence, that is in effect abandonment? Such a course of action, or rather inaction, disqualifies the country concerned from asserting the continued existence of the title." (J. C. McGibbon, "Estoppel in International Law", in Int. and Comp. Law Quarterly, 1958, p. 509.) [p 46]

In the Yukon Lumber case a claim was put forward by Great Britain for the value of some timber cut in trespass upon Canadian territory, sold subsequently to the Government of the United States, and used by it in the construction of certain military bridges in Alaska. The United States contended in reply that Great Britain, by the course taken by her officials, was estopped from denying that a full and complete title to the timber had legally vested in the United States, that the Canadian land and timber agent stood by silently and watched the American Government acquire this timber bona fide and continue for six months to pay the instalments due in respect of it, and that, accordingly, Great Britain could not now be heard in a demand that the United States should pay for the timber which it was permitted to acquire under false representations. This plea in support of which a vast number of English and American cases on estoppel was cited, was fully adopted by the tribunal. (Lauterpacht, opus cit., para. 132, p. 280.)

The Arbitrator in the Island of Palmas arbitration declared without taking into consideration the recognition by the Treaty of Utrecht of the position in 1714:

"the acquiescence of Spain in the situation created after 1677 [the establishment of the Dutch position in Sangi] would deprive her and her successors of the possibility of still invoking conventional rights at the present". (J. C. McGibbon, opus cit., p. 506.)

4. Failure to protest

"The duty to protest", says Lauterpacht, "and the relevance of the failure to protest, are especially conspicuous in the international sphere where the normal avenues for ascertaining disputed rights through the compulsory jurisdiction of tribunals are not always available."

In this connection he refers to the Venezuelan Preferential Claims (1902) in the following terms:

"The Award, in addition to the effect which it attributed to the Venezuelan recognition in principle of the justice of the claims of the Blockading Powers, was largely based upon the effect of acquiescence as an estoppel, as the following reasons prefacing the operative part of the Award indicate: 'Whereas the Government of Venezuela until the end of January, 1903, in no way protested against the pretension of the Blockading Powers to insist on special securities for the settlement of their claims... Whereas the neutral Powers ... did not protest against the pretensions of the Blockading Powers to a preferential treatment... Whereas it appears from the negotiations ... that the German and British Governments constantly insisted on their being given guarantees... Whereas the Plenipotentiary of the Government of Venezuela accepted this reservation on [p 47] the part of the allied Powers without the least protest... For these reasons [inter alia] the Tribunal of Arbitration decides and pronounces unanimously.' "

In the Anglo-Norwegian Fisheries case (1951), the International Court of Justice considered that the "prolonged abstention" of the United Kingdom from protesting against the Norwegian sys-tem of straight base lines in delimiting territorial waters was one of the factors which, together with "the notoriety of the facts, the general toleration of the international community, Great Britain's position in the North Sea, her own interest in the question, and her prolonged abstention would in any case warrant Norways' enforcement of her system against the United Kingdom".

In the case of The Lotus, the Court referred to the several instances, quoted in argument, of criminal proceedings in respect of collisions before the courts of a country other than that of the flag of the vessel concerned, and stressed the fact that in these cases the States affected did not object and refrained from protesting. The Court said:

"This fact is directly opposed to the existence of a tacit consent . on the part of States to the exclusive jurisdiction of the State whose flag is flown... It seems hardly probable, and it would not have been in accordance with international practice, that the French Govern-ment in the Ortigia-Oncle-Joseph case and the same Government in the Ekbatana-West-Hinder case would have omitted to protest against the exercise of criminal jurisdiction by the Italian and Belgian Courts, if they had really thought that this was a violation of international law." (P.C.I.J., Series A, No. 10, p. 29.)

5. Failure to reserve rights

In the Russian Indemnity case (1912) Russia claimed interest for the delayed payment of certain indemnity sums provided for in the Treaty of Constantinople of 1879. The Ottoman Government maintained, and the accuracy of this assertion appeared clearly from the correspondence produced before the Court, that although the Russian Government demanded in 1891 the payment of both interest and principal, it did not subsequently reserve its rights to interest on the receipts given by the Embassy or in the notes granting extension of payment, and that the Embassy did not regard the received sums as interest. The award said in this connection: [p 48]

"When the tribunal recognized that, according to the general principles and the custom of public international law, there was a similarity between the condition of a State and that of an individual, which are debtors for a clear and exigible conventional sum, it is equitable and juridical also to apply by analogy the principles of private law common to cases where the demand for payment must be considered as removed and the benefit to be derived therefrom as eliminated. In private law, the effects of demand for payment are eliminated when the creditor, after having made legal demand upon the debtor, grants one or more extensions for the payment of the principal obligation, without reserving the rights acquired by the legal demand."

The Tribunal held accordingly that the Ottoman Government was not liable to pay interest-damages as demanded by Russia. (Lauterpacht, opus cit., pp. 255-260.)

The case of the Pious Fund of California, already mentioned, affords another example of the damage a State may suffer from failure to reserve whatever rights may be liable to be affected in connection with an international agreement. In this case the United States pointed out that Mexico, embarking, in 1868 and in the subsequent conventions, upon the litigation, took the risk of success or failure, and that she could not now, after having lost, question the jurisdiction of the tribunal. They disclaimed the intention of relying upon a mere technicality, but urged that if one party to the dispute contemplates the withdrawing of certain claims from arbitration, it is under the obligation to announce such intention in the beginning in order to enable the opposing party to make such claims the foundation of a separate convention. (Lauterpacht, opus cit., p. 248.)

The Landreau case arbitration (1922) was one in which the rule relative to the necessity of reserving rights was discussed before the tribunal but in this case it was found that there was no cause for applying it to the claimant.

In 1892 Théophile Landreau granted a release to the Peruvian Government cancelling his rights, and the Commission found that the Peruvian Government had been notified of the assignment to his brother Célestin of 30 per cent, of the claim. The Commission stated :

"Of course if there was anything to show that Célestin knew of this release at the time of its exécution and abstained from putting forward his claim, he and his representatives would be estopped from making an}' claim against the Peruvian Government, but there is nothing to show that there was any such acquiescence in this transaction by Célestin." [p 49]

The Commission concluded that there was "no sufficient foundation for inferring that Celestin's representatives are estopped by any conduct on his part from not asserting the right to their 30 per cent, share". (McGibbon, opus cit., p. 505.)

7. Inconsistency

Apart from specific cases of recognition, failure to protest or to reserve rights, passiveness or any form of express or tacit acquiescence, other disputes have been decided against litigant States on the general basis of inconsistency between the claims of States and their previous acts. Inconsistency is (and has been for many years) a practice at which the combined efforts of justice and international harmony must be directed.

Thus, in the case of The Mechanic (C. 1862), it was held:

"Ecuador ... having fully recognized and claimed the principle on which the case now before us turns, whenever from such a recognition rights or advantages were to be derived, could not in honour and good faith deny the principle when it imposed an obligation." (Cheng, opus cit., p. 142.)

In the case of The Lisman (1937), concerning an American vessel which was seized in London in June, 1915, the claimant's original contention before the British Prize Court:

"was not that there was not reasonable cause for seizure, or for requiring the goods to be discharged, but that there was undue delay on the part of the Crown in taking the steps they were entitled to take as belligerents. In a subsequent arbitration in 1937, which took the place of diplomatic claims by the United States against Great Britain, the sole Arbitrator held that:

'By the position he deliberately took in the British Prize Court, that the seizure of the goods and the detention of the ship were lawful, and that he did not complain of them, but only of undue delay from the failure of the Government to act promptly, claimant affirmed what he now denies, and thereby prevented himself from recovering there or here upon the claim he now stands on, that these acts were unlawful, and constitute the basis of his claim.'" (Ibid., pp. 142-147.)

[p 50]
In the Salvador Commercial Co. case (1902), the Arbitral Tribunal, in dealing with the Salvadorian Government contention that the Company did not comply with the terms of the concession, held that:

"It is of course obvious that the Salvador Government should be estopped from going behind those reports of its own officers on the subject and from attacking their correctness without supplementary evidence tending to show that such reports were induced by mistake or were procured by fraud or undue influence. No evidence of this kind is introduced." (Cheng, ibid., p. 147.)

It was held in the Chorzow Factory case (1927) that one of the parties was estopped from pleading the Court's lack of jurisdiction on the ground that:

"it is ... a principle generally accepted in the jurisprudence of international arbitration, as well as by municipal courts, that one party cannot avail itself of the fact that the other has not fulfilled some obligation, or has not had recourse to some means of redress, if the former party has, by some illegal act, prevented the latter from fulfilling the obligation in question, or from having recourse to the tribunal which would have been open to him".

The Representative of the United Kingdom, referring to the passage from the Chorzow Factory case and applying it to the question before the Court, said:

"What is involved is really an application of the principle known in English law as estoppel (or to use what I believe is the equivalent French term preclusion)—to which effect has frequently been given by international tribunals." (McGibbon, opus cit., pp. 480-481.)

Likewise, in the Meuse case (1937), it was held that, where two States were bound by the same treaty obligations, State A could not complain of an act by State B of which itself it had set an example in the past. Nor indeed may a State, while denying that a certain treaty is applicable to the case, contend at the same time that the other party in regard to the matter in dispute has not complied with certain provisions of that treaty. (P.C.I.J., Series A/B, No. 70, p. 25.)

In the Behring Sea arbitration of 1893 between the United States and Great Britain, the Arbitrators expressly found against the United States contention that Great Britain had conceded the Russian claim to exercise exclusive jurisdiction over the fur-seals fisheries in the Behring Sea outside territorial waters; and they were fortified in this conclusion by the fact that the United States, [p 51] as well as Great Britain, had protested against the Russian Ukase of 1821 in which this claim was asserted. The proceedings, as Lord McNair stated:

"demonstrated that some advantage is to be gained by one State, party to a dispute, by convicting the other State of inconsistency with an attitude previously adopted". (McGibbon, opus cit., p. 469.)

In its Judgment in the case concerning the Diversion of Water from the Meuse (1937), the Permanent Court of International Justice found it:

"difficult to admit that the Netherlands are now warranted in complaining of the construction and operation of a lock of which they themselves set an example in the past". (P.C.I.J., Series A/B, No. 70, p. 25.)

The anti-inconsistency rule was also applied by the German-United States Mixed Claims Commission in the Life-Insurance Claims case (1924), when it decided that a State was debarred from asserting claims which, on general principles of law, its own courts would not admit, for instance, claims involving damages which its own municipal courts, in similar cases, would consider too remote. (Cheng, opus cit., p. 143.)

There exist many other cases of international jurisprudence which might be cited as examples of the application of the principle which rejects allegations that are contrary to a State's own acts. Space prevents me from citing any more. I have accordingly limited myself to selecting a few cases which I consider can usefully demonstrate, in the main aspects, the force and flexibility of this principle.

(Signed) R. J. Alfaro.

[p 52]
SEPARATE OPINION OF SIR GERALD FITZMAURICE

Although I am in full agreement with the operational part of the Judgment of the Court, and with its reasoning and language, there are certain matters which I should like to develop futher, and others—not mentioned in the Judgment—which seem to me to require a brief discussion.

Since I have no intention of going over the whole ground again, I shall set out my points seriatim, in order of convenience, and without attempting to establish any particular connecting links between them.

The pre-1904 position

The Judgment states that the Court is not called upon to go into the situation as it existed previous to the treaty settlement of 1904; and this is true inasmuch as the rights of the Parties depend on, or flow from, that settlement, or events subsequent to it. There is however one fact, not referred to in the Judgment, which could have been of decisive importance in this case, namely that, previous to the boundary settlements of the period 1904-1908, the Temple of Preah Vihear was situated in territory that was, at that time, under Siamese sovereignty, because a treaty of 15 July 1867 between France (acting on behalf of Cambodia and Siam (as Thailand was then called) had established a frontier line running well south of the Dangrek range of mountains, across the Cambodian plain. Since the effect of the 1904 treaty settlement was to shift the frontier to the north, and to place it along the general line of the Dangrek range, it follows that, by this settlement, Thailand was giving up territory. As a consequence, there arises a presumption in favorem ejus qui dat that Thailand did not relinquish any territory she cannot be proved to have relinquished. This means that in any conflict between a more northerly and a more southerly frontier line in the region of Preah Vihear, the latter line must be held to prevail, unless the former can be established. I agree with the Court that the former (i.e. the more northerly) line can be, and is, established, for the reasons given in the Judgment; but the foregoing considerations require to be stated in order that the significance of the conclusion may be fully apparent.

The matter is brought into relief in another way. Throughout these proceedings Thailand has contended that, there never having been (as she maintains) any effective delimitation of the frontier in the eastern sector of the Dangrek range, as required by Article 3 [p 53] of the Treaty of 1904, the result (by virtue of Article 1) is automatically to cause the frontier to run along the line of the watershed as ascertained by scientific survey. An interpretation even more favourable to Thailand would however be that, in the absence of the delimitation required by Article 3, in completion of Article 1, the latter provision could not have taken any practical effect, so that no new frontier line under the Treaty of 1904 would have come into existence at all, and the frontier would have remained as it was immediately previous to 1904, with the Temple area in Thailand. Since both these interpretations are favourable to Thailand, and either would have been decisive if the Court had not held that Thailand had in any event, subsequently, and independently, accepted a frontier placing the Temple in Cambodia, it was not necessary to choose between them.

There is another aspect of the pre-1904 situation which is material, namely the considerable evidence in the record of the unsettled state of the frontiers between Siam and French Indo-China (of which Cambodia was then part), which had existed for a long time and was the cause of disturbed relations between France and Siam. This is mentioned towards the end of the Judgment. It is however a point that has to be borne constantly in mind from the start, in assessing what the Parties were really intending to achieve by the frontier settlements of the period 1904-1908, and as indicative of their desire to achieve a settlement that would be definite and durable.

Considerations of a topographical, historical and cultural character

The Court has dismissed these in a sentence, as not being legally decisive. I agree that they are not; but I think it desirable to say why, since these considerations occupied a prominent place in the arguments of the Parties. Such matters may have some legal relevance in a case about territorial sovereignty which turns on the weight of factual evidence that each party can adduce in support of its claim, and not on any more concrete and positive element, such as a treaty. In the present case it is accepted, and indeed contended by both Parties, that their rights derive from the treaty settlement of 1904, and on the subsequent events relative to or affecting that settlement. In consequence, extraneous factors which might have weighed with them in making that settlement, and more particularly in determining how the line of the frontier was to run, can only have an incidental relevance in determining where today, as a matter of law, it does run.

Moreover, for these factors to have any serious influence, it would at least be necessary that they should all point in the same [p 54] direction, and furnish unambiguous indications. This is not the case here. As the Judgment of the Court points out, no certain deduction can be drawn from the desire of the Parties for natural and visible frontiers—the Dangreks in themselves furnished that, and would, in a general way, have done so, whether the line along the Dangreks was a crest, a watershed or an escarpment line. Equally, it is difficult to draw any certain deduction from the siting of the Temple. It overlooks the Cambodian plain: but it faces in the direction of Thailand. Its main access is from the latter direction; but there is also access from the Cambodian side—and this access, because steep and hard, must—precisely for that reason—have been contrived deliberately and of set purpose, contra naturam as it were, since it involved a climb of several hundred metres. Yet difficulty of access is not—or was not—all on one side: there is much evidence in the documentation of the case that the thickness of the jungle on the northern (Thai) side of the Temple had the consequence that visits had to be specially prepared, by the clearing of paths and the blazing of trails. This particular difficulty was much less prominent on the Cambodian side: but what remains certain is that if, though for different reasons and in different ways, access was not easy from either side, it was feasible from both, and was also achieved from both, at varying times and in varying degrees.

As to the Khmer origins of the Temple—this factor (put forward by Cambodia) operates in an equally neutral way, since it seems to be admitted that there are and were, in these regions, populations of Khmer race on both sides of the frontier.

The proceedings of the Mixed Commission under the Treaty of 1904
Although I do not dissent from what the Judgment says under this head, I think many of the facts are so conjectural that it is exceedingly difficult to draw any sure conclusions from them. Various inferences may be more or less reasonable and warranted, but when all is said and done the only certain thing is that the Annex I map was produced in Paris by French topographical officers in November 1907, and was never, as such, seen (much less approved or adopted) by the Mixed Commission, which indeed appears to have ceased to function entirely after about February of that year—or at any rate it did not, after January, hold any meeting of which there is any record. Whether the map was based on any instructions that the Commission had given, or on rough sketches approved by it, must, in the absence of any evidence, remain a matter of surmise. It seems to me therefore that Thailand succeeds on this part of the case, about which it is hardly necessary to say more than that, however respectable the [p 55] provenance of the map was, it must be held to have been a purely unilateral production, not in any way binding on Thailand at the moment of its communication to her, and subject entirely, at that time, to her acceptance or rejection, either in whole or in part.

Thailand's acceptance by conduct of the Annex I line

Had the matter ended with the production of the map; or if the map had never been officially communicated to Thailand; or had been communicated in such a way, or in such circumstances, that no adverse conclusion could be drawn from her failure to react; or had been communicated but rejected, either as a whole, or in relation to Preah Vihear; then Thailand would, in my opinion, have been entitled to a finding in her favour, since I personally consider that there is little reasonable doubt that, in this particular region, the true line of the watershed runs, and ran in 1904, along the line of the escarpment. (Moreover, I could not myself regard the deviation from the line of the watershed at Preah Vihear as being covered by any discretionary powers of adaptation which the Mixed Commission might have possessed; but this matter is not in any event material, since it was not the Mixed Commission as such which made or approved the map.)

The crucial issue in this case is therefore whether Thailand, by her conduct in 1908, and thereafter, in fact accepted the Annex I map line as representing the outcome of the work of delimitation provided for by the Treaty of 1904, knowing how it had been produced; or, more simply, whether Thailand just accepted the line as being the frontier line, accepting also the risk of its possible inaccuracy.

The Judgment of the Court answers these questions in the affirmative, on grounds in which I fully concur. In doing so, I am not unmindful of the fact that acceptance by conduct alone, of an obligation in the nature of a treaty obligation, is not lightly to be presumed; especially where a frontier is in question; and even more so where the frontier line thus said to be accepted involves a departure from the delimitary criterion indicated by the relevant treaty. But if the plea of error or misapprehension is excluded, as I think it has to be (see below), I can place no other interpretation on Thailand's conduct, considered as a whole, than that she accepted this particular line as representing the frontier in this region. Moreover, even negative conduct—that is to' say failure to act, react or speak, in circumstances where failure so to do must imply acquiescence or acceptance—is, in my opinion, quite sufficient for this purpose, if the facts are clear.

I would only add to the views expressed in the Judgment, that [p 56] I cannot accept the plea so eloquently urged on behalf of Thailand that any adherence to the Annex I line would have involved a departure from a solemn treaty obligation. This surely begs the question; for as the Judgment says, it is always open to governments, in their bilateral relations, to agree on a departure of this kind, provided they do so knowingly, or (as I think was Thailand's case here) in circumstances in which they must be held to have accepted, and as it were discounted in advance, the risks or consequences of lack, or possible lack, of knowledge. In the present case, the conduct of each Party, over what was an important matter of common concern to both, was, in my opinion, evidence of, or amounted to, a mutual agreement to accept a certain line as the frontier line. What seems to me therefore really to have occurred was not in the legal 'sense a departure from the treaty provision concerned, but the mutual acceptance of a certain result as being its actual outcome, irrespective of the precise conformity of that outcome with the treaty criterion.

I think it desirable here to mention a point of detail, but one nevertheless liable to give rise to some confusion. Another of the maps communicated to the Siamese authorities covered the Pnom Padang range of mountains which prolongs the Dangrek range eastwards to the river Mekong, and showed a frontier line apparently running along the crest of the Pnom Padang. This was because the Treaty of 1904, while prescribing a watershed line for the Dangreks, prescribed a crest line for the Pnom Padang, and the actual delimitation was carried out by the Mixed Commission set up under that Treaty. The subsequent boundary Treaty of March 1907, however, prescribed a watershed line for the Pnom Padang as well as for the Dangreks. But already in the meantime, the first (1904) Mixed Commission had (see minutes of its meeting of 18 January 1907) adopted the crest line (though the Commission seems in this region to have regarded the crest and watershed lines as coinciding). As far as I can understand the matter, the result was that although it was strictly part of the task of the second (1907) Mixed Commission to delimit the frontier along the Dangrek and Pnom Padang ranges, it only delimited the western Dangrek sector (the eastern sector being the task of the first Commission), and did not delimit the Pnom Padang at all. The crest line delimitation carried out by the first Commission in the Pnom Padang region therefore stood. There seems thus to have been a tacit understanding between the Governments that the relevant provisions of the 1907 Treaty would to this extent be ignored, since a delimitation, even though not the one provided for in this latter Treaty, had already been carried out. Here again, therefore, the Governments accepted the map line as being the line of the frontier, even though it did not correspond [p 57] with the latest treaty provision on the subject. This is a minor matter, but it illustrates very aptly how the Governments did not consider themselves as necessarily tied down to the treaty criteria in what they finally accepted as the frontier line.

The question of error

The Court has dealt very fully with this matter, but it is so central to the whole issue in this case that I desire to make some additional remarks about it.

In the interests of the stability of contracts, the principle of error as vitiating consent is usually applied somewhat strictly; and I consider that this approach is also the correct one in international law, in the interests of the stability of treaties, and of frontier lines established by treaty or other forms of agreement. That there was (as I think) an error in the map by ,reference to the true watershed line does not necessarily mean that Thailand was herself under any misapprehension, nor that, if she was, she can, in law, now plead the fact. The Siamese authorities, in 1908 and thereafter, cannot possibly have failed to realize that the Annex I map showed Preah Vihear as being in Cambodia, since it so clearly did; and for the reasons given in the Judgment of the Court, the fact that, at this time, the Siamese authorities may have attached no importance to the Temple, or may have failed to realize the importance it would eventually assume for them, is legally quite irrelevant. This could never, per se, be a legal ground for claiming frontier rectifi-cation.

The sole remaining question therefore is whether the Siamese authorities, if (as the Judgment holds) they accepted that Preah Vihear should be attributed to Cambodia (as part of French IndoChina), did so in the mistaken belief—and (as Thailand alleges) only on the basis of such a belief—that the line on the map corresponded to the watershed line.

Even if the Siamese authorities of that date were under such a misapprehension, there are, in my opinion, two decisive reasons why Thailand cannot now rely on or plead the fact. The first arises as follows.

It was the Siamese Government itself which, with the assent, and actually at the suggestion of the Siamese members of the Mixed Commission, formally requested that the work of preparing the maps of the frontier areas should be carried out by the French topographical officers. It was the same in connection with the work of the second Mixed Commission under the Treaty of 1907. In the [p 58] eastern Dangrek sector moreover, the Siamese authorities did not even cause the French officers doing the survey work to be accompanied by a Siamese officer, as they could have done, and as was in fact done in other cases (and it was actually a French officer of Cambodian race who did the survey work in the eastern Dangrek sector, as the Siamese members of the Mixed Commission perfectly well knew). The despatch from the Siamese Minister in Paris enclosing the series of maps, of which the Annex I map was one, also stated in the clearest possible terms that they were the maps produced by the French officers in response to "the Siamese Commissioners" request. The maps were then communicated to the Siamese members of the Mixed Commission, who of course equally knew this, and further would have known how far, if at all, the maps were based on work done or approved, or on instructions given by, the Commission itself.

It is apparent, therefore, that no one on the Siamese side could have been under any misapprehension as to the provenance of these maps. Furthermore, is is evident that the Siamese authorities deliberately left the whole thing to the French elements involved, and thus accepted the risk that the maps might prove inaccurate in some respects. Consequently, it was for them to verify the results, if they wished to do so, in whatever way was most appropriate in the circumstances, e.g. by consulting neutral experts. If they did not (for whatever reasons) wish to do this, then they had to abide by these results. The formal request for extra copies for the use of the provincial Governors shows that, in any event, the case was not one of a mere passive reception of these maps by the Siamese authorities.

The explanation of all this, there can -be no reasonable doubt, is that, in effect, everyone on the Siamese side relied on the skill and good faith of the French topographical officers producing the maps. There can equally be no doubt that the latter acted in complete good faith, used all their skill, and fully believed that the watershed in the Preah Vihear region ran as indicated by the An-nex I line. One may sympathize with Siam's lack of topographical and cartographical expertise at this time, but one is dealing with sovereign independent States to whom certain rules of law apply; and it remains the fact that, in the absence of any question of lack of good faith, the legal effect of reliance on the skill of an expert is that one must abide by the results—in short, a principle akin to that of caveat emptor is relevant. This is so in all walks of life. A man who consults a lawyer, doctor, architect, or other expert, is held (in the absence of fraud or negligence—not here in question) to accept the possibility that the expert may be mistaken in the advice he gives, or less than perfect in the work he does. Like all human beings, he is fallible. Except in cases in which the doctrine of "absolute" risk or liability prevails, the law [p 59] as a general rule affords no remedy against errors made in good faith and without negligence by duly qualified experts. The dangers of giving expert advice could not otherwise be accepted. The French officers in this case were of course fallible. They for instance (and both Parties were agreed about this) made an error over the course of the O'Tasem stream, which must have affected the whole question of how the watershed line ran in the Preah Vihear region. The authorities of French Indo-China were unaware of this error. They accepted the map as correct. Equally, the Siamese authorities, knowing the character and provenance of the map, being in a position to consult their Commissioners who had received it, or experts of their own choice, made no objection, and raised no query, in relation to a line which was clearly intended to represent and constitute the line of the frontier in this region, and which anyone looking at it must have seen at once placed Preah Vihear on the Cambodian side of the line. Today Thailand says the map was erroneous and that she was under a misapprehension about it. But the Siamese authorities of that date plainly accepted the risk that just such an error as this might in time be discovered: and whoever does that, must be held thereby also, and in advance, to have accepted such errors as do in fact eventually come to light.

The other decisive reason why it is not possible to receive Thailand's plea that she mistakenly believed the Annex I line to correspond to the line of the watershed, and that she only on that basis accepted the siting of Preah Vihear in Cambodia, is, as the Judgment of the Court points out, that this plea is totally inconsistent with her attitude over her "acts on the ground", which she puts forward as evidence that she considered herself to have sovereignty over Preah Vihear and had never accepted the Annex I line; for if this was so, she must have regarded the map line as erroneous, and the map as showing Preah Vihear in Cambodia for that reason only. It does not make any difference that the Court has found that Thailand's acts on the ground did not in fact suffice to demonstrate her non-acceptance of the map line. The inconsistency with the plea of mistaken belief lies in the very contention that they did.

Thailand's "acts on the ground"

If Thailand's attitude respecting her acts on the ground debars her from pleading error over the watershed question, she remains fully entitled to put them forward as evidence of a belief on her part that she had sovereignty over Preah Vihear, and did not accept [p 60] the Annex I line in that region. But like the Court, I do not find these acts really convincing in that sense. Thailand has, I know, produced an impressive volume of evidence of local administrative activity relative to Preah Vihear; but it is not clear to me just what legal value can be attached to it. I have already drawn attention to the fact that previous to the 1904 treaty settlement, the Preah Vihear region (not in isolation of course, but as part of the eastern Dangrek sector) was, and had since 1867 been, under Siamese sovereignty, because the frontier at that time ran south of the whole Dangrek range. In view of this, it was perhaps to be expected (and would not in itself signify greatly) that in this rather remote region, and because of the difficulties of communication with Bangkok which must then have existed, the local officials and authorities of Khukhan province should, for a time, have continued, at and near Preah Vihear, to perform those acts and carry out those activities which they had been accustomed to perform and carry out for some time past. If this was the position, no very positive inference can be drawn from it. It is true that the Siamese authorities did take steps to make the frontier changes known locally; but, in this region, realization of them may have been slow to come through. There may for a time have been an element of fluidity in the local situation; but the real attitude of Siam as a State must, for the reasons given in the Judgment of the Court, be taken to be that evinced in the course of, and following upon, the visit of Prince Damrong in 1930—by far the most significant incident in this part of the case. To me it seems to have constituted a tacit recognition of Cambodian sovereignty over Preah Vihear, and the existence of possible reasons why Siam did not protest cannot, in law, alter the fact.

I also could not help being struck by the evidence of one of Thailand's own expert witnesses—a patently honest and reliable one, it seemed to me—to the effect that, in the course of a visit to this region in July 1961, during which he spent eleven days in carrying out a survey of the Temple area, he saw no sign of the inhabitants, rice cultivations, or forestry or other activities, that figure so prominently in the evidence furnished by Thailand respecting the period following on the treaty settlements of 1904-1908. This witness, when cross-examined on behalf of Cambodia, was asked whether he saw any people living between Preah Vihear and the nearest village on the Thai side—a distance of 10-15 kilometres— and he answered "No, there is [sc. he saw] nobody living there". When asked whether he saw any people on Mount Preah Vihear itself, he said that, apart from the Thai police post, and one guard at the Temple, he saw "occasionally a few visitors ... or tourists". When asked whether he saw any people cultivating rice, he said [p 61]

"No. This area is covered by jungle forests and there is no rice cultivation". Asked whether he saw any woodcutters or foresters about, he replied "During the eleven days I stayed there I did not see anybody". In re-examination on behalf of Thailand, no questions were put to the witness on these points.

It is obviously not permissible from this evidence, particularly on the basis of so short a stay, to draw any definite conclusion as to the situation existing at the earlier period. But even in eleven days it is possible to see if, in a restricted area, there are any habitations, cultivations, forestry work in progress, and so on. It seems therefore reasonable to infer—taking the scale of Siamese activity in this area, in the period following on the treaty settlement, to have been as indicated in the evidence furnished by Thailand— that it must since have undergone a notable diminution.

The Treaties of 1925 and 1937
These Treaties, the bearing and effect of which was much discussed in the written and oral proceedings, have, in my opinion, only a limited, though weighty significance in this case, namely as indicative of the importance the Parties attached to having stable and durable frontiers. This was shown by the fact that frontier revision was, in terms, excluded from the revisionary processes which were otherwise one of the main objects of these Treaties. The Court has made this fact the basis of a finding, with which I fully agree, that it is reasonable to assume from this feature of the Treaties that, by the boundary settlements of the period 1904-1908, the Parties were equally seeking stability and durability, and that this factor should therefore prevail in resolving any doubts in favour of, or against, a part of the frontier the validity of which is now called in question.

It is a general principle of law, which has been applied in many contexts, that a party's attitude, state of mind or intentions at a later date can be regarded as good evidence—in relation to the same or a closely connected matter—of his attitude, state of mind or intentions at an earlier date also; provided of course that there is no direct evidence rebutting the presumption thus raised. Similarly—and very important in cases affecting territorial sovereignty—the existence of a state of fact, or of a situation, at a later date, may furnish good presumptive evidence of its existence at an earlier date also, even where the later situation or state of affairs has in other respects to be excluded from consideration (Judge Huber in the Island of Palmas case, Reports of International Arbitral Awards, Vol. II, at p. 866; and see also the separate Opinion of [p 62] Judge Basdevant in the Minquiers and Ecrehos case, I.C.J. Reports 1953, at p. 76 ff.).

Cambodia however claimed another effect for the Treaties of 1925 and 1937, namely that by confirming the frontiers as already established, they imparted a new and independent treaty basis to the Annex I line, thereby validating it, even if it was not valid before. I do not think this contention well-founded. Such a confirmation of the existing frontiers no doubt implied that frontiers did exist, and possibly also that they existed and were complete at all points of contact between the two countries; but this could not, by itself, say anything at all as to what these frontiers were, or how exactly they ran. A confirmation only confirms what is; it cannot per se alter, add to, or detract from the latter, which must be ascertained ab extra—in this case by reference to the previous treaty settlements and the events relevant to them. The confirmation was evidence of the importance the Parties attached to the frontiers, but otherwise it left matters as they were, whatever they were.

The principle of preclusion and estoppel

The Court has applied this principle in the present case to the effect that even if there could be any doubt as to whether Thailand did originally accept the Annex I map and line, so as to become bound by it, she is precluded by her subsequent conduct from now asserting her non-acceptance. With this conclusion I agree (it being postulated, for reasons already given, that no error or misapprehension can be pleaded). But the Court only glances at the matter, which needs a good deal of development.

The principle of preclusion is the nearest equivalent in the field of international law to the common-law rule of estoppel, though perhaps not applied under such strict limiting conditions (and it is certainly applied as a rule of substance and not merely as one of evidence or procedure). It is quite distinct theoretically from the notion of acquiescence. But acquiescence can operate as a preclusion or estoppel in certain cases, for instance where silence, on an occasion where there was a duty or need to speak or act, implies agreement, or a waiver of rights, and can be regarded as a representation to that effect (see the cases, and the quotation from an Opinion of the British Law Officers, cited in Dr. D. W. Bowett's article, "Estoppel before international tribunals and, its relation to acquiescence", in the British Year Book of International Law for 1957, at pp. 197-201; and see also Lord McNair's Law of Treaties, 1961, p. 488). On that basis, it must be held in the present case that Thailand's silence, in circumstances in which silence meant acquiescence, or acted as a representation of acceptance of the map [p 63] line, operates to preclude or estop her from denying such acceptance, or operates as a waiver of her original right to reject the map line or its direction at Preah Vihear.

However, in those cases where it can be shown that a party has, by conduct or otherwise, undertaken, or become bound by, an obligation, it is strictly not necessary or appropriate to invoke any rule of preclusion or estoppel, although the language of that rule is, in practice, often employed to describe the situation. Thus it may be said that A, having accepted a certain obligation, or having become bound by a certain instrument, cannot now be heard to deny the fact, to "blow hot and cold". True enough, A cannot be heard to deny it; but what this really means is simply that A is bound, and, being bound, cannot escape from the obligation merely by denying its existence. In other words, if the denial can be shown to be false, there is no room or need for any plea of preclusion or estoppel. Such a plea is essentially a means of excluding a denial that might be correct—irrespective of its correctness. It prevents the assertion of what might in fact be true. Its use must in consequence be subject to certain limitations. The real field of operation, therefore, of the rule of preclusion or estoppel, stricto sensu, in the present context, is where it is possible that the party concerned did not give the undertaking or accept the obligation in question (or there is room for doubt whether it did), but where that party's subsequent conduct has been such, and has had such consequences, that it cannot be allowed to deny the existence of an undertaking, or that it is bound.

The essential condition of the operation of the rule of preclusion or estoppel, as strictly to be understood, is that the party invoking the rule must have "relied upon" the statements or conduct of the other party, either to its own detriment or to the other's advantage. The often invoked necessity for a consequent "change of position" on the part of the party invoking preclusion or estoppel is implied in this. A frequent source of misapprehension in this connection is the assumption that change of position means that the party invoking preclusion or estoppel must have been led to change its own position, by action it has itself taken consequent on the statements or conduct of the other party. It certainly includes that: but what it really means is that these statements, or this conduct, must have brought about a change in the relative positions of the parties, worsening that of the one, or improving that of the other, or both.

The same requirement, that a change or alteration in the relative positions of the parties should have been caused, covers also certain [p 64] other notions usually closely associated with the principle of preclusion or estoppel, such as for instance that the one party must have "relied" on the statements or conduct of the other; or that the latter must, by the same means, have "held itself out" as adopting a certain attitude; or must have made a "representation" of some kind. These factors are no doubt normally present; but the essential question is and remains whether the statements or conduct of the party impugned produced a change in relative positions, to its advantage or the other's detriment. If so, that party cannot be heard to deny what it said or did.

Applying this test to the circumstances of the present case, there can be little doubt that' Cambodia's legal position was weakened by the fact that (although a striking assertion of her sovereignty had been manifested on the occasion of Prince Damrong's visit in 1930) it was not until 1949 that any protest on the diplomatic level was made about local acts of Thailand in violation, or at any rate in implied denial, of that sovereignty. But France (exercising the protectorate) was entitled to assume from the conduct of the central Siamese authorities that the latter accepted the frontier as mapped at Preah Vihear. On that basis, but oh that basis only, France could safely ignore the activities of local Siamese authorities, and (the war period being ruled out, as I think it must be in this case) confine her diplomatic action, as she seems to have done, to cases clearly involving the central Siamese authorities.

Similarly, it was only on the basis of a justifiable assumption of Thailand's acceptance of the frontier line as mapped that a comparatively low level of administrative activity on the part of France and Cambodia at Preah Vihear would have been compatible with the upkeep of sovereignty. It is an established principle of international law that, especially in wild or remote regions, comparatively few acts are necessary for that purpose where the title does not primarily depend on the character or number of those acts themselves, but derives from a known and independent source, such as a treaty settlement. On the basis therefore of the acceptance of the map line by Thailand, as part of the treaty settlement, there would, in the upkeep of Cambodian title, have been no need (in respect of such a locality as that of the Temple area) to perform any but the most minimal and routine acts of administration. Clearly, if Thailand could now be heard to deny this acceptance, the whole legal foundation on which the relative inactivity of France and Cambodia in this region was fully explicable would be destroyed.

In addition to the foregoing considerations, it may be useful to recall a deliberately non-technical statement of the matter given [p 65] by a former Judge of the Court (writing in another capacity), as follows:

"A State cannot be allowed to avail itself of the advantages of the treaty when it suits it to do so and repudiate it when its performance becomes onerous. It is of little consequence whether that rule is based on what in English law is known as the principle of estoppel or the more generally conceived requirement of good faith. The former is probably not more than one of the aspects of the latter." (Lauterpacht, Report on the Law of Treaties, U.N. Document A/CN.4/63 of 24 March 1953, p. 157.)

The question of interpretation—watershed clause versus map line

The Court has dealt fully with this matter, although indicating in effect that, given the main basis of the Judgment, it does not strictly arise, because the Parties themselves resolved any possible conflict when they accepted the map line as being the outcome of the work of delimitation even if it might not in all respects follow the watershed line. I think the Court was nevertheless right to consider how any conflict should, as a matter of ordinary treaty interpretation, be resolved, for the following reason.
It would have been open to Thailand in the present proceedings to have adopted a different course from the one she in fact followed. Instead of denying, she might have admitted acceptance of the map as representing the outcome of the work of delimitation, and also that the map became part of the treaty settlement. Having admitted that, however, it would still have been open to Thailand to contend that, precisely because the map had become part of the settlement, any conflict arising between it and a clause of the Treaty must fall to be resolved by the ordinary processes of treaty interpretation, and that Thailand must be entitled to the benefit of those processes, just as would be the case if an inconsistency were discovered between two provisions of the Treaty itself. On that basis, even if Thailand admitted her acceptance of the map, it was open to her to argue that in a conflict between a treaty clause that says "watershed" and a map that says something different, the former must prevail. It was therefore necessary for the Court to deal with the matter on that basis.

There is of course no general rule whatever requiring that a conflict of this kind should be resolved in favour of the map line, and there have been plenty of cases (some of which were cited before the Court) where it has not been, even though the map was one of the instruments forming part of the whole treaty settlement (as here), and not a mere published sheet or atlas page—in which case it would, in itself, have no binding character for the parties. The question is one that must always depend on the interpretation of [p 66] the treaty settlement, considered as a whole, in the light of the circumstances in which it was arrived at. So considered in the present case, I agree with the Court that, in this particular instance, the question of interpretation must be resolved in favour of the map line.

The course of the watershed line

According to the basis adopted for the Judgment of the Court (with which basis I agree), it becomes unnecessary to consider how the watershed line really runs at Preah Vihear. I nevertheless desire to say that the expert evidence on this subject, written and oral, convinced me personally that the watershed line runs (and ran also in the period 1904-1908) as contended for by Thailand.

(Signed) G. G. Fitzmaurice.

[p 67]
DISSENTING OPINION OF JUDGE MORENO QUINTANA

[Translation]

To my sincere regret I am unable to agree with the majority of my colleagues in the decision of this case. It is my firm conviction that sovereignty over the portion of territory of the Temple of Preah Vihear belongs to Thailand. The dissenting opinion which I express hereunder gives the reasons on which it is based. In American international law questions of territorial sovereignty have, for historical reasons, a place of cardinal importance. That is why I could not, as a representative of a legal system, depart from it.

***
The present case is concerned with sovereignty over a portion of territory on which are situated the ruins of a temple known as Preah Vihear.

Both Cambodia and Thailand claim, by virtue of the initial stipulation of a treaty, to be the domina terrarum of the portion in question. This stipulation is that contained in Article i of the Treaty concluded on 13 February 1904 between France, which at that time represented Cambodia under a protectorate regime, and Thailand, then the Kingdom of Siam. It provides that the frontier between the two countries at the point at issue "follows the watershed between the basins of the Nam Sen and the Mekong, on the one hand, and the Nam Moun, on the other hand, and joins the Pnom Padang chain, the crest of which it follows eastwards as far as the Mekong". No reference is made to the temple of Preah Vihear.

It is this provision of the treaty which constitutes the legal title of the Parties to sovereignty over the temple area. It is consequently the intertemporal law applicable to this case. The frontier delimitation work prescribed by Article 3 of the treaty and the line shown on maps are no more than its physical implementation and may in consequence be vitiated by error. To take a decision in this case on the basis of assumptions or hypotheses in order to resolve the question at issue would not seem very consistent with the rules of judicial settlement. There has been no conclusive evidence showing any tacit recognition by Thailand of the alleged Cambodian sover-eignty over the area in question. It is the facts, clear facts, which must be taken into account.

Cambodia, the applicant in this case, alleges that sovereignty over the Preah Vihear area belongs to it, that it has never abandoned that sovereignty and that Thailand has never performed there [p 68] any acts of sovereignty capable of displacing that of Cambodia. Cambodia also asks the Court to provide for the withdrawal of the armed forces stationed by Thailand in the temple ruins since 1954. The respondent, Thailand, in the submissions of its Counter-Memorial, makes a counter-claim asking the Court to declare that sovereignty over the Preah Vihear area belongs to Thailand. It is thus for each Party to furnish proof of its allegation.

***
Consequently, the case amounts to interpreting the said Article 1 of the 1904 Treaty according to its natural and ordinary meaning. There is no legal problem basically involved; the rule Pacta sunt servanda, which is at the root of international law, is not contested by the Parties. The ensuing situation is a frontier hitherto undetermined at the place in issue. It is governed by a single ques-tion of fact: is the temple of Preah Vihear situated south of the line stipulated by the treaty—that is to say, in Cambodian territory—or north of it, which would put the temple in Thai territory? The decisive geographical factor in this case is the line of the watershed or divortium aqnarum between two river basins. A watershed is not an intellectual abstraction; it is the result of the characteristics of the terrain, and it is always a topographical feature— the crest of a mountain, the ridge of an escarpment or the height of a piece of land—which will form a natural watershed.

The task of the Court in this case is fully compatible with the essential function of declaring the law conferred upon it by Article 38 of the Statute. Under Article 36, paragraph 2 (a), the interpretation of an international treaty is one of the Court's specific functions. This certainly does not mean that, by stating what is the watershed referred to in the said Article 1, the Court takes the place of a delimitation commission, still less that it marks a new frontier line on the ground.

Acting in this way, the Court responds precisely to what the Parties are asking of it. Its decision falls within the limits of its jurisdiction and not outside it. Both Thailand and Cambodia ask it to declare that sovereignty over the Preah Vihear area belongs to them. The Court cannot refuse to discharge its judicial task. It recalled in its Judgment in the Asylum case "the principle that it is the duty of the Court not only to reply to the questions as stated in the final submissions of the parties, but also to abstain from deciding points not included in those submissions" (I.C.J. Reports 1950, p. 402). This sound rule is and always has been the basis of the Court's work. [p 69]

Once the Court has indicated what it considers to be the correct line of the watershed, it will be for the Parties to determine how that line is to be given expression on the ground. The latter task is of a technical nature, and not within the judicial field which belongs to the Court.

***

An instrument of later date than the 1904 Treaty—the protocol annexed to the new treaty concluded on 23 March 1907 between France and Siam—approved the frontier line adopted by a Delimitation Commission on 18 January of that year. This line however is not indicated in detail in the minutes of the Commission. It appears only upon a map which Cambodia submits as Annex I to its Memorial and on which, pursuant to some unknown decision, the temple of Preah Vihear is shown on the Cambodian side. This map bears no date and is not signed by any authorized experts, still less by the contracting parties to the new treaty. It was published by Barrere, a Paris geographical publisher, acting apparently on behalf of only one of the two Commissions—the French and the Siamese—which were to survey the frontier line. In the top left-hand corner of the map it is stated that the work on the ground was carried out by two captains of the French colonial army, Captains Kerler and Oum, two technicians, therefore, who represented in principle only one of the Parties concerned and who should at least have had recorded on the map itself the capacity in which they were acting.

Further, the expert investigations carried out by both Parties (see in particular the D.A.I. Report of 23 October 1961 submitted by Cambodia) agree to the effect that the Annex I frontier line departs considerably from the watershed line. Geography is not however a subject which is open to divergent interpretations. It reflects one and the same reality. Moreover the closest possible scrutiny of the minutes of the meetings of the Mixed Franco-Siamese Delimitation Commissions held between 1905 and 1907 does not yield any result as regards which side of the frontier Preah Vihear is situated on.

Now, territorial sovereignty is not a matter to be treated lightly, especially when the legitimacy of its exercise is sought to be proved by means of an unauthenticated map. As was said by Max Huber in his Arbitral Award in the. Island of Palmas case: "... only with the greatest caution can account be taken of maps in deciding a question of sovereignty... If the Arbitrator is satisfied as to the existence of legally relevant facts which contradict the statements of cartographers whose sources of information are not known, he can attach no weight to the maps, however numerous and generally appreciated they may be ... a map affords only an indication—and [p 70] that a very indirect one—and, except when annexed to a legal instrument, has not the value of such an instrument, involving recognition or abandonment of rights" (see U. N., Reports of International Arbitral Awards, vol. II, pp. 852, 853, 854).

In the present case, Annex I to the Memorial is not the valid annex to the protocol which approved the Cambodian-Siamese frontier line in the Dangrek region. Above all, its being signed was an indispensable condition of its validity, since, as appears from its minutes, the Mixed Delimitation Commission stipulated at its second meeting on 7 February 1905: "According to the procedure proposed by Commandant Bernard at the first meeting, the Commission should first carry out a general reconnoitring, gather information of various kinds which would make it possible to fix on the spot the points through which the frontier passed, then mark that frontier on the map and finally, if necessary, discuss whether it was correct and make any essential modifications. As soon as agreement was reached, the frontier line would have been finally determined by the members of the two Commissions signing the map on which the frontier had been marked" (see Annex 12 (a), Thai Counter-Memorial, p. 58).

***

It has been contended that Thailand's silence with regard to the publication of the Annex I map implied recognition of the line fixed by that map. But silence has consequences in law only if the party concerned is under an obligation to make its voice heard in response to a given fact or situation. It would thus have been necessary to show that Thailand was under such an obligation in respect of an act devoid in itself of legal significance. A well-established rule was moreover embodied in Article 29 of the Treaty of Versailles of 28 June 1919. This rule states that, when there is a discrepancy concerning a frontier delimitation between the text of a treaty and maps, it is the text and not the maps which is final. This being so, and until conclusive evidence establishes where Preah Vihear is situated, Article 1 of the 1904 Treaty, which stipulates the watershed as the territorial boundary of the two countries, supports the interpretation of-Thailand equally as well as that of Cambodia. The same can be said of clause I of the protocol annexed to the 1907 Treaty, which likewise makes no reference to Preah Vihear, but mentions the watershed.
Other considerations adduced by the Parties must be evaluated by an international tribunal at their correct significance. These considerations relate to the maps belonging to one or other of the Parties and the sketches, photographs, accounts of journeys, [p 71] record-cards and other material. As evidence they have only a complementary value which is in itself without legal effect. This applies especially to the maps put in by Cambodia and which had been drawn up by official Thai services, on which Preah Vihear is shown in Cambodian jurisdiction. These maps do not appear at all conclusive, being based upon the Annex I map which is not authoritative and does not show the true watershed line. It is possible to recognize expressly or tacitly a given de jure or de facto situation, but not a situation vitiated by a technical error. An error remains an error and cannot by repetition make good acts of later date that are based upon that error. That is the only significance that should be attached to the question of error in the present case, where it does not have the significance of vitiation of consent, the existence of which is possible in a legal instrument but not in a map.

***

Nor is it necessary to consider international instruments of later date than 1904 and 1097, since they make no special reference to Preah Vihear and Thailand has not questioned them. These include the Franco-Siamese Treaties of 14 February 1925 and 7 December 1937 and the Settlement Agreement of 17 November 1946 which restored the frontier status quo prior to the Tokyo Convention of 9 May 1941 adjusting the frontier between Thailand and Cambodia. On the other hand, any acts that may have been carried out either by Cambodia or by Thailand in the exercise of their sovereignty over the portion of territory in question could be important having regard to the doubt created by this case. Their legal value is indicated by sufficiently well-established precedents.

An analysis of these acts need not go back to the historical origins of the building of the temple of Preah Vihear nor need it take account of the religious role which the temple is said to have played for both the Siamese and the Cambodian peoples. The question to be decided does not arise before 1904, the date of the treaty which fixed the disputed frontier. Thailand says that the elevated situation of the temple, built upon a plateau, makes it difficult of access from the plain situated to the south and on the Cambodian side of the chain, while it is far more easily accessible from the north, where Thailand is situated. This contention seems to be correct. It is based on a geographical fact which is clearly in favour of the exercise of territorial sovereignty by the country having easy access and not by the country which has not such access. Having regard to the topography of the frontier area, the very suggestion that the Preah Vihear area lies within Cambodian jurisdiction is really contrary to sense. It is in conflict with the principle of natural frontiers which was apparently adopted by the Mixed Delimitation Commission. Apart from this presumption, however, there is not [p 72] adequate evidence in support of the acts of sovereignty allegedly performed at Preah Vihear by either Party.

Cambodia relies on the exercise of territorial powers by France in regard to the Preah Vihear area. It refers to official visits, administrative tours, archaeological expeditions, elephant hunting, the taking of photographs, the despatch of letters, the upkeep of the temple, etc. But these sporadic displays of activity at a spot which was unguarded and consisted of ruins, even it they took place as described by the applicant, would have only a very relative significance so far as territorial sovereignty is concerned. In its turn, Thailand alleges the collection of taxes—which would indeed be a manifestation of sovereignty—but furnishes evidence consisting only of affidavits by officials. The respondent offers evidence of the same kind in regard to other activities carried out by the Thai authorities. Assuming that these manifestations by the two Parties were as described, they would only serve to show the Court that there was a performance of concurrent and reciprocally unnoticed administrative activities. Even if known, these activities would have been the subject of objection or of different interpretations. All this gives the impression that both Cambodia and Thailand lived for more than half a century without being particularly certain of their sovereign rights over the temple area. For this reason the correct application of the 1904 Treaty is the main goal which the Court must seek in this case, by locating on the basis of an adequate expert opinion the watershed between the basins of the Nam Sen and the Mekong, on the one hand, and the Nam Moun on the other hand.

***
This expert evidence was furnished more particularly by Thailand, which, although in principle the respondent State, took the initiative in the matter. Cambodia also played a part in connection with the expert opinion by cross-examining the experts and witnesses of the other Party. From the point of view of the settlement of the case this lends appreciable weight to the results of the investigations of the experts. There are four written reports relating thereto—two by Professor W. Schermerhorn, acting for the International Training Center for Aerial Survey (I.T.C.) of Delft, dated 8 September 1961 and 11 January 1962, and two other reports by Messrs. Doeringsfeld, Amuedo and Ivey (D.A.I.), a private firm established at Denver (Colorado), United States of America, these being dated 23 October 1961 and 21 February 1962. In the course of the hearings the witnesses or experts were closely examined by both Parties. They were M. Suon Bonn, former governor of the [p 73] Cambodian province of Kompong Thorn; Professor Schermerhorn, well-known in Holland and elsewhere for his work on aerial surveying; Mr. Ackermann, who has a high reputation as a topographer, also attached to the Delft Center, and lastly Mr. Verstappen, a well-known geologist and likewise a member of the Center. It was Mr. Ackermann's special merit that he carried out the work of frontier reconnaissance, a task which is described in the Didionnaire de la Terminologie du droit international published in i960 by eminent jurists as "checking on the spot that the boundary marks of a frontier are in fact at the points indicated in the boundary treaties or conventions and shown on the maps annexed to those treaties or conventions" (see p. 514). This Court has also, in its Judgment in the Corfu Channel case, stressed the value of an expert investigation carried out by a procedure similar to that followed in the present case. The Judgment said: "The Court cannot fail to give great weight to the opinion of the Experts who examined the locality in a manner giving every guarantee of correct and impar-tial information" (I.C.J. Reports 1949, p. 21).

A layman in the matters with which the opinion of the experts was concerned as a judge generally is, he has to draw a legal conclusion from a piece of technical work which seems to carry conviction. In general, the opinions of the experts and witnesses for Thailand impressed by their technical precision and the logical nature of their reasoning. Moreover, the official character of the Center, which is connected with the Netherlands Government, confers upon its opinion an objectivity and an authority perhaps greater than could attach to the work of a private firm. However a question is raised by the possibility that, in a critical area which was described, there might be an alternative watershed line to that indicated by Professor Schermerhorn's report. That question is answered by the topographical work carried out on the spot by Mr. Ackermann. The true line of the watershed was indeed the one indicated in the report. Even if the alternative line had been the true line it would still not have left the temple area in Cambodian territory. And it is the question of the sovereignty over the temple that is put to the Court, and no other. The waters of a river basin may run down from a promontory like one on which the temple is situated, but they can never rup up it. That is obvious.

***

What has been said above leads to the following conclusions:

(1) the essential question to be settled by the Court—since neither Party has conclusively proved its exercise of sovereignty over the temple area—is the interpretation 'of Article 1 of the Treaty of 13 February 1904 between France and Thailand; [p 74]

(2) this interpretation follows from the determination of the watershed between the two river basins which is specified to be the frontier between Cambodia and Thailand in the Dangrek region;

(3) the technical evidence supplied by Thailand, largely contributed to by Cambodia's cross-examination, is by its precision and abundance conclusive in establishing that the watershed follows the edge of the cliff of the promontory on which the temple is situated;

(4) this result decides the case in the sense that the portion of territory on which the temple stands is situated in Thai territory.

(Signed) Lucio M. Moreno Quintana.

[p 75]
DISSENTING OPINION OF JUDGE WELLINGTON KOO

To my great regret I am unable to concur in the Judgment of the Court. Although I reserve my own final conclusion in the case for reasons explained toward the end of this statement, I find that the grounds upon which the Judgment is based cannot be sustained in fact or in law.

1. The basic issue of the dispute, as it appears clear from the final submissions of the Parties as well as from their respective pleadings, both written and oral, is the question whether the Temple of Preah Vihear is situated in territory under the sovereignty of Cambodia or under that of Thailand.

2. Cambodia relies on the map of the Dangrek sector (Annex I to the Memorial); and contends that it "was drawn up and published in the name and on behalf of the Mixed Delimitation Commission set up by the Treaty of 13 February 1904, that it sets forth the decisions taken by the said Commission and that, by reason of that fact and also of the subsequent agreements and behaviour of the Parties, it presents a treaty character". She further claims that "the frontier line between Cambodia and Thailand, in the disputed region in the vicinity of the Temple of Preah Vihear, is that which is marked on the map of the Commission of Delimitation between Indo-China and Siam" and that "the Temple of Preah Vihear is situated in territory under the sovereignty of the Kingdom of Cambodia".

3. Thailand denies any validity to the claims of Cambodia and argues, principally, that "the map Annex I has not been proven to be a document binding on the Parties whether by virtue of the Treaty of 1904 or otherwise"; that "Thailand and Cambodia have not in fact treated the frontier marked out on Annex I as the frontier between Thailand and Cambodia in the Dangrek region"; and that "for the above reasons, the frontier line marked on Annex I ought not to be substituted for the existing boundary line in fact observed and accepted by the two Parties in the Dangrek range". She further contends "that at all material times Thailand has exercised full sovereignty in the area of the Temple to the exclusion of Cambodia" and that "if, which is denied, Cambodia in any sense carried out any administrative functions in the said area, such acts were sporadic and inconclusive, and in no sense such as to negative or qualify the full exercise of sovereignty in the said area by Thailand". [p 76]

I

4. Does the Annex I map possess, as claimed by Cambodia, a treaty character and therefore impose a binding obligation on Thailand? To give a correct answer to this question, it is necessary first of all to examine closely what evidence has been produced before the Court by both Parties. A careful perusal of the relevant documents, however, reveals nothing to show or even suggest that any discussion of the boundary line marked on Annex I map took place in the Mixed Commission of Delimitation or that any decision was taken by it. Twenty-five Minutes of the said Commission have been filed with the Court and they contain no record of any such discussion or decision. Yet it will be recalled that at the very first meeting of the said Commission on 31 January 1905 held at Svai Don Keo, a French and a Siamese secretary were respectively appointed by the two Presidents to draw up minutes of the meetings, and it was agreed by them that "the task the Commission had to fulfil was therefore divided into three parts:

1. The reconnoitring of the territory.
2. Surveying the territory.
3. Discussion and definite fixing of the frontier."

5. At the meeting of the Commission on 7 February 1905, when a difference of opinion arose as to the best way of determining the frontier line with reference to the sources of the Prek Kompong Prak and the watershed between the Stung Pursat and the river Mong, Commandant Bernard, the French President, reminded General Mom Chatidej Udom, the Siamese President, of the procedure established at the first meeting, according to which:

"the Commission should first carry out a general reconnoitring, gather information of various kinds which would make it possible to fix on the spot the points through which the frontier passed, then mark that frontier on the map and finally, if necessary, discuss whether it was correct and make any essential modifications. As soon as agreement was reached, the frontier line would have been finally determined by the members of the two Commissions signing the map on which the frontier had been marked."

As another example of the importance which the Mixed Commission attached to the agreed procedure of delimitation, as stated above— and there are many others in the Minutes of its meetings—I may refer to the discussions between the two Chairmen at a meeting of the said Commission on 18 January 1907 at Pak-Moun relating to the Siamese proposal to take as frontier the central meridian falling between the O Roun and the former bed of the Prek Kompong Tiam, when Colonel Bernard replied:[p 77]

"The question could not be studied until the two Commissions were in possession of the maps which were then in course of preparation and which the topographical officers were to take with them to Bangkok."

6. Since it has not been claimed that other meetings of the Mixed Commission had been held, the Minutes of which had been lost, it can be concluded that no other meeting had taken place and that no decision concerning the frontier line of the Dangrek sector to the east of Kel Pass and west of the Pnom Padang as marked on the map Annex I, according to which the Temple of Preah Vihear is situated within Cambodian territory, had ever been taken.

7. It appears equally clear from the agreed procedure of the Mixed Commission for its work of delimitation that the French officers who were charged with the making of the maps, including the Annex I map, had no authority to give any final interpretation about any part of the proposed boundary line including the line marked on the said map, in regard to which no decision had been taken by the Mixed Commission. Nor could it be maintained, in the absence of any evidence of specific instructions from the said Commission, that whatever power of adaptation which the Treaty of 1904 may have conferred on this Commission as a body, also appertained to the French topographic and geodetic officers whether for the Dangrek sector or for any other part of the frontier to be delimited.
8. The meeting of 18 January 1907 to which I have just referred was in fact the last meeting FN1 of the Mixed Commission which dealt with any question connected with the work of delimiting the frontier line stipulated in the Treaty of 1904. At this meeting the only decision taken was one which, in regard to "the determination of the frontier in the region of Pnom Pa Dang (Phu Pha Dang)" fixed the thalweg of the Huei Don as the boundary from where this stream meets the Mekong and stated: "The frontier would go up that thalweg as far as the source of the water course and would then follow the crest of the Phu Pha Dang to the south-west." This decision was also alluded to in Colonel Bernard's letter of 20 February 1907 to the French Minister in Siam:
---------------------------------------------------------------------------------------------------------------------FN1 There was another meeting of the Mixed Commission on 19 January 1907, but it was held solely for the purpose of determining "the plots of land that are to be conceded to the French Government at the mouth of the Semoun, in conformity with Article S of the Treaty of 13 February 1904".
---------------------------------------------------------------------------------------------------------------------

"All along the Dang Rek and as far as the Mekong, the fixing of the frontier could not have involved any difficulty. It was only a question of determining at what point Pnom Padang adjoins the Mekong. On this point there was no possible discussion for the mountain joins the river at one point about seven kilometres below Paknam." [p 78]

Here in the passage quoted above, Colonel Bernard, besides reporting the determination by agreement of the said point, was obviously expressing his own view as to the task of fixing the boundary all along the Dangrek. For on 20 February 1907 the report of Captain Oum, who had been assigned the work of surveying this sector of the Dangrek, had not yet been received, since we learn from Colonel Bernard's report of 6 March 1907 to the Governor-General of Indo-China that "the topographical officers arrived here between 18 February and 4 March and the provisional maps of the frontier region could not be completed until yesterday". "Here" evidently meant Bangkok and "yesterday" 5 March 1907. It is, therefore, clear that the Mixed Commission could not possibly have had a discussion, not to say taken a decision, at its meeting of 18 January 1907 to fix the boundary line all along the Dangrek westward from the Mekong to Kel Pass.

9. Another plenary meeting of the Mixed Commission, had, indeed, been contemplated, as it was reported in the letter of 23 February 1907 of the French Minister in Bangkok to the French Minister for Foreign x\ffairs:

"The maps indicating the frontier can be brought up to date in a fairly short time and the plenary meeting of French and Siamese Commissioners willl probably be held before 15 March."

Colonel Bernard himself considered that "the Delimitation Commission could not be dissolved without having closed the work by a final agreement" and used this point as one of his reasons for urging Mr. Strobel, General Adviser of the Siamese Government, whom he had already seen several times since his arrival in Bangkok on 1 March 1907, to push a French proposal, based upon his "more ambitious plan" of acquiring for French Indo-China the three provinces of Battambang, Siem Reap and Sisophon from Siam. According to Colonel Bernard's Report to the Governor-General of Indo-China of 19 March 1907, a plenary meeting of the Mixed Commission "which was to have taken place the next day, 8 March, was postponed indefinitely"—Annex 50 to Rejoinder. The French Minister in Bangkok, in his letter of 27 March 1907 to the French Minister for Foreign Affairs, states that:

"the delay that occurred with regard to the plenary meeting of the Commission was properly explained by the fact that topographical officers had not yet returned to Bangkok and no definitive map could therefore be submitted for the deliberations of its Members".

10. The same letter of the French Minister adds:

"On 8 March the first steps were taken and the conversations continued actively for six days. Mr. Strobel ... was definitely won over by the prospect of an arrangement of which he perceived all the advantages in the interest of both countries..." [p 79]

From 8 March on, a rapid succession of events followed. Colonel Bernard was in daily conferences with Mr. Strobel. In the evening of 13 March, the King of Siam, accompanied by his Ministers, met Mr. Strobel at the latter's residence for three hours and finally "authorized Mr. Strobel to proceed to written negotiations and recommended to expedite matters". A draft treaty was drawn up on 14 March and formed the basis of the negotiations. The final text of the Treaty of 1907 was prepared on 19 March. The treaty with its protocols and agreements was signed at 10 p.m. on 23 March 1907 by the Siamese Foreign Minister and the French Minister in Bangkok. Colonel Bernard left the Siamese capital on the 26th for Saigon from which he sailed for France on 5 April without holding a final meeting of the Mixed Commission to close its work he had contemplated.

11. I have given the above brief account of the busy events which fully occupied the time and attention of Colonel Bernard, who was also second French plenipotentiary to negotiate the Treaty of 1907, in order to indicate the circumstances which led to the indefinite postponement of the contemplated plenary meeting of the Mixed Commission of Delimitation. It was at this proposed meeting that, among other questions, the sketch map of a frontier line in the Dangrek sector from the foot of Pnom Padang westward to Kel Pass, drawn up by Captain Oum (a Cambodian officer and member of the French Commission, who, according to Colonel Bernard, "could not see these ancient glories of his country without writing or bringing him his complaints") was to have been discussed and decided upon, but actually no such meeting took place. In fact the work of delimitation of the First Mixed Commission was left unfinished.

12. It is true that, as a result of the meeting of the Mixed Commission of 2 December 1906 the Presidents of its French and Siamese groups made a journey together along the Dangrek range and probably visited the Temple of Preah Vihear. But there is no substantial reason to suppose that they took any decisions as to the frontier line in the Dangrek sector or as to the attribution of the Temple. It will be recalled that they, following an agreement reached at the said meeting of the Commission, travelled eastwards along the range from Kel Pass by the same route which Captain Tixier had reconnoitred in February 1905, and which was 10-15 kilometres from the crest of the Dangrek, on the Siamese side. The purpose of the journey had been explained by Colonel Bernard, the French President, when he had said that:
"from that road to the crest of the mountains, they would be able to make all the reconnaissances that might be thought necessary since they would be some ten to fifteen kilometres at most from that range". [p 80]

The surveying of the crest was yet to be undertaken by Captain Oum who had just been assigned the task. These two Presidents may have inspected the general topography of the sector and made all the necessary "reconnaissances" from distance but could not possibly have fixed any precise line, indispensable to a delimited frontier, without a complete report with sketch maps of the work of the survey officer and it would have been equally impossible to attribute the Temple to one Party or the other without knowing first where the finally delimited frontier line would be located in the sector.

13. Under Clause III of the Protocol attached to the Treaty of 1907 the second Mixed Commission of Delimitation set up under its Article IV "shall determine and trace if necessary, on the spot, that portion of the frontier which is described in Clause I of the present Protocol". In other words, it had the power and the duty, in case of need, to delimit any part of the portion defined in the latter provision, referring, obviously, to any portion which had not been delimited or the delimitation of which had only been partially done. But the second Mixed Commission did not avail itself of this power as regards the work of the first Commission. Could this fact be logically or reliably considered as showing that the first Mixed Commission must have completed its task including the final delimitation of the frontier in the whole Dangrek sector ? From what has been pointed out earlier, the only decision taken at the meeting of the first Mixed Commission on 18 January 1907 related to the fixing of the eastern terminal point of the frontier line connecting with the Mekong and the adoption of a line westward as far as the sources of the Huei Don and, following the crest of the Pnom Pa-dang, to the foot of this mountain range. This portion approximates less than 15 kilometres of a frontier line of some 300 kilometres long to be delimited from the said point westward to Kel Pass in the Dangrek sector. The failure of the second Mixed Commission to complete the unfinished work of the preceding Commission, though it had the power to do it, was obviously due to a misapprehension of the nature of the line adopted by the first Commission on 18 January 1907 as mentioned at the end of the penultimate paragraph of Clause I of the Protocol attached to the Treaty of 1907—a misapprehension which is explained in the following paragraph 16.

14. It is thus seen that the frontier line marked on the Annex I map was neither approved nor even discussed by the Mixed Commission of Delimitation nor was it agreed to by the French and Siamese Presidents of the said Commission. It follows from these indisputable facts that the map in question does not possess a treaty character as claimed by Cambodia and therefore, as such, obviously cannot be binding upon Thailand in regard to the issue of territorial sovereignty over the Temple of Preah Vihear.[p 81]

15. It is contended that even if the line on the Annex I map had not been approved by the First Mixed Commission, the Siamese Government had requested the French Commission to make this map as well as the other ten, and therefore the said map, though prepared in Paris by French officers under the supervision of the President of the French Commission of Delimitation, carried the consent and authority of Siam. But what is the nature of the request, and what is the real character of the map requested of the French Commission? The answer to these questions is clearly indicated in the Minutes of the meeting of the Mixed Commission of 29 November 1905. Commandant Bernard stated at this meeting:

"that he wished, before the Commission started work, to thank the Siamese Government for the proof of confidence it had just given the French Commission by requesting that the map of the whole frontier region should be executed by the French officers".

General Mom Chatidej Udom said in reply:

"that by leaving it to the French Commission to draw up the map of the frontier region, the Siamese Government had indeed wished to show that it had complete confidence in the French officers".

It appears that the requested map was a separate matter not directly connected with the work of delimitation of the Mixed Commission, and, as such, when it was made, certainly it could not be regarded as constituting or implying any binding obligation on Thailand as to the character of the map to be made. The correctness of this view of the nature of the request is borne out by the Minutes of the meeting of the Mixed Commission on 17 January 1906 at which Commandant Bernard, in discussing the programme of work for the French officers and the possibility for them to push on with the triangulation as far as the Dangrek so as to join up that year's work with the work of the following year, stated:

"If not, Captain Tixier and Lieutenant See would be employed in extending the surveys carried out by Captain de Batz and Lieutenant Tournyol so as to give a more complete map of the frontier region. At that moment there was no satisfactory map in existence and it would be useful for the two countries to have."

Clearly, this was to be a general map of the whole frontier region and did not form a part of the regular programme of delimitation of the Mixed Commission. Those portions of this map which contained frontier lines the determination of which was within the competence of the Commission and which were approved by it, of course possess a treaty or conventional character, not from the fact of a request by the Siamese Government, but from the fact of their approval by the said Commission, and the other portions [p 82] showing frontier lines, though also within its competence but not yet approved by it, such as map Annex I, cannot have this character.

As to the reference to "the Siamese Commissioners' request that the French Commissioners prepare maps of various frontiers" made in the letter of the Siamese Minister in Paris of 20 August 1908 to the Minister of Foreign Affairs in Bangkok transmitting the maps he had received from Captain Tixier of the French Commission, I do not attach particular importance to it. For it is not known what was the source of his information. There is no evidence of any of the Siamese Commissioners having communicated with him about their work or about the maps in question. Nor does it appear that his letter was in reply to any communication from his Government. More probably he simply repeated what Captain Tixier had presumably told him, verbally but imprecisely, while handing him fifty copies of the eleven maps including the Annex I map for forwarding to the Siamese Government, on the basis of the fact that the request of the Siamese Government for the French officers to prepare a general map of the whole frontier region had formed the subject of an exchange of friendly remarks between the Presidents of the two national Commissions at the meeting of the Mixed Commission mentioned above.

Consequently, the argument for the validity of the Annex I map based upon the request of the Siamese Government or even upon a request of the Siamese Commissioners, if true, to the French officers to prepare a general map of the whole frontier region between Siam and French Indo-China does not appear well-founded.

16. Nor, in my view, does the contention that the Protocol annexed to the Treaty of 23 March 1907 was a confirmation of the Annex I map have more substance. Clause I of this Protocol, after describing the greater part of the new frontier between French Indo-China and Siam as the result of the mutual cessions of territory stipulated in the 1907 Treaty, states that:

"it continues in a straight line to a point situated on the Dang-Rek, half way between the passes called Chong-Ta-Koh and Chong-Sa-Met",

and then it reads in its third paragraph:

"From the above-mentioned point situated on the crest of the Dang-Rek, the frontier follows the watershed between the basin of the Great Lake and the Mekong on the one side, and the basin of the Nam-Moun on the other, and reaches the Mekong downstream of Pak-Moun, at the mouth of the Huei-Doue, in conformity with the line adopted by the preceding Commission of Delimitation on the 18th January, 1907." [p 83]

What had been decided on 18 January 1907 was to fix the eastern terminal point of the proposed frontier line which meets the Mekong in pursuance of the relevant provision of the Treaty of 1904 and to approve a small portion of the frontier line therefrom as far as the source of the Huei-Doue (Huei Don) and the end of the crest of the Pnom Padang (Phu Pha Dang). This delimited portion was shown in a rough sketch attached to Colonel Bernard's letter to the Gover-nor-General of Indo-China of the same date as the said meeting of the Commission. No sketch map covering the whole line along the Dangrek from the Mekong west to Kel Pass had been brought back by Captain Oum as yet. He was then on his way west to Bangkok and was not due there until after 20 February 1907, and the sketch map was not completed till 5 March 1907. The Mixed Commission could not have had this sketch at its meeting of 18 January 1907. The only line which could have been and was "adopted by the preceding Commission of Delimitation on the 18th January, 1907" was the one shown in the sketch enclosed in Colonel Bernard's letter just mentioned. I have already referred earlier to an apparently similar misapprehension on the part of the Second Mixed Commission of Delimitation set up under the 1907 Treaty of the character of the line adopted by the first Mixed Commission at its meeting on 18 January 1907. In no way can the said protocol be validly said to have the effect of confirming the whole frontier line in the Dangrek range east of Kel Pass as marked on the Annex I map.

II

17. In the face of the established fact that neither the line shown on the Annex I map nor a sketch of it was ever approved or seen by the first or second Mixed Commission of Delimitation at any of its meetings, the Judgment of the Court seeks to infer an alleged acceptance of the said map by Siam from certain circumstances.

18. One of these circumstances is that after the eleven maps of the different sectors of the frontier, including the Annex I map, were prepared and printed in Paris under the supervision of Colonel Bernard in 1908 and fifty copies of each were delivered by Captain Tixier, a French member of the Mixed Commission of Delimitation, to the Siamese Legation in Paris for transmission to the Siamese Government, the Siamese Minister in Paris, after retaining two copies each for the use of his Legation and distributing one copy each to the Siamese Legations in London, Berlin, Russia and America, forwarded the rest to his Government in Bangkok which received them without raising an objection, or making a reservation, to the frontier line marked on the Annex I map. It is also emphasized that Prince Damrong, the Siamese Minister of the Interior, thanked [p 84] the French Minister for sending him an extra set and even asked for fifteen more sets for the purpose of distributing them among the Siamese provincial authorities.

19. The essence of the argument under consideration is that the Siamese authorities mentioned in the preceding paragraph must, upon receiving it, have seen the line mapped and noticed the loca-tion of the Temple of Preah Vihear on the Cambodian side, yet they did not raise any objection. It is quite probable that the said Siamese authorities did look at the map but it does not necessarily follow that therefore they must have discovered the actual location of the Temple. The said map is one of a set of eleven, and there was no special reason why the Annex I map should have been singled out at the time for particular attention. No question about the Temple had been raised by either France or Siam during the negotiations for the Treaty of 1904 or subsequently in the meetings of the Mixed Commission of Delimitation. It had never been in issue between the two Parties at.any time before 1908. Moreover, the Annex I map was drawn on the scale of 1 : 200,000, which means that the distance of 500 metres on the ground lying between the alleged frontier line and the Temple area is represented on the map by a width of only 2.5 millimetres. And because the Temple is perched on the summit of the promontory of Preah Vihear, the mark indicating the Temple is buried in a tangle of contour lines in a small part of the map. Even if one looks specially for the mark, it is by no means easy to find it. The alleged reason, far from constituting a legal basis for the presumption of Siam's acceptance of the Annex I map, is no more than a conjecture.

20. It was certainly not unusual for Prince Damrong to have expressed his appreciation upon receiving an extra copy of the whole series from the French Minister who obviously did it as a special act of courtesy. Nor is it difficult to understand that he should have requested more copies for distribution to the Siamese provincial authorities, especially when it is recalled that at the time Siam did not yet have a good modern map showing the whole frontier region between Siam and French Indo-China, and that the Siamese Government had previously requested the President of the French Commission to have one made by the French topographical officers. In the light of these facts the Prince's expression of appreciation to the French Minister and his request for more copies, in my view, have no special significance and cannot reasonably be considered to support a legal presumption of Siam's acceptance of the boundary line marked on map Annex I.

21. Under an authorization of the French Minister of the Colonies dated 26 May 1908, Captain Tixier undertook to allocate the series [p 85] of II maps including the Annex I map. To the "Members of the two Commissions" he sent 19 copies, so the Siamese members of the first Mixed Commission of Delimitation obviously also received their share of the copies. But this fact, in my view, does not bear the special significance attributed to it. The said Commission had ceased to function for more than a year, and its unfinished work had been taken over by the second Mixed Commission set up under the Treaty of 1907, so that the Siamese members of the preceding Commission had no longer any official capacity as such. They may or may not have examined the maps they received, but they certainly had no obligation to verify the accuracy or inaccuracy of the maps. Whatever may have been their reaction or attitude, their silence or neglect could not justly be considered to entail responsibility upon the Siamese Government as evidence of its tacit acceptance of the Annex I map.

22. A "Franco-Siamese Commission for the Transcription of the Map of the Frontier" was organized in 1909 and held two meetings to carry out its task. The two Siamese members, while they performed their part of the common duties, said nothing about the Annex I map. Could their silence on these occasions be validly considered to have a significant bearing upon the principal issue in the present case? According to the minutes of this body, the first meeting was held on 25 March 1909 and "the purpose of the Commission" was stated by Commandant Luang Bhuwanart Narubal of Siam to be:

"To try to find a system of transcription for adoption by the two countries in order to obviate any misunderstanding arising from the perusal of maps in which the names were erroneous or badly spelt. With that object, he had drawn rules for the transcription of Siamese characters in Roman characters and vice versa. He then submitted his work to the French Commission and the latter approved it after making a few modifications." (Annex XLVIII (c) to Cambodian Reply.)

The second meeting took place on 4 October 1909 and it is recorded in its minutes:

"The purpose of the meeting was to determine the main lines for the production of the general map. In the Protocol signed in Bangkok on May 1908, following on the operations of the Commissions for the delimitation of the frontier between Indo-China and Siam, one of the clauses stated that a general map of the new frontier would be drawn up jointly by French officers and Siamese officers." (Annex XLVIII (d) to Cambodian Reply.)

The text of the said Protocol has not been produced, but the nature of the work of the Transcription Commission is clearly indicated in the minutes: [p 86]

"The object in view was to make available to officials of the two nations a document of identical nature, as detailed as the scale agreed upon would permit, which should do away with the errors in names that were so frequent, particularly when a frontier incident occurred...

The division into sheets as shown on the attached assembly table, showed that, by producing the maps which are surrounded by a red line, the whole of the abovementioned frontier zone would be covered by fifteen sheets and three half-sheets.

The format adopted would give a height of 250 millimetres and a width of 400 millimetres excluding borders and margins, so that each sheet would represent a portion of territory measuring 125 kilometres X 200 kilometres." (Ibid.)

It is thus seen from the above-quoted passages that the work of the Commission, both as regards the transcription between Siamese and Roman characters on the maps and as regards the production of a general map, was entirely of a technical character to be carried out jointly by the French and Siamese members, who were apparently all experts in the field of cartography. They were not called upon by their terms of reference to verify the accuracy or inaccuracy of the frontier line marked on any of the maps they used in their work nor did they have any good reason to take up the task of verification on their own initiative. Consequently, the silence of the Siamese members of the Transcription Commission as to the line on the Annex I map in no way constitutes a substantial reason to support the contention of Siam's tacit acceptance of the said line.

23. In 1934-1935, as the result of a survey by her own officers, Siam discovered for the first time the erroneous location of the Temple of Preah Vihear on the Cambodian side of the frontier line as marked on the Annex I map. On the basis of this fact it is argued that since she raised no question about the error until 1958, she must be presumed to have accepted the Annex I map as correct. It is, however, to be recalled that as soon as the relative position of Siam vis-á-vis French Indo-China became less unbalanced as a result of the development of world events in 1940, the Siamese Government posted a Siamese guardian at the Temple to signify Siam's title of sovereignty over the area. When in 1953 Cambodia dispatched three guardians of its own to watch the Temple, they were sent back by the Thai (Siamese) authorities. When in 1954 the Cambodian Minister in Bangkok notified the Thai Minister for Foreign Affairs of his Government's intention to dispatch a detachment of troops to take possession of the Temple, Thailand at once sent a unit of its armed frontier police to the area in order to forestall the contemplated action of the Cambodian Government. These positive acts clearly evidence the absence of any intention on the part of Siam or Thailand to acquiesce in or accept the said [p 87]
map line.

24. Importance is also attached to the Treaties of 14 February 1925 and 7 December 1937 and the Settlement Agreement of 17 November 1946 as further confirmation of the frontier line in the Dangrek shown on the Annex I map. But an examination of the relevant provisions of these instruments fails to bear out the assertion. Article 2 of the 1925 Treaty states:

"The High Contracting Parties confirm and reciprocally guarantee to respect the frontiers established between their territories by virtue of and in conformity with the provisions of former agreements and maintained by Article 27 of the present Treaty";

and the relevant portion of this Article 27 reads:

"It shall also annul as from the same date the other treaties, conventions and agreements concluded between France and Siam with the exception, however, of the clauses regarding the definition and delimitation of the frontiers (contained in the Treaty of October 3, 1893, the Convention of February 13, 1904, the Treaty of March 23, 1907 and the Protocol annex thereto) ..."

Again, Article 22 of the 1937 Treaty states:

"The present Treaty shall, as from the date of its entry into force, replace the Treaty of Friendship, Commerce and Navigation concluded at Bangkok on February 14th, 1925. It shall also annul, as from the same date, the other Treaties, Conventions and Agreements concluded between Siam and France, with the exception, ' however, of the clauses relating to the definition and demilitation of the frontiers, the guarantee in respect thereof, and the demilitarization of the Mekong frontier (contained in the Treaty of October 3rd, 1893, the Convention of February 13th, 1904, the Treaty of March 23rd, 1907 and the Protocol annexed thereto, and the Treaty of February 14th, 1925) ..."

It can be seen from the foregoing provisions that the confirmation is of a general character, and refers to the whole body of territorial settlements determined by the previous treaties still in force. Nothing is said therein about the particular frontier line in the Dangrek marked on the Annex I map. Indeed, the question of this confirmation appears clearly to have been only an incidental one because the main subjects of negotiation related to quite different subjects, as the titles of both instruments indicate, namely, Treaties of "Friendship, Commerce and Navigation between Siam and France".

25. It is argued that if Siam had considered the Temple of Preah Vihear to have been incorrectly placed on the Cambodian side of the frontier line shown on the map Annex I, she should have made a reservation to that effect in the Treaties of 1925 and 1937, the Settlement Agreement of 1946 and the Report of the Commission in 1947, because all these instruments confirmed or restored the [p 88] territorial settlements stipulated in the earlier Treaties, including the Treaty of 1904 and the frontier lines delimited by the Mixed Commission set up under the said Treaty; and that her failure to do so must be regarded as evidence of her tacit acceptance of the frontier line on the Annex I map.

26. As has been pointed out earlier, the said confirmation is entirely of a general and incidental character. The two Treaties of 1925 and 1937 deal principally and almost exclusively with the questions of "Friendship, Commerce and Navigation between Siam and France". Of the 29 Articles and 2 Protocols of the Treaty of 1925, only Articles 2 and 27 relate to the confirmation of the definition and delimitation of the frontiers provided for in the former Treaties. The Treaty of 1937 contains 24 Articles, 1 Protocol and 6 Exchanges of Notes, but only one of them, Article 22, provides for the said confirmation. These two occasions could hardly be regarded as appropriate for making a reservation as to the question of sovereignty over the Temple area. There is no evidence to show that in 1925 Siam had already found out that the Temple was incorrectly located, and, even assuming it had, it would still appear reasonable to ask whether the occasion, such as it was, was one which would normally have called for or justified a reservation of the character stated. By 1937 Siam's own survey department had, in 1934-1935, as already noted, discovered the mistake as regards the location of the Temple on the Annex I map, but the circum-stance in which the Treaty of 1937 was negotiated was not so different from that of the 1925 Treaty as to warrant a reservation.

27. Moreover, the two bilateral instruments referred to above could not have been intended, and certainly they do not stipulate, to cure any inherent defect in any of the previous Treaties, proto-cols annexed to them, and agreements relating to territorial settlements and delimitations of boundary lines. This observation applies even with greater force to a document unattached to any of the said instruments such as the map Annex I. By their general language they simply confirm these instruments as they stand with their perfections and imperfections; they detract nothing from their contents nor add anything to them. The fact that the Annex I map was not approved by the Mixed Commission of Delimitation set up under the Treaty of 1904 still stands as a pertinent fact, and its lack of a treaty character remains true today.

28. The Settlement Agreement of 1946 was negotiated and concluded at the request of France for the purpose of restoring the status quo ante in regard to the whole boundary line between French Indo-China and Siam prior to the Convention of Tokio of 9 May 1941. In fact it provided for the abrogation of the said convention and for the restoration in toto of the territorial settle-ments confirmed in the Treaties of 1925 and 1937. If this act of restoration is to be regarded as an act of confirmation of the terri-[p 89]torial settlements effected by the Treaty of 1904, it certainly amounts to no more than what is confirmed by the Treaties o" 1925 and 1937.

29. The Report of the Conciliation Commission was issued i 1947 after Siam and France had respectively argued for and again: certain territorial changes proposed by the former, the Siame claim aiming to recover certain whole provinces from France. It would have been out of place for the Siamese Government to raise, on that occasion, the question of sovereignty over the small piece of territory as the Temple area, the more so, since this question was not in issue at the time. Moreover, the Temple continued to be watched by a Siamese guardian since 1940. In view of this fact, it would seem to have been more appropriate for France to make a reservation or protest at the time, but none was made either.

30. The fact that the Siamese Royal Survey Department produced a map in 1937 showing Preah Vihear as lying in Cambodia is, in my view, of no significance as regards the question of Thai-land's attitude to the Annex I map. As explained by Counsel for Thailand, it was intended for use by the Siamese military authorities. It is nothing unusual that in the privacy of a country's own survey department maps of any kind, of whatever origin, should have been reproduced for its own use either for their scale and useful details or for other reasons.

31. Thailand's use of a map before the Franco-Siamese Commission of Conciliation in 1947, in which the Temple of Preah Vihear is located on the Cambodian side, may appear striking at first sight. But it has no more significance than the map of 1937 just considered, when the circumstances in which it was used are taken into account. As has been stated earlier, Thailand's case before the Commission consisted of claims the chief of which was for retrocession from France of several entire provinces which she had reluctantly yielded to her mainly in 1904-1907, and the map was obviously used to indicate their location and limits. The question of the Temple of Preah Vihear was not in issue, since to raise this question at the time, involving the territorial sovereignty of an area of the size covered by the ruins of this sanctuary along with Thailand's principal claim for the retrocession of several provinces would obviously have appeared incongruous and out of place. The occasion, as has been noted earlier, was clearly not a compelling or appropriate one for this purpose.

32. The incident of a visit of Prince Damrong to the Temple of Preah Vihear in January 1930 and the presence of the French Resident of the neighbouring Cambodian province of Kompong Thom on the scene in his official uniform with decorations and the appearance of the French flag on a pole in front of his own pavilion [p 90] is regarded as particularly significant. But the facts are simple and do not support the claim of significance assigned to it. The Prince then was no longer Minister of the Interior; he was President of the Royal Institute of Siam with duties connected with the National Library and archaeology. He made the trip to Preah Vihear in the latter capacity, accompanied by his three daughters and a suite of officials. The French Resident had with him his assistant and the noted French archaeologist Henri Parmentier. When the parties met on the Temple grounds, speeches of welcome and thanks were exchanged and toasts were drunk. The Resident said he had come to present the compliments of the Superior Resident and his own to the Prince for his "reputation as a sincere friend of France and her subjects and proteges" and also as a well-known archaeologist. No allusion was made by the French Resident to any ques-tion about the territorial sovereignty over the Temple, though Parmentier, speaking as a fellow archaeologist and extolling the fame of the Prince for his interest in archaeology, referred to the Temple as "another of the monuments of our Cambodia" (Annex LIII b to Cambodian Reply). The Prince, in his reply, said that "he had come to see the Temple and had nothing to do with politics".

33. According to a statement of his daughter who accompanied him on the visit, he suggested to the French officer "to get out of his uniform". The display of his national flag by a foreign official, even by a private Occidental, was not an uncommon sight in an Asiatic country during that epoch; it may or may not have displeased the Prince. There was no clear cause for the Prince to make a protest at the time or to ask his Government to lodge one in Bangkok, though in the affidavit of one of his daughters who was with the Prince during this visit, it is stated that he privately considered the hoisting of the French flag at the place of their meeting and the donning of his official uniform by the French officer to be "impudent". The despatch of a letter of thanks and some photographs taken during his visit by Prince Damrong to the French Minister for transmission to the French authorities in Indo-China meant no more than a customary act of Oriental courtesy. In a word, the incident viewed in the light of the available evidence and the then prevailing conditions in Siam—and, in fact, in other parts of Asia—did not have the meaning and significance sought to be inferred from it.

34. It is of course an undisputed fact that both the pavilion in which the French Resident and his associates spent the night and the flag pole on which was hoisted the French national flag had been put up specially for the temporary purpose of welcoming the Siamese Prince. In view of this fact, taken together with the other [p 91] related circumstances referred to above, it may be reasonable to presume that the French officer's presence had been intended to assert French authority or Cambodia's sovereignty over the Temple area and that the Prince or the Siamese Government must have regarded the episode in itself as constituting a sufficient cause for protest. However, even if this presumption is correct, it does not necessarily follow that they should not have waited for a more propitious occasion to make one than in the actual circumstances prevailing at the time. The reason why "he did not ask the Government to lodge a protest" was eloquently stated by his daughter, Princess Phun Phitsamai Diskul, who went with him during the visit to the Temple, to be as follows:

"It was generally known at the time that we only give the French an excuse to seize more territory by protesting. Things had been like that since they came into the river Chao Phya with their gunboats and their seizure of Chanthaburi."

In view of the history of the relations between Siam and French Indo-China at the time and earlier during the preceding decades, the Princess's explanation seems natural and reasonable. It was a situation not peculiar to Siam. It was, generally speaking, the common experience of most Asiatic States in their intercourse with the Occidental Powers during this period of colonial expansion.

35. Thailand's failure to reply to the four notes addressed by the French Legation in Bangkok to the Ministry of Foreign Affairs, at first enquiring about the presence of Thai guardians at the Temple of Preah Vihear, later stating that the ruins of this sanctuary were "indubitably situated in the territory of Cambodia", asking that measures should be taken to put an end to the situation, and setting out the French point of view as to the historical and legal aspects of the frontier question, is regarded as another ground for presuming Thailand's tacit acceptance of the boundary line marked on the map in question. What were the actual considerations which induced the Siamese Government to refrain from replying to the notes in question is not known. But whatever they were, whether it was because the French claim was clearly based on an error in relying on the Protocol attached to the Treaty of 1907 or it was because Siam had always regarded the Annex I map as of no binding character, or for any other reason, her consistent attitude and conduct during the five decades since 1904 in respect of her title to sovereignty over the Temple area are facts which clearly refute the presumption. Moreover, it will be recalled, as Prince Naradhip stated at the time of negotiations with the Cambodian plenipotentiaries in 1958, that the Thai guardians of the Temple had remained on post since 1940. This is a significant fact to be noted; it [p 92] indicates the true intention and attitude of Thailand in respect of the question of sovereignty over the Temple area.

III

36. Since Cambodia's claim of sovereignty over the area in which the Temple of Preah Vihear is situated is based upon an alleged treaty character of the Annex I map which shows its location of the Temple on the Cambodian side of the frontier line marked thereon, and since the said map has been shown to be devoid in this character, it is important to consider the comparative attitude and conduct of the two Parties as tending to throw light on their respective intentions in regard to the question of sovereignty over the Temple.

37. With reference to this point, Cambodia has produced a number of documents and photographs relating to the "administrative tours" of the Governor of Kompong Thom "to Preah Vihear" and to the visits of several foreign missions, accompanied by him, to the Temple. According to the dates stated therein, all these visits and tours took place during the term of office of Governor Suon Bonn who also testified at the hearing. In other words, it was from 1948 to 1953. The more important of the documents submitted include a decree of the Governor-General of Indo-China of 16 May 1925 relating to the classification of the historic monuments and including the Temple of Preah Vihear among them (Annex XII to Memorial), a report of Commandant Lunet de La-jonquiére in 1907-1908 on the ancient monuments, including the Temple of Preah Vihear, published in the Bulletin of the Archaeological Commission of Indo-China in 1909, in which he stated:

"The last delimitation of the frontiers attributes Preah Vihear, which is studied in that work under No. 398, to France." (Cambodia's Annex LXXXVI.)

38. Thailand, on her part, has filed with the Court a number of affidavits and copies of original documents as evidence of acts of administrative control by Siamese authorities in exercise of sov-ereignty in the area in which the Temple of Preah Vihear is situated. These acts relate, among other matters, to the building of roads to the foot of Mount Preah Vihear, the collection of taxes by Siamese revenue officers on the rice fields of Mount Preah Vihear, the grant of permits to cut timber in the area, the visits and inspections by Siamese forestry officers, the taking of an official inventory in 1931 of ancient monuments which included the Temple of Preah Vihear, the visit of the Under-Secretary of the Ministry of the Interior in 1924-1925 and the visit of Prince Damrong in 1930, both visits including the Temple of Preah Vihear. [p 93]

39. It is difficult to find substance in the argument which rejects Siam's positive acts of administrative control in the disputed area as evidence of conduct as sovereign for the alleged reason that these acts were performed by local or provincial authorities in contradiction with the consistent and undeviating attitude of the central Siamese authorities to the frontier line as mapped. This is an assumption refuted by the facts as shown. Moreover, administrative acts in the Mount Preah Vihear area, on which the Temple of the same name is situated, must necessarily have been performed by local officials as they were in other areas—acts such as collecting taxes, building roads, inspecting the forests, etc. They carried out these duties under the supervision of the Governor of Khukhan Province upon whom they depended for orders. The Governor himself was appointed by the King of Siam and was responsible to the Government in Bangkok. He not only had to submit periodic reports of his administration to the central government but also to carry out its instructions. The correspondence relating to the visit of the Deputy Minister of the Interior to his Province on an inspection tour in 1925 (Annexes 37 fl-37 i to Counter-Memorial) and a like visit of Prince Damrong in 1930 (Annexes 39 a, 39 b and 39 c to Counter-Memorial), both visits including the Temple of Preah Vihear, shows further that the central government was in close contact with the provincial authorities, who in turn kept in close touch with the local officials. The "report of H.R.H. Krom Phra Nakhonsawan Woraphinit to His Majesty the King" in 1926 on the results of his inspection tour of the provinces is particularly illuminating. There can be little doubt that the acts of administrative control performed by the local authorities in the Temple area, far from contradicting any attitude of acquiescence in the said frontier line, reflect and confirm the consistent belief of the central Siamese government that the said area was under the sovereignty of Siam. In this connection it is pertinent to quote a particularly significant passage in the report of His Royal Highness just mentioned:

"The Governor [of Khukhan] informed me that in the area of the District Office of South Sangkha within the frontier mountain there is a stone temple on five elevations which is very big and beautiful, called Phra Viharn. (In the French map it is called Preah Vihear.) This stone temple is within our territory." (Annex 22 to Counter-Memorial.)

40. The belief that the Temple of Preah Vihear is within Siamese territory has not been confined to the prince alone but entertained generally by the Siamese central and local authorities. It is well [p 94] supported by a series of relevant facts. Before "the last ratification of the Treaty [of 1904] with France" the Siamese Minister of the Interior "sent telegrams to the various Governors-General forwarding a draft Proclamation concerning the territories ceded to France with the advice that it is to be made ready for posting, upon ratification, for the information of the inhabitants". Upon ratification, he sent telegrams, dated 10 December 1904:

"advising that the Proclamation should be posted within 15 days from receipt of the telegrams and asking for confirmation of the dates on which the local authorities in the territories ceded to France shall have received the same, so that the French Government may be informed accordingly for the purpose of taking over such territories".

On 16 December 1904 he informed the Siamese Foreign Minister further that:

"a telegram has'been received from H.R.H. Sanphasit, His Majesty's High Commissioner for Isan, No. 19 dated the nth instant, that advice has been given with instructions to Champasak and Khukhan to forward the Proclamations to 14 districts where all official work should stop so that the work of handing over the territories to France may be attended to".

Khukhan is the province in which the Temple of Preah Vihear is situated.

41. From the passages quoted above, it appears certain that all the territory ceded to France under the Treaty of 1904 was handed over to the French authorities in due course and that the Mount Preah Vihear, on the top of which the Temple of the same name stands in ruins, and the immediate vicinity were not understood by either Party to be part of the ceded territory. For it is an un-controverted fact that the Siamese authorities continued to enforce administrative control over the area without any protest from the French authorities or any objection by the local inhabitants. This fact is significant, because the documentation shows that the French authorities had been alert and vigilant in having France's newly acquired territorial sovereignty respected by Siam. Thus, take one example out of many contained in the documentation to illustrate French alertness and vigilance. When five months after certain villages situated in the territory between the Pnom Padang and the Mekong had been handed over to the French authorities in January 1905, a Siamese official informed the local populations that the villages in question belonged to Siam and forbade them to obey the orders of the authorities of Bassac in Cambodia and later the same Siamese official sent agents to take a census of the inhabitants, animals and vehicles in those villages, the authorities of Bassac protested at once. The matter was reported to the Administrator of that province, the Resident Superior of [p 95] Laos and the Governor-General of Indo-China. The question was finally brought to the attention of the President of the Siamese Commission of Delimitation by the President of the French Commission. An investigation was made in due course, the complaints were found to be justified, and the Siamese President attributed the matter to "a mistake in the interpretation of the Treaty". Yet as regards the Temple area, though the Siamese local authorities continued to exercise administrative control after the Treaty of 1904 as they had done before, the French authorities did not protest at any time nor did the local inhabitants make any complaint, a course of action which they would certainly have taken if they had considered the Temple area to be part of the ceded territory.

42. Even though it might be said that the question of which Party was at the time entitled to the right of exercising sovereignty in the said area could not have been definitively settled until after the determination of a precise line of frontier by delimitation, the fact that, with the plausible exception of the episode of Prince Damrong's visit to the Temple of Preah Vihear in 1930, the French authorities did not at any time assert French authority or Cambodia's sovereignty, or raise any question or make any protest to Siam against continued performance of administrative acts in the Temple area until 1949 cannot be explained, except on the ground of their tacit recognition of Siam's sovereignty over the said area, or, presumably, on the ground of their knowledge that the frontier line on the Annex I map which had been drawn tentatively by Captain Oum, a Cambodian Member of the French Commission and an apparently ardent Cambodian irredentist FN1, had not been approved by the Franco-Siamese Mixed Commission of Delimitation to make it binding on Siam.
---------------------------------------------------------------------------------------------------------------------FN1 See Annex 58 to Rejoinder.
---------------------------------------------------------------------------------------------------------------------
43. Another important fact evidencing Siam's consistent belief in her title of sovereignty over the Temple area should be noted. In accordance with a Royal Proclamation of 17 January 1924, relating to the inspection and preservation of archaeological objects in Siam, Prince Damrong, President of the Royal Institute, addressed two communications to the Governor-General of Nakhon Ratchasima, respectively of 23 July 1930 and 22 July 1931, calling for a verified inventory of ancient monuments in the Monthon. On 31 August 1931, the said Governor-General sent a reply enclosing an inventory in which "Khao Phra Viharn [Temple of Preah Vihéar] constructed of stone with fourteen edifices, built on five elevations, some of which are rectangular in shape of various sizes" is clearly stated to be one of the four ancient monuments in Chang-wat Khukhan, one of the provinces under his jurisdiction. (Thailand's Annexes 78 a-78 b.) [p 96]

IV

44. The foregoing account of facts and circumstances summarizes the situation which underlies the present dispute between the Parties. To resolve the dispute by a presumption of Thailand's tacit acceptance of the Annex I map on the ground of her silence or failure to react on several enumerated occasions runs, in my view, counter to the established facts and to the real character of the circumstances alleged to be relevant. For the purpose of evaluating the legal significance of silence relating to a claim of sovereignty words and conduct are the recognized indices or criteria. In the present case I have examined the evidence and found no statement or declaration of any kind by Siam or Thailand which recognizes, or can be considered to recognize, Cambodia's title to sovereignty over the Temple area. As to conduct, far from implying any acceptance of the Annex I map, she has consistently indicated a belief on her part throughout the past decades that the area in question continues to belong to her own sovereignty.

45. Thailand's claim in the present case to sovereignty over the Temple involves no question of good faith on her part. International jurisprudence attributes importance to silence as a relevant factor in determining the intention of a party in regard to a claim of sovereignty only in the light of its unequivocal conduct and of the attendant circumstances. Thailand's exercise of sovereignty in the form of sustained administrative control in the Temple area bears witness to her true intention. The evidence adduced refutes the argument in support of a presumption of her tacit acceptance of Cambodia's title to sovereignty over the Temple area as marked on the Annex I map.

46. Moreover, there is no valid ground in law for holding Thailand accountable for acquiescence. The rule of Roman law that "he who keeps silent is held to consent if he must and can speak" is, in my view, not applicable because the several occasions which are alleged to have been such as to call for a protest or reservation by her have been shown earlier to be entirely of a different character. Silence or failure to react, even when it constitutes a relevant factor, cannot alone be considered as implying recognition or acceptance of the other party's claim of sovereignty. In the Anglo-Norwegian Fisheries case, this Court attached legal importance to "prolonged abstention" of the United Kingdom from protesting against the Norwegian system of delimiting territorial waters but only as one of the factors: "The notoriety of the facts, the general toleration of the internationl community, Great Britain's position in the North Sea, her own interest in the question, and her prolonged abstention would in any case warrant [p 97] Norway's enforcement of her system against the United Kingdom" (I.C.J. Reports 1951, p. 139). In the case under consideration, no evidence has been adduced of any declaration or act by Siam or Thailand pointing clearly to her intention to recognize or accept Cambodia's claim of sovereignty over the Temple area.

47. Nor is there substantial ground for application of the principle of preclusion. The legal basis of that principle is that one party has relied on the statement or conduct of the other either to its own detriment or to the other's advantage. In the present case Thailand has not made a statement at any time indicating her acceptance or recognition of the frontier line marked on the Annex I map. As regards the allegation of her silence as warranting the presumption of such acceptance or recognition, it is plainly contradicted by evidence of sustained State activity in exercise of sovereignty in the Temple area. There is no evidence to show that France, as Cambodia's protecting State, ever relied on Thailand's silence to her own detriment. Thailand's unequivocal conduct relating to the Temple area has continued to be the same after 1904-1908 as it had been before this period. France's own failure to make a protest or raise any question about it until 1949 appears to have confirmed Thailand's belief that the said area had always remained under Thai sovereignty under the Treaty of 1904. Nor could it be validly argued that "Thailand had derived special advantage from France's reliance, if there had been such, on her alleged silent acceptance of the Annex I map in 1908. In fact, as has just been shown, for over 40 years no such reliance appears to have been placed by France on the alleged binding character of the said map. What benefit Thailand may have received from the stability of the frontiers marked on the other ten maps, she has been entitled to it under the Treaty of 1904 and the delimitation work of the first Mixed Commission. These maps have not been put in question at any time. As regards the frontier of the Dangrek sector, if Thailand could be said to have enjoyed the advantage of stability, apart from her constant belief of the Temple area being always under her own sovereignty, it was due, not to any reliance by France upon Thailand's alleged acceptance of the Annex I map as binding on her, but rather to an apparent doubt on the part of the French authorities as to where the correct line really was with reference to the location of the Temple—a doubt which explains their continued silence and failure to raise any question in the face of the continued exercise of sovereignty by Thailand in the said area. In the light of the foregoing reasons, the application of the principle of preclusion against Thailand in the present case is, in my view, not justified. [p 98]

48. The usual object of a boundary treaty, of course, is to achieve certainty of the frontier to which it relates in accordance with the principle of stability, and the recognized procedure to attain this object is by joint delimitation on the ground. In the present case it was precisely this procedure which had been stipulated in Article 3 of the Treaty of 1904. Therefore, the argument which seeks to support the application of the principle of stability by setting aside the clear intention of the Parties, as expressed in the said Article providing for careful delimitation by a Mixed Commission, and by basing it upon the presumed consent of Siam to an undeli-mited line on the Annex I map, seems to me to be strained and unreal.

V

49. From the foregoing examination of the pertinent facts in this case and consideration of. the law applicable to it, I summarize my twofold conclusion as follows:

(1) that Cambodia has not succeeded in establishing the alleged binding character of the Annex I map; and

(2) that Cambodia's contention of Thailand's silence as tacit acceptance of the frontier line marked on the map Annex I is refuted by fact and not warranted in law.

50. Where is, then, the frontier line in the Dangrek with reference to the Temple area and on which side of this line, in Thailand or Cambodia, is the Temple of Preah Vihear situated ? The answer is provided, in principle, by Article 1 of the Treaty of 13 February 1904, which defines the frontier in the Dangrek as the ridge of "the watershed between the basins of the Nam Sen and the Mekong, on the one hand, and of the Nam Moun, on the other hand, and joins the Pnom Padang chain the crest of which it follows eastwards as far as the Mekong". Of course it goes without saying that what is pertinent of this frontier in the present case, as has been stated at the outset, is only that portion which relates to the area in which the Temple in question is situated.

51. The essential task, then, in order to decide the case, is to apply or interpret the 1904 Treaty. But where is the true location of the treaty-defined watershed? This is a crucial question, and a correct answer must be given. The two Parties in the case have submitted reports by their respective experts which purport to give the necessary answer. However, while the four reports, two from each side, agree on the general location of the watershed line in the disputed area, they disagree on the crucial precise line. The International Training Centre for Aerial Survey of Delft, Holland, on behalf of Thailand, presents a line which places the major part of [p 99] the Temple ground on the Thai side whereas Doeringsfeld, Amuedo and Ivey, "Specialists in Photogeology and Photo-interpretation", of Denver, Colorado, submit a line placing the main portion of the Temple on the Cambodian side. The conflicting character of the two expert recommendations presents a perplexing problem, and the difficulty has been further increased by the outcome of the examination and cross-examination of the experts and witnesses at the oral hearing. From their testimony, it appears that besides the I.T.C. line and the D.A.I, line, there are two other possible alternative lines: one at Point 3 near Letter F on Map Sheet 2 attached to Annex 49 of the Counter-Memorial, and another one from Contour Line point No. 605, which is just a little west of the D.A.I, line close to the western side of the Temple and which almost coincides with the latter line.

52. There is also the question of the nature of the terrain of the saddle near F, and its elevation, which, according to Thailand's expert, who went out to the Temple area and made an investigation on the spot, blocks the eastward flow of stream 3 on the Map Sheet 2 into the Cambodian plain and causes it to turn westward to join stream 2 flowing northward into Thai territory. Counsel for Cambodia casts doubts on the accuracy of this statement and, in support of his incredulity, he cites, among other works on archeaology, a passage from "L'Art Khmer classique" by Henri Parmentier, Chapter IV, in which this author records his study of the Temple of Preah Vihear on the spot in February 1930 and mentions "a rocky plateau" near the north-east corner of the Temple, which

"falls in a somewhat steeper slope towards the east where there is a rocky ravine, the water from which flows towards Cambodia, forming a fairly considerable stream, the O Kbal Pos Nakrac".

The divergence of these two views, moreover, raises the following questions: what is the altitude of the saddle near F? Is its elevation uniform throughout its surface? What is the character of its terrain? Does it bear any traces of change by the hand of man?

53. Since there is no available record of any sketch map drawn up by Captain Oum on the basis of the survey he carried out in the Dangrek sector east of Kel Pass in the period of December 1906 and January and February 1907—which was the dry season—showing a precise line of the watershed in the said sector, except what is claimed by Cambodia to have been marked on the Annex I map, whereas the I.T.C. line was verified on the spot during the wet season in July 1961, it is also pertinent to ask for the purpose of ascertaining the precise line: To what extent does the topography of the [p 100] stream channels in the Temple area vary between the dry and wet seasons of a normal year?

54. Furthermore, Cambodia has maintained that what is relevant in regard to the location of the watershed in the Temple area is where it was in the period of 1904-1908 and not where it is in 1961-1962. This point gives rise to other questions: could the location of a watershed change in the course of time by natural phenomenon such as an earthquake, faulting of rock-beds, landslide or rock fall, etc.? Or is the watershed now found by the experts of both Parties in the Temple area part of the same watershed which the negotiators of the 1904 Treaty had in mind or which Captain Oum presumably marked on his sketch map on the basis of his survey on the spot in the Dangrek sector?
55. All the foregoing questions are of a technical character and call for an independent expert or experts to supply reliable answers. I am of the opinion that the Court would have been well advised, under Articles 44 and 50 of the Statute, to send its own expert or experts to investigate on the spot and make a report of their observations and recommendations, as was done in the Corfu Channel case (I.C.J. Reports 1949). Such a report would have been of great assistance to the Court in deciding the case by law on the basis of all the relevant facts of a technical as well as other character. I for one feel unable to reach a final conclusion satisfactory to myself without knowing the answers to the technical questions which I have defined above and which, in my view, bear a vital importance for a correct determination of one of the crucial issues in the present case.

(Signed) Wellington Koo.

[p 101]
DISSENTING OPINION OF SIR PERCY SPENDER

I regret that I am not able to associate myself with the Judgment of the Court. The reasons which have led me to differ from the conclusion at which the Court has arrived should I think be stated.

In the nature of things different minds approach problems in different ways. The approach to a legal problem is no exception. What is to be solved will be solved according to the manner of him who solves it.

The present proceedings are burdened with a great volume of evidence, a considerable amount of which is quite irrelevant.

The task is to sift the wheat from the chaff.

The case, in my view, is peculiarly one in which a conclusion may safely be reached only by a detailed examination of the evidence and a strict application thereto of the relevant principles of international law.

My own examination has led me to the conclusion that Cambodia has failed to make out any claim for relief.

***
Article 40 of the Statute of the Court provides that the Application to the Court shall state the subject of the dispute. Article 32 (2) of the Rules of Court provides that it must also, as far as possible, state the precise nature of the claim and give an accurate statement of the facts and grounds on which the claim is based.

The subject of the dispute in this case is the Temple of Preah Vihear (in Siamese called Phra Viharn) over which the Kingdom of Cambodia claims sovereignty. Its claim as stated in the Application is based upon the terms of international conventions delimiting the frontier between it and Thailand.

The convention which the Application states is fundamental to the present dispute is the Treaty of 1904. This Treaty, supplemented by a protocol dated 29 June 1904, relates to a long line of frontier between Thailand and Indo-China. Article 1 thereof which dealt with a part of this frontier line stated, inter alia, that on the mountain chain of the Dangrek—on which the Temple happens to be situate—the frontier line should follow the line of the watershed until it reached a mountain range known as Pnom Padang, the crest of which it should follow towards the east as .far as the river Mekong. Article 3 stipulated that the delimitation of "the frontier [p 102] determined by Article 1" should be carried out by a Mixed Commission. Such a Commission was duly established.

Cambodia's contention, as stated in the Application and Memorial, is that the work of delimitation was carried out from 1904 to 1907 and that, so far as concerns the delimitation of the frontier on the chain of the Dangrek, "the final frontier line was adopted by the Delimitation Commission during the year 1907" in the form of a map or map sheet known in this case as Annex I. On that Annex the area where the Temple is situated is shown as within Cambodia. This "frontier line" is stated in the Application as having been "formally approved" by a Protocol to the Treaty of 1907.

As will subsequently appear this last statement had no foundation. The statement was a complete misapprehension of the true position, first on the part of France, and later by Cambodia, and throws considerable light upon these proceedings and upon the reasons why Cambodia ultimately became obliged to move away from her case as formulated in her Application and resort to other and new grounds upon which to seek a basis for her claim for relief. There was no approval of the frontier line on any part of the Dangrek by the Protocol of 1907. The reference to what had been "formally approved" related to a decision of the Mixed Commission recorded at a meeting of 18 January 1907 when a point on the eastern ex-tremitj7 of the northern frontier between Indo-China and Siam, of which frontier the Dangrek formed the western sector, was determined.

***

In the course of the oral proceedings Cambodia has endeavoured to extend her claim as stated in the Application and Memorial and the grounds on which it rests. But the principal ground on which it relies remains that stated, namely, that Annex I represents the delimitation of the Dangrek frontier by the Mixed Commission under the Treaty of 1904.

***
In its Application and Memorial the Kingdom of Cambodia asked the Court to declare that the territorial sovereignty over the Temple belongs to it. In neither did it describe the actual Temple area over which it claims sovereignty nor has it since done so. It is however inherent in its Application and Memorial that its claim of sovereignty over the Temple is based upon the proposition that Annex I was a delimitation of the Dangrek frontier by the Mixed Commission established under the Treaty of 1904—and solely by that Commission. Sovereignty over the whole area shown on Annex I as south of the frontier line was, it claims, accordingly vested in it. This [p 103] area in fact included the site of the Temple and the land immediately surrounding.

***
I shall first address myself to the principal ground on which Cambodia bases her claim to relief, the only ground indeed which Cambodia, in accordance with her Application, came to the Court to litigate.

The juridical foundation for the claim of Cambodia is to be found in Articles 1 and 3 of the Treaty of 1904. The legal system by virtue of which the frontier was to be delimited is set forth in Article 3 and nowhere else. It was for the Mixed Commission to be created under Article 3, and solely for that body, to make the delimitation.

The Temple finds no mention in the Treaty. Before a decision can be made as to which State has sovereignty over the Temple it is necessary to determine what is the line of the frontier. This is the central question.
The frontier was defined in Article 1 of the Treaty. What was to constitute a sufficient delimitation of that frontier was for the Mixed Commission to decide. It could, if it so wished in respect of any part of the frontier, delimit it by a reference in terms to the text of the Treaty and Protocol. That was a matter entirely for itself to decide.

Whatever the delimitation made, however, it was not a delimitation at large, it was controlled by Article 1 of the Treaty which "determined" the frontier FN1. Subjecc to whatever power of adaption the Mixed Commission may inherently have possessed, the delimitation had to be established on the basis of the criterion laid down in Article 1 which on the Dangrek was the line of the watershed and only on the basis of this criterion. If it was not on the basis of this criterion, any purported delimitation would lack any legal force.
---------------------------------------------------------------------------------------------------------------------FN1 See Article 3 of the Treaty. 101
---------------------------------------------------------------------------------------------------------------------

***
The Minutes of the meeting of the Mixed Commission from the date of its first meeting on 3 January 1905 to that of 18 January 1907, which was to prove its last, were placed before the Court by Thailand.

In the course of oral argument it was faintly suggested by Cam-[p 104]bodia that perhaps one or more Minutes might be missing, or perhaps all decisions taken by the Mixed Commission had not been recorded, or perhaps in particular a decision as to which State sovereignty in the Temple should be attributed was not noted.

There is no foundation for these suggestions. For quite apart from the internal evidence which the Minutes themselves provide there is other documentary evidence which establishes beyond reasonable controversy that the Minutes produced are a complete record of the deliberations and the decisions of the Mixed Commission. A report by Colonel Bernard, the President of the French Commission of Delimitation, of 14 April 1908 to the French Minister of the Colonies in which he forwarded an original copy of the Minutes indicating the number forwarded, establishes this. It is utterly unlikely that any decision of delimitation failed to be recorded in these Minutes.

The Minutes were the work of French and Siamese secretaries appointed by the Mixed Commission at its first meeting, who were "responsible for drawing up the minutes". The practice was for them to be drawn up by the French and submitted to the Siamese for approval and thereafter to be signed respectively by the President of each Commission. The Minutes were manifestly prepared with considerable care and in great detail. No record is to be found within them to support in any way the contention of Cambodia that a frontier line corresponding to Annex I or indeed a frontier line on the Dangrek shown on any map or sketch was at any time either discussed or decided upon by the Mixed Commission. Nor is there any reference at all to the Temple of Preah Vihear which indeed does not appear to have acquired any real importance for either State until many years later.

The matter of the frontier on the Dangrek was referred to at the first meeting of the Mixed Commission early in 1905. It was decided that the work of delimitation of the frontier from the Great Lake to the Dangrek and thence easterly to the Mekong should be postponed until a later season.

Nothing directed to this end was undertaken until December of 1906. It was not till then that the frontier line defined in Article 1 of the Treaty of 1904 received any direct consideration.

At a meeting of the Mixed Commission held on the 2nd of that month it was agreed to make a reconnaissance from the Great Lake to the Dangrek and thence easterly to the river Mekong to the point at which the crest of the mountain range known as the Pnom Padang met that river. This reconnaissance was in fact made and was completed by 10 January 1907, and so far as the Dangrek mountain range is concerned, apparently before the 3rd of that month, since at that date the Mixed Commission was at Ban Mek near the Mekong. [p 105]

The labours of the Mixed Commission had until December 1906 been directed to the region of Luang Prabang FN1, which was far to the north of and beyond the Kingdom of Cambodia, and to the region, within the Kingdom, between the Great Lake and the sea to the south.
---------------------------------------------------------------------------------------------------------------------FN1 Article 2 of Treaty of 1904 and Article II of the Protocol.
---------------------------------------------------------------------------------------------------------------------

In December 1906, when the labours of the Mixed Commission were directed to the frontier defined in Article 1 of the Treaty which was north of the Great Lake, Colonel Bernard had already other ideas as to where the western frontier line south of the Dangrek should be, ideas which were not in conformity with the frontier stipulated in Article 1 of the Treaty of 1904.

He was opposed to any part of the frontier being determined by a parallel and a meridian as laid down in that Article. It is evident from the Minutes of the Mixed Commission that he was determined, if he could, to prevent this taking place. His constant view made known at the first meeting of the Mixed Commission was that "it was absolutely essential that there should, above all, be a frontier that was visible and known to everyone". The frontier as stipulated in Article 1 of the Treaty north of the Great Lake, notwithstanding the clear terms of that Article, was inadmissible FN2.
---------------------------------------------------------------------------------------------------------------------FN2 Minutes of Meeting of 31 January 1905.
---------------------------------------------------------------------------------------------------------------------

At the first meeting of the Mixed Commission in January 1905 he had lost no time in making his views known. The record of the Minutes of that meeting reads as follows:

"Commandant Bernard said that the task which their respective Governments had entrusted to the Commission was that of determining the frontier by following in its main lines the Treaty concluded between France on 13 February 1904... Thus as far as that frontier was concerned to the north of the Great Lake, it was stipulated that the frontier should start from the mouth of the river Stung Roluos and should follow the parallel from that point eastwards until it met the river Kompong Tiam; then turning northwards, it was to lie along the meridian from that meeting point to the mountain chain of the Pnom Dangrek.

Such a frontier was inadmissible between two civilized nations such as France and Siam..."

He never departed from this view. As late as the last meeting held by the Mixed Commission on 18 January 1907 he stated that:

"When accurate maps were available [italics added] a new frontier defined by topographical features should be sought."

Unable, as the Minutes reveal, to persuade the leader of the Siamese Commission to agree with his views on a new frontier line to the north of the Great Lake—the latter who throughout the work of the. Mixed Commission endeavoured as a general rule to [p 106] adhere to the Treaty line, having made it clear that he was not empowered to discuss "any frontier different from that of the Treaty" [italics added]—Colonel Bernard conceded it was in those circumstances necessary for the Mixed Commission to define strictly the parallel and meridian indicated in the Treaty. In so doing, he stated, they would have established the rights of the two States and this would subsequently permit the final frontier in that region to be settled by a system of compensation.

The record reveals that at this point of time Colonel Bernard, and since October of the preceding year, had in mind plans to extend the frontiers of France a considerable distance to the west of those provided in the Treaty of 1904 and was concentrating his efforts to carry them into effect.

This finally he succeeded in accomplishing through the Treaty of 23 March 1907.

***
The leader of the Siamese Commission having been insistent upon following the Treaty line, the two Commissions on 5 December 1906, by compromise, agreed upon a point which should be deemed to be the mouth of the river Stung Roluos within the meaning of Article 1 of the Treaty of 1904, and on 3 January 1907, again by compromise, agreed upon a point which should be deemed to be where the parallel from the former point met the river Prec Kompong Tiam within the meaning of the said Article.

Until these two points could be agreed upon it was not possible either to fix the frontier line from the Great Fake north to the Dangrek, or the commencing point on the frontier of the Dangrek whence it ran in an easterly direction to the Mekong.

Only one further meeting of the Mixed Commission was in fact to be held, namely, on 18 January 1907.

At its meeting of 2 December 1906, when the Mixed Commission's reconnaissance of the Dangrek and easterly to the Mekong was agreed to be made, it had been decided that a Captain Oum—an officer in the French military forces—"would survey the whole region of the Dangrek" whilst other French officers would carry out the survey measurements. A Captain Kerler with another French officer was to start work from the Great Lake working north to join up with the Dangrek where it was met by the meridian. The survey work was done exclusively by French officers, as was almost universally the case throughout the whole of the frontier regions. Captain Oum and Captain Kerler. are those officers whose work on the spot is noted on the left-hand top corner of Annex I. The topographical surveys could not in any manner constitute delimitations. It is common ground between the Parties that the topographical and survey officers were vested with no discretion and had no power to delimit or discuss any question of delimitation of [p 107]
any part of the frontier. Their duties were strictly technical.

Captain Oum was to commence his survey at the far eastern extremity of the Dangrek. He could not have commenced much before 10 December. He worked from east to west. The reconnais-sance made by the Mixed Commission was made from west to east and to the north generally of the crest of the Dangrek. It is utterly unlikely that the Mixed Commission and Captain Oum made any contact and the Minutes do not suggest they did nor does any contemporary document.

On 18 January 1907 the topographical and survey officers were still engaged on their work. As the Minutes of that date reveal, the survey or map sheets of the region were still in course of preparation. Only a little over two weeks had expired since Captains Oum and Kerler had received instructions to commence their surveys, the former operating in particularly difficult terrain where progress was bound to be slow. On 18 January the Mixed Commission was at Pak-Moun on the Mekong. It had completed its reconnaissance of the frontier from the Great Lake to the Mekong at least a week before then.

The following day the two Presidents signed a minute of delimitation in respect of one of the small plots of land which had been agreed to be ceded to France by Siam under Article 8 of the Treaty of 1904. This proved to be the Mixed Commission's last official act.

***
From as early as October 1906 Colonel Bernard had been agitating his superiors to enter into negotiations with the Siamese Government with a view to acquiring "all the old Cambodian provinces". If this could be accomplished it would result in carrying the western boundaries of Indo-China a considerable distance to the west. In that same month he was successful in obtaining official approval of his proposals. From that moment on his activities were mainly directed to this end. It is evident he was anxious to accomplish his purpose as soon as he could and then to wind up the Mixed Commission.

In the first week of March, on the arrival in Bangkok of Mr. Strobel, the adviser to the Siamese Government, his activities increased in their intensity.

On his journey through Paris Mr. Strobel had been informed of difficulties on the frontier north of the Great Lake. From the moment of Mr. Strobel's arrival events moved rapidly. They throw an interesting light upon the circumstances in which the work of the Mixed Commission came to an end. [p 108]

The French topographical officers arrived in Bangkok at different times between 18 February and 4 March. They had by this latter date just completed their work in the field. Provisional maps of the frontier region were not completed until 5 March, and no final maps were in existence. A meeting of the Mixed Commission was provisionally called for 8 March by Colonel Bernard.

On this day however the first steps were taken by Colonel Bernard in discussions with Mr. Strobel to negotiate a new boundary treaty with Siam. The meeting of the Mixed Commission called for the same day was "postponed indefinitely".

Colonel Bernard's conversations with Mr. Strobel continued for six days.

At this point of time His Majesty the King of Siam was about to depart on a visit to France. Mr. Strobel sought to postpone solution of the question of absorption of the "old Cambodian provinces" until the King's return. Colonel Bernard was insistent upon it being settled before the King's departure.

Finally he persuaded Mr. Strobel to his point of view. He was, as the record abundantly reveals, an efficient officer and a dominating personality.

From that moment events moved rapidly.

A draft treaty was first drawn up on 14 March. It was signed on 23 March. Colonel Bernard left Bangkok on the 26th and on 5 April he sailed from Saigon for France where he remained.

No further meeting of the Mixed Commission was held. It dispersed and ceased to exist.

Colonel Bernard has given us his own commentary on those events:

"We had to take as the frontier a certain parallel and then discover at what point that parallel cut across a river called the Preck Kompong Tiam—and from that point we had to draw a meridian as far as the Dangrek mountains. But the river did not exist... A fresh start had therefore to be made and we coald not complete the delimitation without concluding what was really a new treaty.

Moreover the need for tearing up the 1904 Treaty and for preparing a new one had become quite obvious to us the previous year." FN1
------------------------------------------------------------------------------------------------------------FN1 Lecture delivered by Colonel Bernard to the Société de Géographie, 20 December 1907.
------------------------------------------------------------------------------------------------------------

***
Annex I was one of eleven map sheets of the whole frontier regions covered by the Treaty and Protocol of 1904. Whatever survey sketches may have existed previously, these map sheets did not come into being until November of 1907. This is therefore a critical date since at that point of time the Mixed Commission no [p 109] longer existed. Since the Mixed Commission never met after 18 January 1907 and the topographical officers did not complete their work until at least a month later, it is evident that no report from Captain Oum and no sketch or working map in relation to the Dangrek frontier region of any description could ever have been placed before the Mixed Commission for discussion or decision. None ever was.

In the face of the facts stated—all of which are established beyond controversy—it is an unproductive exercise to have recourse to presumptions or inferences from the subsequent conduct of the Parties in an effort to establish that the Mixed Commission must in fact have made a decision delimiting the Dangrek by agreeing to the frontier line shown in or in the form of Annex I or in the form of any sketch or map.

No presumption can be made and no inference can be drawn which is inconsistent with facts incontrovertibly established by the evidence.

These facts admit of only one conclusion, namely: that the frontier line on Annex I was not a line agreed upon by the Mixed Commission as a delimitation of the frontier of the Dangrek.

***
Independently of the facts stated it would seem a little unlikely to say the least that, when the Treaty and Protocol of 1907 was drafted, if there had been any map or sketch agreed to by the Mixed Commission which delineated the frontier line on any part of the Dangrek or the Pnom Padang east to the river Mekong that no reference whatever to such a map or sketch would have been made in the text of that Treaty.

Article I of the Protocol to the Treaty of 1907 described the new frontier between Indo-China and Siam. Included within the description was the frontier which extended along the Dangrek— from a point considerably west of the 1904 Treaty line—and ran across the Pnom Padang easterly to the river Mekong. Yet no map or sketch relating to the Dangrek is mentioned.

There was indeed in Article I of the Protocol of 1907 a reference to a sketch of the frontier, but this sketch did not cover the region of the Dangrek shown in Annex I. There was also a reference therein to a line (tracé) adopted by the Mixed Commission. This however related to the eastern extremity of the frontier above mentioned, and to a decision taken by the Mixed Commission at its last meeting on 18 January 1907 and recorded in the Minutes of that date to the effect that the thalweg of a certain river—the Huei Don—should be the agreed point at which the crest of the Pnom Padang met the river Mekong within the meaning of Article 1 of the Treaty of 1904. [p 110]

Colonel Bernard played the principal role in the drafting of the Treaty and Protocol of 1907 particularly, I would think, in the technical description of the frontier. If an inference may be drawn it would seem permissible to assume, certainly all the probabilities would suggest, that at the date of that Treaty and Protocol, namely 23 March 1907, if there had been any map or sketch which up to that point of time had been agreed to by the Mixed Commission as delimiting any part of the frontiers from the Kel Pass on the Dangrek along the Pnom Padang to the east, it would at least have warranted some reference. The fact that there is no mention of any such decision is in the circumstances powerful, indeed, I think, overwhelming evidence that no such delimitation had been made.

Moreover, having in mind the great importance which today is said to have attached to the Temple in 1907-1908, it seems scarcely conceivable that, if as has been suggested, the Mixed Commission during its reconnaissance of the Dangrek made some decision of delimitation dealing with the Temple or Temple area, or the frontier in the region of the Temple, that it should be mentioned neither in the Minutes nor in the Treaty and Protocol of 1907 nor in any contemporaneous document.
***

The reference in Article I of the Protocol of 1907 to a sketch and "trace" immediately following the description of the frontier line on the Dangrek and Pnom Padang is, I think, of no little importance in this case. It has a distinct bearing upon the manner in which Cambodia has presented her case and why quite late in the proceedings she shifted from the ground on which she relied in her Application and added grounds which were neither set forth nor foreshadowed therein.

It is evident from paragraph 6 of the Application that Cambodia regarded this reference in Article I of the Protocol of 1907 as a formal treaty confirmation of the frontier line shown in Annex I.

In this—a very important part of her case—she was mistaken. It is evident also that France and later Cambodia were under a total misapprehension as to the meaning of this reference in the Protocol of 1907 for very many years.

***
When the meeting of the Mixed Commission of 18 January 1907 had concluded, Colonel Bernard believed that the work of the Mixed Commission, at least in the field, had been completed. He said so in so many words in a telegram of the 28/29 January I907. [p 111]

If there were any decision of the Mixed Commission made by it during its reconnaissance of the Dangrek which, for some quite unknown reason, was not in any manner referred to in either the Minutes of 3 January or 18 January—or indeed on the next day when they met again together—it is manifest that it could not have been in the form of any line appearing on any sketch or map since, not only was there not then even a topographical sketch map of the frontier region in existence, but the topographical survey work, without which no line of the watershed of any description was capable of being drawn up and decided upon, was unfinished. Captain Oum was still in the Dangrek.

If then there had been any prior decision delimiting the northern frontier when the Mixed Commission held its meeting on 18 January 1907, it could never have been a decision to adopt a line corresponding with that on Annex I, or a line shown on a sketch or map. It would seem probable that it could only have been one to the effect that between the point on the Kel Pass on the west and an agreed point at the Mekong on the east the frontier line would be that stipulated in Article 1 of the Treaty, namely the line of the watershed on the Dangrek and the crest on the Pnom Padang.

Although, however, it is established that there never could have been any delimitation which adopted a line on any sketch or map, it does not follow that there was no delimitation of the Dangrek by, the Mixed Commission.

The question whether there was any delimitation of the Dangrek, either in itself, or as part of the total northern frontier, and, if there were, in what form, will now be pursued.

***
Since the Minutes of the Mixed Commission cover, as I am satisfied they do, all meetings of the Mixed Commission and record all decisions taken by it, if there were any delimitation of the northern frontier line, in particular of the Dangrek, it should be capable of being ascertained from them.

One possibility has been canvassed during the case, namely that during the reconnaissance of the northern frontier made by the Mixed Commission there may have been a decision taken by it, in which it was decided that the frontier line in the region of the Temple should for some local or other reason run in such a manner that the Temple would be on the Cambodian side of the boundary.

Apart from what I think is the inherent unlikelihood of such a decision, it is straining credulity too far to suggest that it would find no mention in the Minutes of the Mixed Commission. I am [p 112] quite unconvinced by attempts to explain this away by a suggestion that perhaps there was not sufficient opportunity to record the decision after the Mixed Commission had completed its reconnaissance, and that perhaps such a decision or at least one which related to the delimitation of the Dangrek generally would have been recorded at the meeting called for 8 March had it been held.

There was an opportunity on 3 January to record whatever decisions the Mixed Commission may have made in the course of its reconnaissance. If that opportunity was not sufficient there was another on the 18th of that month. Moreover, if any delimitation in relation to the Temple region had been made by the Mixed Commission it passes understanding why it—or any decision other than those recorded in the Minutes—was not mentioned at any time by Colonel Bernard in his numerous official letters and reports to his superiors at the time, and in particular was not mentioned in his report of 20 February 1907 to the French Minister in Bangkok—a document of cardinal importance in the case—when he reviewed in full the delimitation under the 1904 Treaty made in the course of its final campaign and covering as it did the frontier line from the Great Lake to the Mekong.

Moreover Colonel Bernard—as appears from his final report dated 14 April 1908 to the French Minister of the Colonies before referred to, had "in letters written day by day" reported to the Minister "all the incidents that occurred" during the course of the delimitation. Yet not the slightest hint of any decision in connection with the Temple area or the region of the Temple is to be found.
Colonel Bernard attached to this report a number of documents including the Minutes of the Mixed Commission which in his view were "from the diplomatic point of view of considerable importance".

It does not seem likely that Colonel Bernard would have sent incomplete minutes or if for any reason there had, on 18 January 1907, been any decisions of delimitation which had not been rec-orded, particularly a decision relating to the Temple itself, that he would have failed to make the record complete by referring to them.
***
On 18 January 1907 the Mixed Commission believed that it had completed the task of delimitation assigned to it under the Treaty of 1904.

The Minutes note that on that day it had fixed the point at which the crest line of the Pnom Padang met the Mekong within [p 113] the meaning of Article 1 of the Treaty of 1904. Immediately following this notation it is recorded that the frontier line had been "thus determined".

What frontier line is referred to? Was it just the frontier line at the point at which the northern frontier line met the Mekong?

In my view the reference is to the whole frontier line from the Great Lake to the Mekong which was the subject of the Mixed Commission's third and last campaign directed, to the delimitation of the frontier defined in Article 1 of the Treaty of 1904.

The question is whether the evidence establishes that the Mixed Commission did delimit the whole frontier line defined in that Article; and if so whether there can, with sufficient certainty, be extracted from the Minutes the nature of the delimitation made on the Dangrek.

No difficulty presents itself in ascertaining the delimitation made by the Mixed Commission from the Great Lake to the Dangrek. No difficulty arises in fixing on the Dangrek the western extremity of the northern frontier as determined by it. None arises in respect to the eastern extremity of that frontier.

The question however is whether there is evidence which sufficiently establishes a delimitation—particularly on the Dangrek— of the frontier between these two extremities.

***
Since there is not to be found in the Minutes of the Mixed Commission a record of a decision of delimitation specifically referring to the Dangrek, it might appear that the conclusion should be that there never was a delimitation of the Dangrek of any description.

In the course of sifting the evidence I have however become persuaded to the opinion that the probabilities and the evidence both point to the conclusion that the Mixed Commission did make a decision delimitating the Dangrek and it did so by determining that, along the whole of the northern frontier between two agreed points, one on its western, the other on its eastern extremity, the frontier should follow the treaty line; that of the line of the watershed on the Dangrek and the crestline of the Pnom Padang.

The northern frontier from the Kel Pass which was its western extremity, to the point on the Mekong where the Pnom Padang ran down to it which was its eastern, was one frontier line. Because however the Temple happens to be situated on the Dangrek range and because Annex I happens to cover that region of the Dangrek on which the Temple is situated, atten+ion throughout this case has been concentrated on that part of the Dangrek which is within the purview of Annex I and more particularly on that small portion of the frontier line in Annex I which is immediately adjacent to the Temple. This fixation of attention on Annex I and upon this small [p 114] sector of the frontier line adjacent to the Temple has tended to distract attention from the fact that the northern frontier was not a number of separate frontier sectors and was not considered by the Mixed Commission on that basis. It was one line of frontier and the Mixed Commission dealt with it as such.

***
The beginning of December 1906 marked what Colonel Bernard referred to as the third campaign of delimitation.

At that point of time the Commission had completed its task of delimitation of all the frontier defined in the Treaty and Protocol of 1904 with the exception only of that from the Great Lake north to the Dangrek and thence easterly to the Mekong.

As has been noted the western frontier line north of the Great Lake to the Dangrek had been delimited by decisions identifying the meridian and the parallel. Colonel Bernard remained dissatisfied. He was awaiting preparation of the maps of the region known as Siem Reap so as to take up again with the Siamese Commission the matter of substituting a natural and visible line for what he regarded as the artificial line stipulated by the Treaty.

Subject however to this particular point which was not one of delimitation but of exchange of territory to achieve a natural line of frontier, the work of delimitation, in Colonel Bernard's view at least, was completed.

It is unlikely that the Mixed Commission having, during the season 1906-1907, set itself the task of delimiting the frontier from the Great Lake to the Mekong would have left its work unfinished, the northern frontier undelimited. It seems more probable that their work was finished when the meeting of 18 January concluded, and that the only reason why the meeting called for 8 March was cancelled and the Mixed Commission thereafter ceased to function was because the subject-matter on which it would have deliberated, namely the substitution by way of a system of compensation of a natural and visible line for the treaty line of the parallel and meridian, was about to be settled by the Treaty of 1907.

It hardly seems reasonable to believe that Colonel Bernard would have departed for France as he did unless he was fully satisfied that, with the signing of the 1907 Treaty, not only had the problem of the artificial line been resolved, but also the Mixed Commission had completed its task of delimitation of the northern frontier.
That this is the view which he genuinely held appears from his telegram of the end of January 1907 to the French Minister at Bangkok, in which he said: [p 115]

"delimitation work accomplished without incident. Frontier line definitively determined except the Siem Reap region."

This is confirmed by a despatch dated 31 January 1907 on behalf of the French Minister of Foreign Affairs to the French Minister of the Colonies, in which it is said:

"The representative of the Republic in Siam informs me that Colonel Bernard, after completing the work of delimitation of the Siamese frontier, has just left Ubone for Bangkok where he is expected to arrive on 10 February. I understand that, throughout the operations, relations with the Royal Commissioners left nothing to be desired and that the frontier line has been definitively determined except in respect of the region of Siem Reap."

I do not doubt that the view expressed in these two documents, which is confirmed in other official documents of the same time, correctly represents the views of the Presidents of both the French and the Siamese Commissions.

The statement that the frontier had been definitively determined is consistent with the Minutes of the Second Mixed Commission appointed under the Treaty of 1907 to delimit the new frontiers in which, when dealing with a sketch of the proposed frontier of the Dangrek west of the Kel Pass placed before it on 22 March 1908, there appears the statement "the latter pass is the point where the new frontier line rejoins the former one".

Since there is no reason to doubt the statements made by Colonel Bernard at the time, it seems proper to conclude that the northern frontier in fact had been delimited and that such delimitation must have been completed by 18 January 1907, the date of the Mixed Commission's last meeting.

On that date the Minutes record as follows:

"Colonel Bernard passed to the question of the determination of the frontier in the region of Pnom Pa Dang (Phu Pha Dang). According to the terms of the treaty that frontier followed the crest... as far as the Mekong... In order to have a very distinct frontier in the immediate neighbourhood of the river the thalweg of the Huei Don could be taken as the boundary. The frontier would go up that thalweg [i.e. of the Huei Don] as far as the source of the watercourse and would then follow the crest of the Phu Pha Dang to the south west. The valleys of all the watercourses which flowed into the Mekong to the east and to the south of that line would belong to French Indo-China and those of all the watercourses which flowed into the Mekong or into the Semoun on the west and to the north would belong to Siam."

The President of the Siamese Commission accepted this proposal, immediately following which there appear the words previously referred:
"The frontier line having been thus determined..."

It is known that at this date the topographical and survey officers were in the field, from which they were not to return until a month [p 116] and more later. It would seem however that the Mixed Commission, having made this decision—the last decision of delimitation set out in the Minutes—regarded the frontier line as having been determined by it—at least so far as it could be done by it on the spot.

***

The statement that "The frontier line" had been "thus determined" is not free from doubt. It could and on its face appears to refer solely to the fixing of the point at the Mekong and the frontier immediately adjacent. Read however in the light of the repeated statement of Colonel Bernard that the whole frontier had been definitively determined, the Minutes of 18 January are I think a reference to the whole frontier line to the south west of the Mekong —from the reconnaissance of which frontier the Mixed Commission had just returned—and that the decision fixing the point at which the frontier met the Mekong represented the last decision required to be taken to complete the delimitation of the whole frontier.

A reading of the Minutes which covers this third and last campaign of delimitation and of the contemporaneous documents in my opinion confirms this.

It was for the Mixed Commission and for it alone to determine what was a sufficient delimitation. It was at liberty to delimit any part of the frontier by reference to its Treaty definition. It. is significant that the Mixed Commission under the 1907 Treaty in delimiting the frontier on the Dangrek west of Kel Pass did precisely this.

***
Any agreement to deviate from the Treaty line of the watershed on the Dangrek under any inherent power of adaptation is excluded since, not only is there no evidence whatever to suggest that the Mixed Commission ever contemplated any deviation from the line of the watershed, but at the very last meeting of the Mixed Commission and on the same day on which the decision fixing the frontier point on the Mekong was noted, the President of the Siamese Commission had made it clear he had no authority to discuss "any frontier different from that of the Treaty". Furthermore, since any question of there having been some unrecorded delimitation of or in relation to the region of the Temple area or the Temple itself must, for reasons already given, be dismissed from consideration, there seems little doubt that, if the delimitation of the frontier under the Treaty was completed, as Colonel Bernard specifically states as the fact, and as the Minutes themselves go to indicate, it must have been the line of the watershed on the Dangrek which [p 117] it was agreed should constitute the frontier line in that region.

The Presidents of the two Commissions were practical men. The mountain ranges of the Dangrek and the Pnom Pa Dang were in inhospitable and forbidding terrain. They were called on to make a practical decision.

No question of demarking the northern frontier ever arose and, so far as the record shows, that frontier has never been demarked during the fifty odd intervening years. It remains much the same today as it was then. The Mixed Commission appears to have decided to fix the points of the extremities of the northern frontier on the west and on the east and to have agreed that between those two points the frontier needed no further delimitation other than the Treaty itself provided.

The stipulation of the line of the watershed on the Dangrek—and the crest line on the Pnom Padang was itself an obvious and appropriate way of defining definitively and with certainty the northern frontier line. There is no reason why the Mixed Commission having once fixed or decided to fix the points of its extremities should not have delimited that frontier by reference to its definition in the Treaty. The line of the watershed—and the crest line—were natural and permanent lines. There are, as the Judgment of the Court points out, boundary treaties which do no more than refer to a watershed line or a crest line and which make no provision for any further delimitation. It is not evident why the Mixed Commission should have felt obliged to give to the line of the watershed —or the crest line—any more specific delimitation than that which the Treaty already provided. As already noted, the Mixed Commission under the 1907 Treaty in delimiting the Dangrek west of the Kel Pass did not feel obliged to do so. That Mixed Commission recorded its decision specifically to read "From the last mentioned point the frontier inclines to the East, following the watershed between the basin of the Great Lake and that of the Semoun as far as the Kel Pass."

It is a misconception of the functions of the Mixed Commission to suggest that it was bound to give or should be expected to have given a further definition to the northern frontier or any part of it beyond that which the Treaty already provided.

The northern frontier was after all a part only, and a lesser part both in magnitude and importance, of the whole frontier described in the Treaty and Protocol of 1904.

It is moreover in my opinion without warrant to suggest that France and Siam did not attach any special importance to the line of the watershed as such. This suggestion is not reconcilable with [p 118] the fact that in the Treaty of 1907, more than two months after the Mixed Commission had held its last meeting, it is the line of the watershed which is again stipulated should be the frontier line on the Dangrek and when in 1949 France and later Cambodia, in 1954, protested Thailand's occupancy of the Temple area, it was the line of the watershed as defined in the Treaty of 1907 which, it was insisted, continued to be the frontier between the two States.

In particular there is no reason whatever why the Mixed Commission should not have agreed that, from a fixed point on the Dangrek where that range was met by the meridian, the frontier should be the line of the watershed on the Dangrek until it joined the Pnom Padang and then the line of the crest of that mountain range as far as the fixed point at tfie Mekong. Indeed there seems no practical reason why this should not have been precisely the decision it did take.

Nor is there any reason why a delimitation of the Dangrek required any line shown on any map either to establish a delimitation or to confirm one. Nowhere does the Treaty of 1904 give any in-dication that any map was necessary or considered desirable to accomplish a delimitation of any part of the frontier.

The assertion that it was the map line of the watershed, not the Treaty line of the watershed, which was regarded as of overriding importance, I do not find supportable. If the assertion were correct, it would mean that agreement between the two States was not in 1908-1909 a mere formality as has been contended; it was the very gist of the delimitation of the Dangrek. The map would itself constitute the delimitation. If the assertion were correct all that needs to be said is that the two States in 1908-1909 could not have conducted themselves in a more casual and inconsequential manner in matters affecting territorial sovereignty.

If the delimitation of the northern frontier had been made by the Mixed Commission in 1906-1907 in terms of the line of the watershed as defined in Article 1 of the Treaty of 1904, a map subsequently produced by France or Siam was not in any manner necessary to give effect to that decision. A frontier line shown on such a map would possess no probative value—except to the extent to which it was in conformity with the decision of delimitation of which the map in a general sense might be said to have been an outcome.

If the Mixed Commission did in fact delimit the Dangrek, it would seem evident that it did so by reference to the Treaty line of the watershed.

That this was the course followed by the Mixed Commission finds I think confirmation in a number of documents. [p 119]

In the first place the procedure followed accords with that laid down by the Mixed Commission at the commencement of its labours in 1905, namely that it would be sufficient to determine the principal points through which the frontier in any region passed FN1.
---------------------------------------------------------------------------------------------------------------------FN1 Minute of Meeting of 7 February 1905.
---------------------------------------------------------------------------------------------------------------------

It accords also with the procedure which, as will appear, was followed in other frontier regions covered by the Treaty of 1904 where a watershed line was to form part of the frontier line FN2.
---------------------------------------------------------------------------------------------------------------------FN2 See Article 2 of the Treaty and Articles I and II of the Protocol. 117
---------------------------------------------------------------------------------------------------------------------

The procedure appears to have been constant.

Light upon the meaning of the decision of the Mixed Commission, recorded in the Minutes of its Meeting of 18 January 1907, is shed by a letter of the same date written by Colonel Bernard immediately after the meeting to the Governor-General of Indo-China in which he said:

"The frontier line which I have indicated summarily on the attached sheet is as follows: Starting from the Mekong the frontier follows the course of the Nam Lon as far as its source and thereafter the crest of the Phu Pha Dang [Pnom Padang] to the southwest as far as the watershed between the Mekong and the Nam Moun. The valleys of all the watercourses which are tributaries of the Mekong and are situated to the east and south of the line belong to French Indo-China..."

This is clearly enough a reference not only to the crest line on the Pnom Padang which the frontier line was to follow but as well to the watershed line on the Dangrek in terms of Article 1 of the Treaty of 1904.

Attached to the letter was a rough sketch. It shows the point at which the frontier met the Mekong, as agreed on 18 January 1907, and the general direction of the line of frontier for a short distance south west of that point.

The report by Colonel Bernard of 20 February 1907 to the French Minister in Bangkok, already referred to, in which he reviewed at length the third and last campaign of the Mixed Commission, affords further confirmation.

Dealing with the frontier line of the Dangrek and the Pnom Padang as far as the Mekong he had however little to say, but what he did say is eloquent enough. Read in the light of the facts which have been established, it does more than negative any suggestion that there may have been some special delimitation in respect to the Temple area, or that the two Presidents may have decided to depart from the Treaty line of the watershed; it also establishes that a delimitation of the Dangrek was made and how it was made.

Colonel Bernard reported as follows: [p 120]

"All along the Dangrek and as far as the Mekong the fixing of the frontier could not have involved any difficulty. It was only a question of determining at what point the Pnom Padang adjoins the Mekong. On this point there was no possible discussion for the mountain joins the river at one point only about seven kilometres below Paknam."

At the date of this report it will be recalled not even a provisional map of the Dangrek or Pnom Padang frontier regions was in existence.

Further, in the Protocol of the Treaty of 23 March 1907, in the drafting of which Colonel Bernard had played such a key part, Article I thereof describes the new frontier which had been agreed to in the March negotiations.

After describing the boundaries of the new frontiers in the south and the west, it indicated the point some hundred kilometres more or less to the west of the Kel Pass where the new western frontier met the Dangrek. It went on to provide:

"From the above-mentioned point situated on the crest of the Dang-Rek, the frontier follows the watershed between the basin of the Great Lake and the Mekong on the one side and the basin of the Nam Moun on the other and reaches the Mekong downstream of Pak-Moun at the mouth of the Huei-Doue [ Huei Don ], in conformity with the line [tracé] adopted by the preceding Commission of Delimitation on the 18th January, 1907."

In the light of this treaty provision it cannot, I think, be contemplated that any decision of the Mixed Commission under the Treaty of 1904 could have departed in any way from the line of the watershed.

Colonel Bernard, who knew exactly what was decided by the Mixed Commission during the third campaign and the basis on which the delimitation of the northern frontier was effected, must have understood that the fixing of the point at which the Pnom Padang adjoined the Mekong, as recorded in the Minutes of 18 January 1907, was the last decision necessary to be taken to delimit the whole of the northern frontier.

The fact that the second Mixed Commission, under the Treaty and Protocol of 1907, delimited the frontier from west of the Kel Pass until it reached that pass by strictly adhering to the line of the watershed, serves to show a consistency of treatment by both Commissions of the whole frontier line of the Dangrek.

When Colonel Bernard reported that the frontiers had been definitively determined he was I think stating the fact. The manner in which the delimitation of the northern frontier was effected is apparent. Once the point on the Mekong had been agreed to, that frontier followed the treaty line stipulated in Article 1, namely the crest of the Pnom Padang and the watershed of the Dangrek, until [p 121] it reached the point at which on the latter mountain range it met the meridian mentioned in the article. Whatever decision or viewpoint was arrived at or expressed by the two Presidents during their reconnaissance of the Dangrek and the Pnom Padang, or at any time, would accord with this view.

Colonel Bernard has left his testimony.

In the lecture given by him in Paris on 20 December 1907, he described the three campaigns of delimitation from 1905 to 1907. What he has to say he says with illuminating conciseness. These are his words:

"Almost everywhere it was the watershed which formed the frontier and there was room for argument only at the two extremities."

His testimony remains to explain the meaning which should, I am convinced, be given to the Minutes which cover the third and last campaign of the Mixed Commission. The view he expressed seems eminently a commonsense one.

***

The review made of the Minutes and the contemporaneous documents lead I think to the following conclusions:

1. There was no adaptation of the treaty line of the watershed on the Dangrek by the Mixed Commission to meet any local or special problem, condition or circumstance.

2. There was no decison of delimitation which specifically dealt with the Temple region or area.

3. There was no decision of any kind to deviate from the line of the watershed. On the contrary it must be inferred that the Mixed Commission decided to adhere strictly to that line.

4. There was a delimitation of the northern frontier. This delimitation included the Dangrek.

5. The delimitation of the frontier line on the Dangrek was that it should follow the treaty line of the watershed.

It follows that if the frontier line shown on Annex I has any probative value it must find its authority within the limits of the 'decision of the Mixed Commission. It was the decision of the Mixed Commission which was binding upon France and Siam, not any map which purports to reflect that decision. The map merely notes or purports to note that decision.

If the line of frontier shown on Annex I does not accord with that decision to the extent to which it does not, it is devoid of probative value, unless of course it has since acquired probative force from some other source. [p 122]

***
Annex I in fact is not in conformity with the treaty line of the watershed stipulated in Article 1 of the Treaty of 1904. Leaving aside for the moment the comparatively small and limited area immediately adjacent to the site of the Temple, elsewhere the frontier line delineated in Annex I deviates considerably from the treaty line of the watershed. Having regard to the expert evidence placed before the Court by both Cambodia and Thailand, this cannot be disputed.

This deviation was due to a serious mistake in the construction of Annex I made in the line of the watershed close to the site of the Temple, a mistake caused by an incorrect location of a river known as the O'Tasem. This mistake resulted in throwing the frontier line shown on Annex I completely out of alignment with the line of the watershed in the region of the Temple. The result was to leave the Temple wholly within the territory of Cambodia.

The experts from both sides are also in agreement that in the small and limited area immediately adjacent to the Temple the frontier line shown on Annex I is not today—and I am satisfied was not in 1906-1908—the line of the watershed. They differed only to the extent that whereas the experts on behalf of Cambodia showed the line of the watershed as suddenly turning north from the cliff face on the south immediately before it reaches the western and southernmost side of the Temple and so just barely bringing the Temple within the Cambodian side of the watershed line, those on behalf of Thailand showed the watershed line as continuing to follow generally the line of the cliff face and so bringing the Temple within the Thai side of the line.

The error in the frontier line shown in Annex I caused by the wrong location thereon of the river O'Tasem and the effect of that error in relation to the frontier line near the Temple shown on Annex I needs further explanation.

The river O'Tasem in fact passes to the south of a mountain known as Pnom Trap—which is situate but a few kilometres to the west of the Temple. The course of the river as it is today is the same as it was at the beginning of this century and for hundreds of years before then. Annex I however places the river as running around this mountain to the north of it.

The nature of the mistake is made clear by Professor Schermerhorn, the Dean of the International Training Centre for Aerial Survey at Delft, and his explanation was fully confirmed by the observations and evidence of one of his officers, a Dr. Ackermann, who went to the area to qualify himself to give evidence of what [p 123]

he observed on the spot.

Professor Schermerhorn in his evidence stated:

"It is obvious that the border line shown on the Annex I map was drawn by constructing the watershed line in accordance with the contour lines represented there. This construction was done correctly on the basis of the given contour lines. However, due to the mistake about the O'Tasem river, the line of the watershed is shifted incorrectly to the north, placing the Pnom Trap mountain completely in Cambodian territory that is to say south of the border line as drawn in the Annex I map. This displacement of the watershed line to the north goes up to two kilometres at certain points. If this mistake is rectified in the Annex I map then the watershed constructed on the basis of the correct contour lines would be in agreement with the I.T.C. map [that of the International Training Centre at Delft]. In that case the watershed would run over the Pnom Trap mountain and go from there along the southern rim of the Phra Viharn mountain to the temple."

This was a fundamental error in the construction of the frontier line in Annex I. The significance of this mistake in relation to the frontier line shown on Annex I in this region is evident having regard to the close proximity of the Pnom Trap mountain to the Temple and the mountain on which it stands. By placing the river O'Tasem to the north of Pnom Trap mountain the line of the watershed as shown on Annex I was thrown considerably north of the correct watershed line, attributing to Cambodia territory to which she was not entitled. The fact that from the southern edge of the cliff face on which the Temple is situate to the watershed line shown on Annex I immediately and directly to the north thereof is a distance of only some two kilometres is an indication of the importance of this mistake.

The line of the watershed shown on Annex I is also known to be wrong at the Kel Pass, where it wrongly attributes certain territory to Cambodia. Though this has no direct bearing on the Temple area—it is far to the west of it—it has however a bearing on the frontier line shown on Annex I, more particularly so since this mistake was discovered in 1908 and corrected by two survey officers appointed by the second Mixed Commission to put down boundary marks in the vicinity of Kel Pass. The fact is that at the Kel Pass the accepted boundary is not, and has not since 1908, been, that shown on Annex I.

Finally, having regard to the technical evidence presented to the Court by both Cambodia and Thailand, I am left in no doubt that the line- of the watershed today—and in 1904—runs along the southern rim of the Phra Viharn mountain, thus placing the Temple on the Thai side of the line. [p 124]

The frontier line placed on Annex I accordingly is not in conformity with the delimitation of the Dangrek by the Mixed Commission/Alternatively if the fact be that there was no delimitation by the Mixed Commission of the Dangrek the frontier line on Annex I is not in conformity with the treaty line, in particular, in the region of the Temple. The line shown on Annex I is not and was not the line of the watershed.
***
In 1908, when Annex I came into existence, the law as between France and Siam was the line of the watershed, whether based on a decision of the Mixed Commission or—on the assumption there was no delimitation—on the definition of the frontier in Article 1 of the Treaty of 1904, or more precisely in Article I of the Protocol to the Treaty of 1907. This line could not be altered by the unilateral act of either France or Siam.

***
Neither France nor Siam, when the map was issued in 1908, was aware that the frontier line shown in Annex I was not in conformity with the line of the watershed. France certainly believed it was. It was in the confidence of that belief and on the basis that it was correct that she distributed copies of the maps. Siam had no reason to believe that it was not. The mistake in Annex I caused by the misplacement of the river O'Tasem was indeed not discovered by Thailand or France or Cambodia until these proceedings had been commenced. Indeed Thailand had no cause to think of any error in the watershed line shown on Annex I until an officer of the Royal Thai Survey Department, during the course of a survey of the border between Thailand and Indo-China, and taking the watershed along the Dangrek range as the dividing line, concluded that Mount Phra Viharn lay in Thai territory.

Another survey was carried out in 1937. Again the watershed line was taken as the frontier line. The same conclusion was reached.

Up till around 1935-1937 it would not appear there was any particular reason why Thailand should have questioned the accuracy of France's map.

Both France and Siam, acting in perfect good faith, believed the line on Annex I—as well no doubt the frontier lines shown on each of the other ten map sheets—correctly translated the decisions of the Mixed Commission. [p 125]

***
When Annex I appeared, the frontier line delineated thereon was not binding on either Siam or France. Unless Siam is by her conduct precluded from alleging that it was not—which is an entirely different question—all that may be envisaged is the creation of a new obligation binding upon her, voluntarily entered into, a new obligation entered into between herself and France by which each State agreed to accept the line in Annex I as the established frontier between them.

***
It is important to review the circumstances in which the map sheets came into existence, were printed and distributed.

Neither Annex I nor any of the ten other map sheets which went to make the total map of the frontier regions of the 1904 Treaty came into existence solely in response to a request of Siam. In 1904-1907 there were few reliable maps possessed by either France or Siam of any part of these frontier regions. This finds ample confirmation in the Minutes of the Mixed Commission, particularly those of 17 January 1906, when Colonel Bernard expressed the view that it would be of value to have a more complete map.

"At that moment", he said, "there was no satisfactory map in existence and it would be useful for the two countries to have one. Captain Tixier and Lieutenant See would ... be able to extend the map as far as the Menam on the one hand and as far as Phetchabun and Nong-Khai on the other."

It was just a few weeks before this that the Siamese Government had made a request

"that the map of the whole frontier region should be executed by French officers".

It is quite evident that this was not a mere map to show the frontier line but a general map of the frontier regions.

As will appear, and I think quite sufficiently, France, for her own purposes, wanted general maps of the frontier regions and wanted them to extend as far as possible each side of the frontier lines. There is little doubt she intended to construct these maps during the course of the work of the Delimitation Commission and intended to do this before any request was made by Siam.

In November of 1907—two years after the Siamese Government made its request—the map consisting of the eleven sheets was completed. [p 126]

It was not until July of 1907 that Colonel Bernard, then in France, sought the approval of the French Minister of the Colonies for the publication of the map then being drawn up "by the Franco-Siamese Delimitation Commission of which he was the President" and requested the provision of funds for that purpose. The decision to publish the maps was made by the Minister; Siam was not consulted about it. The printing and publication of the map did not follow, as a matter of course, from the operations of the Mixed Commission in 1905-1907. Ultimately, funds were authorized for publication of the "Bernard Commission map" to be provided out of the budget of Indo-China.

An order for printing was given to a map publisher in Paris. 1,000 copies were ordered to be struck off. These were to be delivered to the Ministry of the Colonies by June of 1908. They were delivered around that time.
About May of 1908, Colonel Bernard gave instructions for the distribution of the maps when printed. Copies were to go to the geographical service of the French Ministry of the Colonies, to the French Ministry of Foreign Affairs, to the Siamese Government and to members of "the two Commissions" and a number of copies to different national and foreign geographical societies. Over 700 were to be delivered to the French Ministry of the Colonies for despatch to Indo-China. 100 were to be made available to the publisher for sale.

The copies to be delivered to the Siamese Government—50 in all —were handed personally to the Siamese Minister in Paris without any covering letter. Subsequently further copies were requested by Siam. There was no written communication of any kind from the French Government to the Siamese Government in connection with the map. No comment from Siam was at any time sought. Indeed, none I am satisfied was expected.

There is no evidence whatever even to suggest that Siam knew of the contents of any of the map sheets before they were delivered to its Minister in Paris. It is unlikely that she could have.

Siam was not consulted at any stage whilst the map sheets were in the course of preparation, nor was she consulted on the distribution to be made. The French authorities went ahead with printing, publication and distribution of the maps solely of their own accord, without seeking the prior views or approval of Siam.

To the extent the map sheets showed frontier lines, it is evident that the details thereof appearing on them were based upon field notes and topographical and survey calculations made by a number of French officers whose names are noted on each of the sheets as having done the work on the ground. Siam had no access whatever to these basic materials. The documents that served for drawing up [p 127] the maps were then in France.

Nor is there any evidence that they were ever made available to her and I am satisfied it is wholly unlikely that they were. In any case, there was no way in which Siam could have checked the frontier line delineated on Annex I even if it might, in all the circumstances, reasonably have been expected that she should have done so, without herself undertaking an independent topographical survey of the frontiers including the Dangrek, a task for which at that time, as France knew, and as the Minutes of the Mixed Commission and contemporaneous documents sufficiently reveal, she was not technically equipped to undertake.

Such maps of her own as Siam had in 1908 were uncoordinated. The receipt of these maps drawn by French officers must no doubt have provided an occasion in its way. They were however French maps expressed in Roman characters. "French maps", stated Commandant Montguers, the President of the Mixed Commission under the Treaty of 1907, in a letter of 17 June 1908 to the Governor-General of Indo-China, were "of no great use" to Siam. It was for this very reason that it was agreed between France and Siam that a Siamese map "should be drawn up by French officers assisted by Siamese officers".

This resulted in the establishment of the Transcription Committee.

It has been suggested on behalf of Cambodia that on this occasion Siam had the opportunity to check the frontier line and if she did not avail herself of it that was her own fault.

The contention completely misapprehends the function of the Transcription Committee. It had nothing to do with the checking of frontiers. Its sole function was to achieve a system of transcription of names on the French maps.

Little is known about the work of the Committee. It met for the first time on 25 March 1909 and the Minutes of its Meeting are in the record. The problem was to transcribe names of places. The map sheets, written as they were in Roman characters, were not likely to be understood, so the Minutes record, by certain of the Siamese officers who might have to use them. A system of tran-scription from Roman characters to Siamese characters and vice versa was the task which the Committee had to discharge, a task further complicated by the fact that, in the basin of the Great Lake, many villages bore both a Cambodian and Siamese name. It was this problem and only this problem which the Transcription Committee was called upon to deal with.

Moreover, there was no real reason in any case why the Siamese members of the Transcription Committee should think of checking the frontier lines, not only because it was not within the task which was allotted to them, but because both States at that time had no [p 128] reason to think there was any mistake in the maps; both States proceeded on the assumption they were correctly delineated.
***
The circumstances in which the maps came into existence and were distributed is of importance as providing part of the background against which the conduct of France and Siam is to be evaluated, particularly in considering whether the adverse inferences which are sought to be drawn from Thailand's silence and lack of protest on the line shown on Annex I bear any relation to the realities.

Before however considering whether the conduct of the two States created an implied conventional agreement between them that the line shown on Annex I should be the established frontier line between them, there are a few observations of a general character which I think are apposite.

It is easy to fall into the error of judging the events of long ago by present day standards, indeed sometimes by standards which do not always have relation to real life.

In determining what inferences may or should be drawn from Thailand's silence and absence of protest regard must, I believe, be had to the period of time when the events we are concerned with took place, to the region of the world to which they related, to the general political conditions existing in Asia at this period, to political and other activities of Western countries in Asia at the time and to the fact that of the two States concerned one was Asian, the other European. It would not, I think, be just to apply to the conduct of Siam in this period objective standards comparable to those which reasonably might today be or might then have been applied to highly developed European States.

There is a further general consideration of some significance. There can be little doubt that, at least in the early part of this century, Siam was apprehensive about the aspirations of France.

There is evidence of this.

In 1930, on the occasion of the visit of Prince Damrong to the Temple, which has figured so prominently in this case, he was accompanied by his daughter Princess Phun Phitsamai Diskul. In her statement which was placed before the Court she states the reason why her father did not ask the Thai Government to protest about the presence at the Temple of a French officer in full military uniform. She states:

"It was generally known at the time that we had only to give the French an excuse to seize more territory by protesting. Things had been like that since they came into the River Chao Phya with their gunboats and their seizure of Chanthaburi." [p 129]

No matter how unjustified this view may have been I am satisfied that it was not a view conjured up for the purposes of this case. It finds confirmation elsewhere.

In March 1907, in referring to the negotiations for the Treaty of 1907 then being conducted, Colonel Bernard, in a report of 19 March to the Governor-General of Indo-China, wrote:

"There is such mistrust of us in Siam and such dread of possible military action...",

and later in the same report:

"After five hours of discussion which the nervous state of the Siamese made painful, we concluded by reaching agreement...",

and on 17 June 1908, only two months before the map sheets of which Annex I is one were handed to Siam, Commandant Montguers, in his report to the Governor-General of Indo-China reveals the same apprehension on the part of Siam. The Commandant speaks of:

"Dispelling as far as possible the mistrust that is so deeply rooted in them."

This apprehension on the part of Siam as to France's attitude towards her is a factor which cannot be disregarded in evaluating Siam's conduct—her silence, her lack of protest, if protest might otherwise have been expected of her.
***
I have already given the reasons which have persuaded me to the opinion that there was in fact a delimitation of the northern frontier including the Dangrek. I have stated the nature of that delimitation and why Annex I fails to draw any probative force from it. If subsequent to its communication by France to Siam the line shown thereon acquired any probative force that could only occur (apart from any question of preclusion) by virtue of the two States entering into a new conventional arrangement giving rise to new mutual obligations between them.

The Court's approach is quite different and marks a point of departure between my views and those of the Court.

Judgment is based upon the conclusion that Siam, by her silence and failure to protest against Annex I and the line indicated on it within what is said to be a reasonable time after she received it, recognized, adopted, acquiesced in or acknowledged it as representing what is called the "outcome" of the work of delimitation of the frontier in the region of Preah Vihear and thereby conferred upon [p 130] it a binding character. Thus, the Court finds, it, in 1908-1909 became binding on Siam.

From the subsequent failure (on the part of Siam) to protest, the Court draws inferences to support its conclusion that Siam had in 1908-1909 recognized and acquiesced in Annex I with the character the Court has assigned to it.

The Judgment speaks of the contingency of a departure from the criterion of the watershed line stipulated in Article 1 of the Treaty. It however dismisses as irrelevant the question whether a departure may have occurred since, whatever was the nature of any inherent power of adaptation possessed by the Mixed Commission, it was it states certainly within the power of Siam in 1908-1909 to adopt any departures.

Either France or Siam was of course entitled to adopt or fail to adopt any attitude towards Annex I as it thought fit. The crucial question which, in my opinion, calls for an answer however is not whether Siam recognized, acknowledged, adopted or acquiesced in Annex I whatever the character assigned to that document may be; but whether the conduct of France and Siam ever gave rise to an implied conventional arrangement between the two States under which they mutually agreed to be bound by the frontier line shown on Annex I, whether it was or was not in conformity with the criterion of the watershed stipulated in the Treaty of 1904. This question, in my opinion, the Court leaves unanswered.

It is my view that unless the conduct of Thailand since 1908 has resulted in her being precluded from denying that the line on Annex I is the frontier line—a quite separate question which will be later considered—or unless there can be established a new and fresh conventional arrangement between the two States, any recognition by Siam of Annex I and of the line shown thereon cannot be conclusive against Thailand.

A State may of course recognize—or acquiesce in—any fact or situation either of law or fact and its intention to do so may be evidenced expressly or by implication. The recognition may become the source of a legal right or obligation to the extent to which it provides an essential element in the establishment of a legal right or obligation, as for example in preclusion or prescription. It may provide evidence of a fact or a state of facts, the probative value of which depends upon all the surrounding circumstances. It may afford aid in the interpretation of a document or conduct.

The act of recognition is not however a unilateral juridical act which of its own force precludes a State from thereafter challenging the fact or situation recognized. It may, depending upon the circumstances, provide strong, perhaps overwhelming, evidence of the truth of the fact or situation recognized; it may provide only evidence which is destroyed or modified by other evidence. Pre-[p 131]clusion—or, to use its Anglo-Saxon equivalent, estoppel—may however only occur where all the elements which constitute the principle of preclusion can be shown to exist.

There is a close affinity between prescription, preclusion, recognition, acquiescence and absence of protest. The principle of preclusion is however, in my view, quite distinct from the concept of recognition (or acquiescence), though the latter may, as any conduct may, go to establish either prescription or preclusion.

To accord to the concept of recognition by a State of a fact or situation, without more, the legal consequence of a preclusion not only finds, in my opinion, despite the views of certain writers, no authority as a principle of international law under Article 38 of the Statute of the Court, but provides an invitation to apply to the determination of a case in which recognition of a fact or of a situation is relied upon, considerations which are scarcely distinguishable from considerations ex aequo et bono.

The concepts of recognition and acquiescence are important elements of international law. They are not likely to add to their usefulness if pushed beyond their proper content.

In the present case any recognition by Siam of Annex I and the line of frontier shown thereon, or any acquiescence by Siam therein, is in my view of evidentiary value only.

Recognition by Siam of Annex I and the line of frontier thereon —if any were made—is of course evidence of an admission by Siam (and Thailand), which may be read against her to establish that there was in fact a decision of delimitation of the frontier on the Dangrek. It might perhaps be construed as an admission that that decision was correctly represented by the frontier line shown on Annex I.

Were any such admission the only evidence in this case it could well be conclusive. But it is not the only evidence. There is a great deal more. The task of the Court is to ascertain the true facts. It may in doing so be influenced by an admission established by the conduct of Siam. It cannot however be controlled by it if other evidence negatives or modifies or is inconsistent with the admission which a recognition may establish. The recognition is not conclusive.

In short, the evidentiary value of the recognition or acquiescence must be weighed against all other relevant evidence disclosed in the record.

When regard is had to other relevant evidence in the record, it will be seen that such admissions as may be spelt out of the conduct of Siam by the Court have little if any evidentiary value in the determination of this case. [p 132]

It is established that there never was any decision of the Mixed Commission agreeing to any line on any map or sketch. It is established that there never was any decision of delimitation by virtue of which the Mixed Commission, pursuant to an inherent power of adaptation of the correct line of the watershed, placed the Temple region for some special local or any other reason within Cambodian territory. It is established that there never was a decision to depart from the Treaty line of the watershed but, on the contrary, the evidence is that the Mixed Commission decided that that line should be adhered to. It is established that if there were a delimitation of the Dangrek it could only have been one to the effect that the frontier line should follow the line of the watershed, and if there were no decision of delimitation the frontier line remained the line of the watershed pursuant to the Treaty of 1904. It is established that Annex I does not follow the line of the watershed but, on the contrary, seriously departs from it at the critical area of the Temple region, and it will be established that the line on Annex I purports to show the line of the watershed and no other line.
***
It seems necessary to repeat that the line on Annex I had not been before the Mixed Commission when it came to an end. In fact, it could never have existed at all until after the Mixed Com-mission's last meeting.

The instructions of survey officers Captains Oum and Kerler are set forth in the Minutes of the Mixed Commission of 7 September 1906. Their task was to carry out a survey and nothing else.

It was contended on behalf of Cambodia that the task of the topographical officers—though they were in no way authorized themselves to delimit the frontier—included that of marking on the map the frontier line. Sometimes, it was suggested, this was done pursuant to a prior decision of the Mixed Commission; at other times the Mixed Commission, it was said, determined the line only after the map had been drawn up.

Even if the evidence gave any support to this contention it is clear that neither of these eventualities occurred. Captain Oum left to survey the Dangrek before the Mixed Commission had even started on its reconnaissance of the northern frontier, and the Mixed Commission held its final meeting over a month before he or Captain Kerler, who was surveying the region from the Great Lake to the Dangrek, reached Bangkok from their field operations.

Annex I never became part of the work of delimitation of the Mixed Commission and never accordingly could be said to have become an integral part of the treaty settlement. [p 133]

The conclusion of the Court based on recognition is, in my opinion, inconsistent with the established facts.
***
The conclusion of the Court that Annex I, as a consequence of Siam's recognition of it as representing the outcome of the work of delimitation is that it caused the map to enter the treaty settlement and thus to become an integral part of it, presents a difficulty which, in my view, goes to the heart of this case.

It is not necessary for me to express any opinion on whether, or to what extent, this recognition could cause the map to enter the treaty settlement. The point to which I desire to direct attention is that it follows from the Court's conclusion that Annex 1 is to be treated as if there had been a decision of the Mixed Commission that the frontier on the Dangrek should be delimited in accordance with the line shown thereon.

It would then fall for determination whether it was a delimitation established on the basis of the criterion laid down in Article 1 of the Treaty of 1904 which was that the frontier line should follow the line of the watershed. If the delimitation were not established on that basis, the line on Annex I could not, in my opinion, have any probative value; it could have no binding force upon either Siam or France.

The Court seeks to resolve the difficulty on the basis, not of a new conventional agreement—since none is shown or could be shown to exist—but on the basis of treaty interpretation.

The line shown on Annex I is beyond doubt not the line of the watershed, in particular it is not that line in the critical vicinity of the Temple. On the basis that Annex I is, or represents, a delimi-tation of the Dangrek by the Mixed Commission it is evident that the line in Annex I is not established in accordance with the criterion laid down in the Treaty.

The Court however does not see it this way. Basing its reasoning on a proposition that the two States, despite the clear provisions of Article 1, did not attach any special importance to the line of the watershed but were concerned with what is described as the overriding importance of adhering to a map line in the interests of finality—a conflict between the line in Annex I and Article 1 of the Treaty of 1904 is resolved as a matter of treaty interpretation in favour of the line on the map sheet.

I do not agree either with the proposition on which the Court bases its reasoning or with its reasoning. I cannot agree that a derogation from what is provided in the Treaty, namely that the frontier should follow the line of the watershed, can be disposed of [p 134] in this manner by treating the map, the line on which was to conform to the Treaty, as in law overriding it.

This, in my view, is not treaty interpretation. It amounts, in my opinion, to redrafting the Treaty of 1904 in accordance with a presumed intention of the two States, an intention indeed which is not to be found within the terms of the Treaty itself nor, in my view, elsewhere in the evidence; a presumed intention which is moreover quite inconsistent with the plain terms, not only of Article 1 of the Treaty, but as well with Article 3 thereof which provided that the work of the Mixed Commission had as its object "the frontier determined by Article I".

Moreover, it hardly seems possible even as a matter of treaty interpretation to pronounce in favour of the line of Annex I in the absence of a determination of the extent to which Annex I does or does not in fact conform to the stipulations contained in Article 1 of the Treaty itself.

Finally, if the record establishes, as I believe it does, that the Dangrek was in fact delimited by the Mixed Commission and that the decision was that the frontier should follow the line of the watershed there would be a conflict between the line on Annex I and the decision of the Mixed Commission. This conflict could not be resolved by the method of treaty interpretation to which the Court has had resort. The decision of the Mixed Commission that the frontier line should be the line of the watershed destroys the foundation on which the Court's reasoning is based. In any case, there could be no doubt that the decision of the Mixed Commission, that the frontier line was to follow the line of the watershed, must prevail over any map line which purports but fails to reflect that decision.
***
There are further difficulties in the way of the thesis which the Judgment expounds. Annex I and the ten map sheets accompanying it were delivered to Thailand and received by the latter at the same time and in the same circumstances.

If Annex I became part of the treaty settlement of 1904 by virtue of the recognition found by the Court, so did they all. Yet, between the time when the Mixed Commission under the 1904 Treaty held its last meeting and ceased to function, and the end of March 1907, France had entered into the Treaty and Protocol of 1907.

Six of the eleven maps related to the frontier region between Siam and Cambodia. The frontier line on three of them covering the regions between the Great Lake and the sea to the south no longer existed as frontier lines. Not only did they not exist, but the whole region covered by these map sheets—issued in 1908—were [p 135] no longer in Thai territory. There seems little purpose in Siam having adopted or recognized them.

Of the three remaining map sheets, namely those which covered the northern frontier, two covered the region of the Pnom Padang; one of which also covered part of that mountain range and a section of the eastern part of the Dangrek. It would not I think, as a matter of treaty interpretation, be possible to reconcile the frontier line shown on these two maps, in so far as they relate to the region of the Pnom Padang, with the frontier line stipulated in the Treaty of 1907.

Under this Treaty, the line of the frontier on that range of mountains as far as the Mekong no longer followed the crest, as the decision of the Mixed Commission of. 18 January indicates it should do in accordance with the provisions of the 1904 Treaty, but the line of the watershed. Article I of the Protocol of 1907 was the law which governed the two States.

This is also the position with regard to the Dangrek. After the Mixed Commission under the 1904 Treaty had ceased to function, Article I of the Protocol of the Treaty of 1907 stipulated in clear and unambiguous terms that the frontier line on the Dangrek should be that of the watershed. The line on Annex I cannot as a matter of treaty interpretation be reconciled with the 1907 Treaty. The Treaty must prevail.

Unless therefore France and Siam thereafter entered into a new conventional arrangement that the line on Annex I was to become binding upon them irrespective of whether it did or did not answer to the criterion of the line of the watershed, it is the watershed line of the 1907 Treaty on the Dangrek which must prevail.

That the law governing the two States subsequent to 1907 was the treaty line defined in Article I of the Protocol of 1907 was acknowledged by France in her diplomatic note of 1949 to Siam, in which she said in specific and unmistakable terms that the frontier line between herself and Siam was that stated in the 1907 Protocol, namely the watershed which continued to be the frontier line between the two States. This is the same position which Cambodia took up in its own diplomatic note of 1954.
***
I turn now to the question whether the evidence establishes any consensual agreement between France and Siam in relation to the frontier line shown on Annex I.

An agreement between the two States could have taken a number of forms. Neither was subject to the limitations of authority which the Treaty of 1904 imposed upon the Mixed Commission. Each State had plenary powers. Either could, had its mind been directed to the matter, have sought modification of the line shown [p 136] on Annex I or refused to agree to it. The two States could have agreed that, notwithstanding the terms of any treaty between them, having regard to certain political or other considerations, the line should be altered, which was precisely what the two Governments in 1905 did agree to do outside the terms of the Treaty of 1904 in respect of the region of Kratt on the sea south of the Great Lake. The two States could have agreed to accept the line on Annex I as representing the line of the watershed whether it did or did not conform with that line. They could have agreed that the line on Annex I should be deemed to have been a delimitation by the Mixed Commission under the 1904 Treaty whether there had or had not been such a delimitation. They could have expressed their agreement in the form of a new convention—they could, but in my view most improbably, have left their agreement to be evidenced by their conduct.

The matter was at large.

Whatever agreement were reached, it would have involved a new or fresh obligation undertaken by each State in relation to the other. Whether in the events which happened any such agreement was made—and if so what was the nature and content of it—depends upon whether any may be implied from the evidence.

The Judgment directs its consideration almost exclusively to an examination and criticism of Thailand's conduct of silence and non-protest. There is however another side of the picture.

***
Criticism may indeed be directed against Thailand and inferences adverse to her drawn from the fact that on a number of occasions over the years since 1908-1909 she remained silent on the map sheets. The fact however is that France herself innocently, but none the less to a major extent, directly contributed to the very conduct of Thailand that Cambodia has sought to rely upon, and the Court thinks is of such significance. For it was the act of France in presenting the map sheet Annex I which purported to show a frontier line drawn correctly to represent the line of the watershed— whether based upon a decision of the Mixed Commission or upon the Treaty line—that induced Thailand to believe that the line shown on Annex I had been correctly drawn.

My own approach to the facts, as well as to the legal issues involved, differs from that of the Court. I take another view of the facts and my enquiry is directed to a different end, namely to determining whether there was a consensual arrangement between France and Siam that the line on Annex I was to be the established frontier between the two States. [p 137]

***
A few general observations should first be made.
In the first place, the concentration of attention on the small area of the Temple as shown at Annex I tends to shut out of view or obscure other and more important facts. It is of course true that although the Court has been requested by Cambodia to declare that the line shown on Annex I is the line of the frontier in the region covered by that map, it is only called upon to pronounce on the claim as stated in the Application, namely whether sovereignty over the Temple is vested in Cambodia. But this it cannot do except by first arriving at a conclusion one way or the other on whether the frontier line on Annex I as a line which legally is binding on the two States.

This being the essential step in reaching a decision, little purpose, it seems to me, is served by stressing, indeed I think overstressing, the fact that if you look at the map sheet Annex I it will be seen the Temple lies on the Cambodian side of the frontier line. That is evident. It becomes perhaps more insistently pressed upon the eye the more one looks at the comparatively small part of a large map sheet.

It is easy to fall into the error of thinking that the Temple and who was to obtain sovereignty over the Temple was the principal or the prime concern of the two States in 1908-1909 and that, when Thailand received the maps, almost the first thing which she might be expected to do would be to see whether sovereignty over the Temple had been accorded to her. All this, I think, bears little relation to the realities.

Quite apart from the fact that the Temple was not of any great significance to either State in 1908-1909—it never found a mention in any of the voluminous correspondence of Colonel Bernard— what the two States were concerned with under the 1904 Treaty was the delimitation of frontiers of considerable length. In so far as one part of the frontier was concerned, namely the Dangrek, the line was to be the line of the watershed. If that line placed the Temple or any other part of the territory between the two States one side or the other, that was the result of the Treaty and could hardly be the subject of protest.

France, in whose technical capacity accurately to construct the map of the frontier regions Siam reposed confidence, prepared the map sheets. That Siam did so repose confidence in France's technical capacity to do this is beyond dispute. France, by preparing the map sheet Annex I, represented in my view, when it was delivered by her to Siam, that it was correctly drawn and that the frontier line shown thereon was in accordance with the decision of the Mixed Commission or, if there was no such decision, was in accordance with the Treaty line. In particular, she unequivocally represented that [p 138] the frontier line so depicted was the true line of the watershed.

In these circumstances alone, on any approach to this case I would find little justification in demanding from Thailand that she should, within some time regarded as reasonable after she received Annex I, have herself ascertained whether the line represented by France as correctly showing the line of the watershed was accurate or not and that, having failed to protest, it should be concluded against her that she acknowledged the line was correct whether she in fact knew it was or not—and should be held bound by it.

A second observation of a general character throws light upon the circumstances in which the Parties were placed at the relevant period of time.
Prior to 1904 Thailand exercised sovereignty over the whole area of the Dangrek right to the cliff face. Such acts of administration as were, prior to 1904, effected by her in the area were, I am satisfied, continued on thereafter. Certainly, until 1949, when the present dispute about the Temple first asserted itself, these acts of administration were of a sporadic character. They were, however, less sporadic and covered a larger part of governmental activity than any acts exercised by France. Although much has been heard in this case about the importance of final and settled frontiers, apart from the one incident of Prince Damrong's visit to the Temple, neither State appears to have been aware of what the other was doing. It is significant that the Governor of the Cambodian province adjacent to the Temple had not the slightest idea where the frontier lines were. All he appeared to know was that the Temple was, so he claimed, within Cambodian territory.

The reason is not hard to find. The Temple ruins, which were the subject of a number of scattered visits by archaeologists, were allowed to submit to the years and the elements. The region to the immediate north of the escarpment dominating the Cambodian plains was forbidding and remained so. A few people apparently from time to time eked out an existence there. The whole district along the escarpment on the Dangrek was covered with sparse forest and stunted trees and was, in Colonel Bernard's view, "despairingly monotonous". After the summer rains it swarmed with game. In the dry season "there could not be", he says, "a more desolate landscape". The rivers were dry and "water was only to be found in loathsome pools where all the wild animals come to drink".

It was, in short, territory, certainly not in the early part of this century, of any great consequence to France or Thailand. The picture of France or Thailand at this period of time being specially [p 139] interested in having an agreed line on a map to indicate where the frontier was—irrespective of whether it was or was not the line of the watershed—or in knowing which side of that line the Temple fell does not strike me as a real one. It was indeed, in my opinion, only much later that the limited region near the Temple, for archaeological and military reasons, acquired any real significance on the political level for either State.

***
The issue to be decided is whether the record establishes an agreement between France and Siam that Annex I and the frontier line indicated thereon would be accorded by each of them conventional force. The proper enquiry under this issue is whether in 1908 or thereabouts the conduct of the two States establishes a common intention to contract mutual obligations and rights in relation to the frontier line shown on that map sheet and, if so, what was the nature of the agreement to which their common intention gave expression.

The right of entering into an international engagement is an attribute of State sovereignty. That a State has entered into such an engagement may not lightly be inferred from conduct.

Conduct may, however, be such that it may be inferred that two or more States have entered into an international engagement. The intention of a State to enter into such an engagement may however only be inferred from facts which conclusively establish it.

The evidence in this case falls far short of such a test.
In the normal course of events, had there been any intention on the part of either of the two States to enter into an international engagement in relation to the line on Annex I, it might be expected that some trace of that intention would have been left, if not in written form then at least by some unequivocal overt act on its part indicating that intention. There is none. It can scarcely be contended that the act of France in delivering to Siam copies of a map which were at the same time delivered by her to third parties evidenced any intention on her part to enter into an international engagement. There is nought save silence on her part; silence unbroken for forty years. When, in 1949, at the time she despatched to Thailand a diplomatic note alleging infringement of her territorial sovereignty in the region of the Temple, she broke the silence, it was not to suggest that any agreement had arisen in 1908-1909, nor indeed to suggest that Thailand had by her conduct in those years or since recognized the line in Annex I as being the frontier line. It was to say something which, in my view, is inconsistent with either suggestion. [p 140]

Nor has there been left any trace of any intention on Thailand's part to enter into an international engagement. Here too there is silence over the decades.

The reason why no trace of any intention on the part of either State to enter into any international engagement is to be found is, I think, evident enough. There just was no such intention.

France prepared the map sheets primarily, as I think was the case, for her own purposes, and partly in response to the request of Siam made in November 1905 that a map of the frontier regions should be drawn up by French officers.

The printing of the map sheets did not follow as a matter of course on any work of the Mixed Commission. The map sheets were indeed not directly the necessary consequence or the outcome of the work of delimitation of the Treaty of 1904. Long after the Mixed Commission had ceased to function, authority to print them had, as has been noted, first to be obtained from the French Minister for the Colonies. Moreover, the map sheets, as even a casual look at them reveals, though based on work done by officers attached to the French Commission during the occasion of the work of the Mixed Commission, was not the work of the Mixed Commission. The major part of the detail appearing thereon is wholly unconnected with any work of delimitation.

It is abundantly evident from the report of his mission by Colonel Bernard to the French Minister of the Colonies of 14 April 1908, in which he reviewed the studies the French Commission "had to carry out", that the French Delimitation Commission was, during the course of the operations of the Mixed Commissicn, engaged in work which went far beyond the work of delimiting frontiers. The work of the French Commission included "ethnographical research and cartographical work". Attached to his report, in addition to all the Minutes of the Mixed Commission, were a number of reports by different officers attached to his Mission including one, for example, on the highway from Bangkok to Xieng Khong in the far north of Siam. The description of the reports suggests that the work of the French Commission, reflected in large measure in the various map sheets, had been by no means limited to work of delimitation called for by the Treaty of 1904.
It appears reasonably evident that whether Siam had or had not requested that French officers should execute maps of the frontier region, or however their request had originated, that the French Commission intended to prepare these maps in any case.

Moreover, the French Minister of the Colonies, who authorised the printing and publication of the maps, or his departmental officers, were acquainted with the contents of the Minutes of the Mixed Commission and accordingly knew from them and the many [p 141] reports of Colonel Bernard precisely what decisions had been taken by that Commission.

France knew what the record disclosed and they rested content with the record, confident in the reliability of their own topographers and cartographers.

If, however, they believed that some confirmation was necessary, to establish a decision of the Mixed Commission which was not recorded or not sufficiently recorded in the Minutes, it might reasonably be expected they would have specifically raised the matter and not remained silent about it. On the other hand, if they knew that there was no decision of the Mixed Commission delimiting the Dangrek they would certainly know there was no decision to depart from the line of the watershed and that accordingly the frontier was governed by the line of the watershed sti-pulated in the Treaty and Protocol of 1907. Whichever way the matter is viewed they knew it was the line of the watershed. The frontier line shown on Annex I is not consistent with any other hypothesis.

The examination of Annex I serves, in my view, to establish this. It shows the contours of the terrain on the Dangrek. It is, I think, evident, even to one not expert in the reading of contour lines, that the frontier line shown on Annex I over its whole length is directly connected with and based on these lines. It would appear probable on the face of Annex I that the frontier line was drawn so as to follow the line of the watershed as indicated by the various contours of the terrain shown thereon.

That this was in fact so is borne out, certainly in the critical region surrounding the Temple, by the evidence of Professor Schermerhorn who stated that the frontier line shown on Annex I was drawn up by constructing the watershed line in accordance with the contour lines shown. If the contour lines were correct the line of the watershed would have been correct. As, however, has been shown, the contour lines were not correct.

France accordingly knew Annex I represented the line of the watershed. If it was correctly drawn, as she was quite certain was so, there was no need for any further agreement between herself and Siam.

Moreover France, I am satisfied, was aware that Siam did not have the technological capacity to carry out a check survey. She certainly knew Siam had no means of knowing whether the frontier line on Annex I was correct or not and she knew that Siam was relying on her. It seems impossible in those circumstances to imagine she could ever have had any contractual intention in sending the map sheet to Siam or that she should think that Siam had any such intention. [p 142]


Furthermore, France knew when she delivered the map to Siam that certain of the map sheets were of no possible practical value to Siam as a consequence of the Treaty of 1907.

What applies to Annex I must apply also to all the map sheets. There is no room for a contract being implied in relation only to Annex I. If any conventional agreement is to be implied it must be one which relates to all the map sheets which were the constituents of the one map. The fact that certain of the map sheets had no longer any frontier significance goes to confirm that France never had the intention of creating any conventional arrangement between herself and Siam.

Finally, when in 1949 France protested by diplomatic note against the stationing by Thailand of guards at the Temple, not a word is said about any conventional arrangement having been made between herself and Siam. In her diplomatic note of 9 May of that year France set out with particularity the grounds on which it contended that sovereignty in the Temple was vested in her.

The note disclosed that France relied upon the Protocol annexed to the Treaty of 23 March 1907. It stated that the frontier was, and continued to be, that defined by Article I of the Protocol, namely the line of the watershed. It claimed that Annex I showed in detail the frontier line so defined and that the map was drawn up in 1904-1905 (sic) under the direction of Colonel Bernard and that the line shown on that map was the line referred to in Article I of the Protocol as "in conformity with the line adopted by the preceding Commission of Delimitation on 18th January, 1907". This is the same ground on which Cambodia put forward her claim to sovereignty in the diplomatic note in 1954. It is the same ground which was put forward by Cambodia in her Application and Memorial.

At no time, until after these proceedings commenced, was there any suggestion of any implied agreement arising out of conduct. France's claim for sovereignty, and later Cambodia's, rested solely on express agreement.

No implied agreement has been made out.
***
I come now to the question whether Thailand as a result of her conduct in 1908 and since is precluded from contesting that the line shown on the frontier in Annex I is the established frontier.
***
Whether Thailand is precluded from contesting the frontier line shown on Annex I cannot be answered until the essential legal elements which constitute preclusion are ascertained. [p 143]

The words "adoption", "acceptance", "acquiescence" and "recognition" which, in the course of the proceedings have been so often used, are apt I think to cloud legal principles unless it is quite clear in what sense they are being used.

These words are principally, concerned with factual situations to which certain general principles of international law may apply and in so doing operate so as to affect legal rights and obligations as between States.

Moreover, phrases such as "a party may not blow hot and cold" or "allegans contraria non est audiendus" and others to the same effect do not, in my view, express general principles of international law. They are but a convenient and compendious way in which, in a general sense, the reasons which underlie certain legal principles and rules may be described.

Any situation may, as has been stated, be the subject of an act of recognition or may be acquiesced in. A situation so recognized or accepted may, and usually does, acquire evidential value and in certain circumstances may attract or produce legal consequences creating, affecting, or changing a legal relationship between States.

There is however, in my view, no foundation in international law for the proposition that an act of recognition by a State of or acquiescence by a state in a situation of fact or law is a unilateral juridical act which, operating of its own force, has the legal consequence of precluding a party giving or making it from thereafter challenging the situation which is the subject of recognition or acquiescence.

The cases of Legal Status of Eastern Greenland (Series A/B No. 53), Status of South West Africa (I.C.J. 1950) and Arbitral Award by the King of Spain (I.C.J, 1960) do not support, in my view, this proposition. To claim that they do is to read into their facts law which is not there.

***
The principle of preclusion is a bénéficient and powerful instrument of substantive international law. Based as it is upon the necessity for good faith between States in their relations one with another, it is not to be hedged in by artificial rules. It should not however be permitted to become so indefinite as to acquire the somewhat formless content of a maxim. And since the principle, when it is applicable to any given set of facts, substitutes relative truth for the judicial search for the truth, it should be applied with caution.

In my opinion the principle operates to prevent a State contesting before the Court a situation contrary to a clear and unequivocal representation previously made by it to another State, either ex-[p144] pressly or impliedly, on which representation the other State was, in the circumstances, entitled to rely and in fact did rely, and as a result that other State has been prejudiced or the State making it has secured some benefit or advantage for itself.

Unless the elements so stated can, in any particular case, be shown to exist, the principle has no application.

The Arbitral Award of the King of Spain (I.C.J, 1960) neither extended nor cut down this principle. It applied it. All the constituent elements were, in my view, established in that case.

Whether the principle applies to the present case is an issue of fact and law.

***
The question of preclusion was not raised by Cambodia in her Application, but during the course of the oral proceedings. It occupied a distinctly subordinate place in the presentation of Cam-bodia's claim.
If a State claims it has been prejudiced by the conduct of another State in circumstances which prevent that other State from legally contesting what otherwise is an important fact or situation and fails to raise the issue of preclusion in any way until very late in the day, that is a circumstance which cannot be disregarded. It bears upon whether there is any substance in the claim.

***
I greatly doubt whether any of the elements of preclusion have been established by Cambodia. Even were it established that Thailand's conduct did amount to some clear and unequivocal representation, and that France relied upon it and was entitled so to do, I do not think there is any evidence that France—or Cambodia— suffered any prejudice. Certainly no piece of evidence so far as I can recall was ever presented which could establish that either State did.

Nor is it apparent what benefit Thailand can be said to have obtained as a result of her absence of protest.

I do not find it, however, necessary to examine these matters.

In my opinion the evidence quite fails to establish any clear and unequivocal representation on the part of Thailand.

Moreover, I am satisfied that France never acted upon the faith of any representation which may be inferred from Thailand's conduct.

It is not sufficient to assert that she did, the evidence must establish it. The burden of proof lies upon Cambodia and, in my view, she has failed to discharge the burden. [p 145]

France never in any manner, over a period of 50 years, suggested that she had relied upon any conduct on Siam's part. Indeed, her diplomatic note of 9 May 1949 before referred to, gives not the slightest suggestion that she ever had.

The explanation is, I think, evident. France did not rely upon any conduct of Thailand in relation to Annex I. On the contrary, she relied solely upon the accuracy of the surveys and calculations of her own topographical officers and the map sheets drawn up by her own cartographers based upon those surveys and calculations. She acted not on the faith of Thailand's silence or other conduct, but upon the faith she reposed in the competence of the officers who established Annex I. She was quite confident that the question of the frontier between herself and Siam was governed by Article I of the Protocol of 1907 and that Annex I was correct. Moreover, she mistakenly believed, as at all times did Cambodia, that the reference in that Article to "the line (tracé) adopted by the preceding Commission of Delimitation on 18th January, 1907" was a reference to Annex I and the line depicted thereon and thus was formally confirmed by that Protocol.

It was indeed not Thailand's reaction or attitude to the map sheets which determined France's course of action. On the contrary, as France knew, it was Siam who relied upon her in the drawing up of maps. In a letter of March 1909 the French Minister in Siam, reporting to the French Foreign Minister on the work of the Transcription Committee, reveals clearly enough that it was the policy of France that Siam should continue to rely upon her in matters touching the drawing up of maps. French interest in the Transcription Committee was not limited to its work. There was, the French Minister writes, also "an ultimate aim ... entertained from the outset". The objective was "to persuade the Siamese to embark on a course that is likely to lead them to the goal we have in view, that is to say, to cause them, at a later stage, to appeal invariably for our help for the purpose of drawing up a general map of Siam...".

For my part, I am satisfied that France, except in terms of her general political policy and of attracting Siam to a closer dependence upon her, had not the slightest interest in how Siam reacted to Annex I or any other of the map sheets; there was no reaction she could have expected. She knew the extent to which Siam was dependent upon her in the construction of the maps and she wanted that sense of dependence to remain. I am quite unimpressed by the contention put forward late in the day—a contention which there is not one piece of direct evidence to support—that France relied upon Siam's acceptance of Annex I. France produced the map sheets, including Annex I, was satisfied they were correctly drawn up and required no confirmation—and remained at all times sati-[p146]fied they were correct. On that basis, and that basis alone, France conducted herself thenceforth.

In my opinion, Thailand is not precluded from alleging that the line on Annex I is not the frontier line.
***
I regret exceedingly that I have found it necessary to express my views at such length. This case, important though it is for the two States directly concerned, has however a significance which extends beyond the confines of the present litigation.

Whether the Mixed Commission did or did not delimit the Dangrek, the truth, in my opinion, is that the frontier line on that mountain range is today the line of the watershed.

The Court however has upheld a frontier line which is not the line of the watershed, one which in the critical area of the Temple is an entirely different one.

This finds its justification in the application of the concepts of recognition or acquiescence.

With profound respect for the Court, I am obliged to say that in my judgment, as a result of a misapplication of these concepts and an inadmissible extension of them, territory, the sovereignty in which, both by treaty and by the decision of the body appointed under treaty to determine the frontier line, is Thailand's, now becomes vested in Cambodia.

(Signed) Percy Spender.