Case Concerning the Temple of Preah Vihear (Cambodia v. Thailand)Author(s): Covey OliverSource: The American Journal of International Law, Vol. 56, No. 4 (Oct., 1962), pp. 1033-1053Published by: American Society of International LawStable URL: http://www.jstor.org/stable/2195943 .Accessed: 22/03/2011 21:48Your use of the JSTOR archive indicates your acceptance of JSTOR's Terms and Conditions of Use, available at .http://www.jstor.org/page/info/about/policies/terms.jsp. JSTOR's Terms and Conditions of Use provides, in part, that unlessyou have obtained prior permission, you may not download an entire issue of a journal or multiple copies of articles, and youmay use content in the JSTOR archive only for your personal, non-commercial use.Please contact the publisher regarding any further use of this work. Publisher contact information may be obtained at .http://www.jstor.org/action/showPublisher?publisherCode=asil. .Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printedpage of such transmission.JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range ofcontent in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new formsof scholarship. For more information about JSTOR, please contact support@jstor.org.American Society of International Law is collaborating with JSTOR to digitize, preserve and extend access toThe American Journal of International Law.http://www.jstor.orgJUDICIALDECISIONS BY COVEYOLIVER Of the Board of Editors Territorialtsovereignty-treaty interpretation-maps-preclusion or estoppel CASECONCERNINGTHETEMPLEOFPREAHVIHEAR(CAMBODIAV. THAILAND),MERITS.I.C.J. Reports,1962, p. 6.1 InternationalCourt of Justice.2 Judgmentof June 15, 1962. In its Judgmentof 26 May 1961, by which it upheld its jurisdictionto adjudicate upon the dispute submittedto it by the Application filedby the Governmentof Cambodia on 6 October 1959, the Court described in the followingterms the subject of the dispute: "Inthe present case, Cambodia alleges a violation on the part of Thailand of Cambodia's territorialsovereigntyover the region of the Temple of Preah Vihear and its precincts.Thailand replies by af- firmingthat the area in question lies on the Thai side of the common frontierbetween the two countries,and is under the sovereigntyof Thailand.This is a dispute about territorialsovereignty." Accordingly,the subject of the dispute submittedto the Court is confined to adifferenceof view about sovereigntyover the region of the Temple of Preah Vihear.To decide this question of territorialsovereignty,the Court must have regard to the frontierline betweenthe two States in this sector.Maps have been-submittedto it and various considerationshave been advanced in this connection. The Court will have regard to each of these only to such extentas it may findin themreasons for the decision it has to give in order to settle the sole dispute submittedto it, the subject of which has just been stated. The Temple of Preah Vihear is an ancient sanctuaryand shrinesituated on the borders of Thailand andCambodia.Although now partially in ruins,this Temple has considerableartisticand archaeologicalinterest,and is still used as aplace of pilgrimage.It stands on a promontoryof the same name, belongingto the eastern sector of the Dangrek range of moun- tains which,in ageneral way, constitutesthe boundary between the two countriesin this region-Cambodia to the south and Thailand to the north. Considerableportions of this range consist of a high cliff-likeescarpment rising abruptlyabove the Cambodian plain.This is the situationat Preah I Excerptedtext of opinionpreparedby Wm. W. Bishop, Jr. 2 Composedfor this case of PresidentWiniarski;Vice PresidentAlfaro; and Judges Basdevant,Badawi, MorenoQuintana,WellingtonKoo, Sir Percy Spender,Sir Gerald Fitzmaurice,Koretsky,Tanaka, Bustamantey Rivero,and Morelli. 1033 1034THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 Vihear itself,wherethe main Temple buildings stand in the apex of a tri- angular piece of high ground jutting out into the plain.From the edge of the escarpment,the general inclinationof the ground in the northerlydi- rectionis downwardsto the Nam Moun river,which is in Thailand. It will be apparent fromthe descriptionjust given that a frontierline whichran along the edge of the escarpment,or whichat any rate ran to the south and east of the Temple area, would leave this areain Thailand; whereas a line runningto the north,or to the northand west,would place it in Cambodia. Thailand has urged that the edge of this escarpmentconstitutesthe natu- ral and obvious line for a frontierin this region.In support of this view Thailand has referredto the documentaryevidence indicativeof the desire of the Parties to establish frontierswhich would not only be "natural", but visible and unmistakable-such as rivers,mountainranges, and hence escarpments,wherethey exist. The desire of the Parties for a natural and visible frontiercould have been met by almostany line whichfolloweda recognizablecourse along the main chain of the Dangrek range.It could have been a crestline, a water- shed line or an escarpmentline (where an escarpmentexisted,whichwas far fromalways being the case).As will be seen presently,the Parties pro- vided for a watershedline.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 crestor escarpment. They cannot there- fore be presumedto have intended that, whereveran escarpmentexisted, the frontiermustlie along it, irrespectiveof all otherconsiderations. The Parties have also relied on otherargumentsof a physical,historical, religious and archaeological character,but the Court is unable to regard themas legally decisive. Asconcernsthe burden of proof, it must be pointed out that though, fromthe formalstandpoint,Cambodia is the plaintiff,having institutedthe proceedings,Thailand also is aclaimant because of the claim which was presentedby her in the second Submission of the Counter-Memorialand which relates to the sovereigntyover the same piece of territory. Both Cambodia and Thailand base theirrespectiveclaims on a series of facts and contentionswhich are asserted or put forwardby one Party or the other. The burden of proof in respect of these will of course lie on the Party as- sertingor putting them forward. Until Cambodia attained her independence in1953 she waspart of French Indo-China, and her foreign relations-like those of the rest of French Indo-China-were conducted by France as the protectingPower. It is commonground between the Parties that the present dispute has its fonset origoin the boundary settlementsmade in the period 1904-1908, betweenFrance and Siam (as Thailand was then called) and, in particular, that the sovereigntyover Preah Vihear depends upon a boundary treaty dated 13 February 1904, and upon events subsequent to that date.The Court is thereforenot called upon to go into the situation that existed betweenthe Parties prior to the Treaty of 1904. 1962]JUDICIALDECISIONS1035 The relevantprovisionsof the Treaty of 13 February 1904, which regu- lated interalia the frontierin the easternDangrek region,were as follows: [Translationrby the Registry] "Article 1 The frontierbetweenSiam and Cambodia starts,on the left shore of the Great Lake, fromthe mouth of the river Stung Roluos, it follows the parallel fromthat point in an easterlydirectionuntil it meets the river Prek Kompong Tiam, then, turningnorthwards,it mergeswith the meridian from that meeting-pointas far as the Pnom DangRek 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 otherhand, and joins the Pnom Padang chain the crestof which it followseastwardsas far as the Mekong. Upstreamfromthat point, the Mekong remains the frontierof the Kingdom of Siam, in accordancewith Article 1 of the Treaty of 3 October1893." "Article 3 There shall be a delimitationof the frontiersbetweenthe Kingdom of Siam and the territoriesmaking up French Indo-China.This de- limitationwill be carried out by Mixed Commissionscomposedof offi- cers appointed by the two contractingcountries. The work will relate to the frontierdeterminedby Articles 1 and 2, and the region lying betweenthe Great Lake and the sea." It will be seen, in the firstplace, that these articles make no mentionof Preah Vihear as such. It is for this reason that the Court can only give a decision as to the sovereigntyover the Temple area after having examined what the frontierline is.Secondly, whereas the general character of the frontierestablishedby Article 1 was, along the Dangrek range, to be a watershedline, the exact course of this frontierwas, by virtue of Article 3, to bedelimited by aFranco-Siamese MixedCommission. Itistobe observed,moreover,that what had to be delimitedwas "the frontiers"be- tween Siam and French Indo-China; and although this delimitationhad, prima facie, to be carried out by referenceto the criterionindicated in Article 1, the purpose of it was to establishthe actual line of the frontier. In consequence,the line of the frontierwould, to all intentsand purposes, be the line resultingfromthe work of delimitation,unless the delimitation were shownto be invalid. Indue course, aMixed Commissioncomposed of French and Siamese memberswas set up, charged with the task of delimitingthe frontierin various districts,including the eastern sector of the Dangrek range in which Preah Vihear is situated.This Mixed Commissionwas composedof two sections,one French and one Siamese, sittingtogether-one consisting of French topographicaland administrativeofficersunder a French presi- dent,and the otherof Siamese membersunder a Siamese president. So far as the frontierin the Dangrek range was concerned,the task of this Mixed Commissionwas confinedto the easternsector (roughlyeast of the Pass of Kel)in whichPreah Vihear is situated. At this time the westernsectorof the Dangrek lay whollyin Thailand.It was only when a furtherboundary settlement,under a treatydated 23 March 1907, broughtwithin Cambodia 1036THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 various districtsabutting on the western Dangrek sector,that the latter became a frontierregion.The task of delimitingthe frontierin this latter region was given to asecond Mixed Commissionset upunder the 1907 Treaty. The Mixed Commissionset up under the Treaty of 1904 held its first meetingin January1905, but did not reach that part of its operationsthat concernedthe frontieralong the eastern sector of the Dangrek range until December 1906, althoughit appears fromthe minutesof the Commission's meetingof 2 December 1906 that one of the French membersof the Com- mission,Captain Tixier, had passed along the Dangrek in February 1905. At the meetingof 2 December1906, held at Angkor-Wat,it was agreed that the Commissionshould ascend the Dangrek fromthe Cambodian plain by the Pass of Kel, whichlies westwardsof Preah Vihear, and travel eastwards along the range by the same route (or along the same line)as had been reconnoitredby Captain Tixier in 1905 ("letrace qu'areconnu . . . le capitaine Tixier").It was stated that all the necessaryreconnaissancebe- tweenthis route and the crestline (to which it ran roughlyparallel) could be carried out by this method,since the route was, at the most,only ten to fifteenkilometresfromthe crest,on the Siamese side.It has not been con- tested that the Presidents of the French and Siamese sectionsof the Com- mission,as representingit, 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 meetingof 2 December 1906, it was also agreed that an- other of the membersof the French section of the Commission,Captain Oum, should, startingat 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 Commissionfully intendedto delimitthe frontierin this sector of the Dangrek and that it took all the necessary steps to put the work of delimitationin hand.The work must have been accomplished,for at the end of January 1907 the French Ministerat Bang- kok reportedto the Ministerof Foreign Affairsin Paris that he had been formallynotifiedby the Presidentof the French sectionof the Mixed Com- missionthat the whole work of delimitationhad been finishedwithoutinci- dent, and that the frontierline had been definitelyestablished,except in the region of Siem Reap.Furthermore,in a report on the whole work of delimitation,dated 20 February 1907, destinedfor his own Government,the Presidentsaid that: "Allalong the Dangrek and as far as the Mekong,the fixingof the frontiercould not have involved any difficulty." Mention may also be made of a map produced by Thailand, recentlyprepared by the Royal ThaiSurvey Department, Bangkok, tracing in the Dangrek the "Route followedby the Mixed Commissionof 1904". It seems clear thereforethat a frontierwas surveyedand fixed; but the question is what was that frontier(in particular in the region of Preah Vihear), by whomwas it fixed,in what way, and upon whose instructions? Tlhedifficultyin answeringthese questions lies in the fact that, after the 1962]JUDICIALDECISIONS1037 minutesof the meetingof the First Commissionon 2 December 1906, there is no furtherreferencewhatever,in any minutesof later meetings,to the question of the frontierin the Dangrek region. Itappears that at about this time the Commissionhadin substance finishedits work on the ground and was awaiting the reports and provi- sional maps of the surveyofficers(Captain Oum and others).These reports and maps would not be available until February-March1907 when,in nor- mal circumstances,another meeting of the Commissionwould have been held to considerthem.It appears that a meetinghad been provisionally fixedfor 8 March.That it was certainlythe intentionto call one, can be seen froma despatchfromthe French Ministerin Bangkok to the Minister of Foreign Affairsin Paris, dated 23 February 1907, coveringthe report fromColonel Bernard, President of the French section of the Commission. The Minister,in his despatch,said: "Themaps indicatingthe frontiercan be broughtup to date in a fairlyshorttime and the plenarymeetingof the French and Siamese Commissionerswill probablybe held before15 March." No meetingapparentlyever took place.In the meantimethe two Govern- ments had entered into negotiationsfor a furtherboundary treaty.This treatywas signed on 23 March 1907, and provided for exchanges of terri- toryand a comprehensiveregulationof all thosefrontiersnot coveredby the previoustreatysettlementof 1904. A second Mixed Commissionof Delimitationwas then set up under the Treaty of 1907.As already mentioned,part of its task was to delimitthat sectorof the Dangrek regionnot having come withinthe ambit of the First Commission,namelyfromthe Pass of Kel westwards,and thereforenot in- cluding Preah Vihear which lay to the east.There was in fact some over- lapping of the workof the two Commissionsin the Kel region,but this over- lapping did not extendto Preah Vihear.There is, however,evidencein the recordsof the Second Commissionthat,at or near the Pass of Kel, the line drawn by this Commissionjoined up with an already existingline proceed- ing eastwardsto the Temple area and beyond.There is no definiteindica- tion as to what this line was, or how it had come to be established; but the presumptionthat it was in some manneror otherthe outcomeof the survey workwhichthe First Commissionhad put in hand, and whichthe President of its French section,in his reportof 20 February 1907, stated to have been accomplishedwithout difficultyis, 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 Commissionwas to delimitthe "new frontiers" establishedby that Treaty, the Commissionalso had the task, under Clause IIIof the Protocol attached to the Treaty, of delimitingall that part of the frontierdefinedin Clause Iof the Protocol.This latter provisionrelated to the entire Dangrek range froma point in its western half to the eastern continuationof the Dangrek, the Pnom Padang range, as far as the River Mekong. Therefore,had the easternDangrek and Pnom Padang sectorsnot already been delimitedby the first(1904)Mixed Com- mission,it would have been the duty of the second (1907)Commissionto do this work.This Commissiondid not do it, apart fromthe overlap (not 1038THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 extending to Preah Vihear)already mentioned,andthereforethe pre- sumptionmustbe that it had already been done. The First Mixed Commissionapparently did not hold any formalmeet- ing after 19 January 1907.It must not be forgottenthat, at the time when such a meetingmighthave been held for the purpose of winding up the workof the Commission,attentionin both countries,on the part of those who were specially qualifiedto act and speak on their behalf in these mat- ters,was directedtowards the conclusionof the Treaty of 23 March 1907. Their chief concern,particularly in the case of Colonel Bernard, could hardly have been the formal completionof the results of the delimitation theyhad carried out. The finalstage of the operationof delimitationwas the preparationand publicationof maps.For the executionof this technicalwork,the Siamese Government,which at that time did not dispose of adequate means, had officiallyrequested that French topographical officersshould mapthe -frontierregion.It is clear fromthe opening paragraph of the minutesof the meetingof the First Mixed Commissionon 29 November1905 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 Ministerin Paris communicatedto his Governmentthe eventual resultsof this work of mapping,he referredto "the Mixed Commissionof Delimitationof the frontiersand the Siamese Commissioners'request that the French Commissionersprepare maps of various frontiers". That this was the deliberatepolicy of the Siamese authoritiesis also shown by the fact that in the Second (1907)Mixed Commission,the French membersof the Commissionwere equally requestedby theirSiamese colleaguesto carry out cartographicalwork,as can be seen fromthe minutesof the meetingof 6 June 1908. The French Governmentduly arrangedforthe workto be done by a team of four French officers,threeof whom,Captains Tixier,Kerler and de Batz, had been membersof the First Mixed Commission.This team workedunder the general directionof Colonel Bernard, and in the late autumn of 1907 it completeda series of eleven maps coveringa large part of the frontiersbe- tween Siam and French Indo-China,including those portionsthat are ma- terial in the present case.The maps were printed and published by a well-knownFrench cartographicalfirm,H.Barrere. The eleven maps were in due course communicatedto the Siamese Gov- ernment,as being the maps requestedby the latter,and the Court will con- sider later the circumstancesof that communicationand the deductionsto be drawn fromit.Three of the maps had been overtakenby events,inas- much as the formerfrontierareas theyshowedhad, by virtue of the Treaty of March 1907, now become situated wholly in Cambodia.Siam was not thereforecalled upon eitherto accept or reject them.Her interestin the othermaps romained. Amongstthese was one of that part of the Dangrek range in whichthe Temple is situated,and on it was traced a frontierline purportingto be the outcomeof the work of delimitationand showingthe whole Preah Vihear promontory,with the Temple area, as being on the 1962]JUDICIALDECISIONS1039 Cambodian side.If thereforethe delimitationcarried out in respectof the easternDangrek sectorestablishedor was intendedto establisha watershed line, this map purportedto show such a line.This map was filedby Cam- bodia as Annex I to its Memorial,and has becomeknown in the case (and will be referredto herein) as the Annex I map. It is on thismap that Cambodia principallyrelies in supportof her claim to sovereigntyover the Temple.Thailand, on the otherhand, contestsany claim based on this map, on the followinggrounds: first,that the map was not the workof the Mixed Commission,and had thereforeno binding char- acter; secondly,that at Preah Vihear the map embodieda material error, not explicableon the basis of any exerciseof discretionarypowersof adapta- tion which the Commissionmay have possessed.This error,according to Thailand's contention,was that the frontierline indicated on the map was not the true watershedline in this vicinity,and that a line drawn in ac- cordance with the true watershedline would have placed, and would now place, the Temple area in Thailand.It is furthercontendedby Thailand that she never accepted this map or the frontierline indicated on it, at any rate so far as Preah Vihear is concerned,in such a way as to becomebound thereby; or, alternativelythat, if she did accept the map, she did so only under, and because of, a mistakenbelief (upon which she relied) that the map line was correctlydrawn to correspondwith the watershedline. The Court will, for the moment,confineitself to the firstof these con- tentions,based on an argumentwhich the Court considers to be correct, namelythat the map was never formallyapproved by the First Mixed Com- missionas such, since that Commissionhad ceased to functionsome months beforethe productionof the map.The record does not show whetherthe map and the line were based on any decisions or instructionsgiven by the Commissionto the surveyingofficerswhile it was still functioning. What is certainis that the map must have had a basis of some sort,and the Court thinkstherecan be no reasonabledoubt that it was based on the work of the surveyingofficersin the Dangrek sector. Being one of the series of maps of the frontierareas produced by French Governmenttopographicalexperts in responseto a request made by the Siamese authorities,printed and pub- lished by a Paris firmof repute,all of whichwas clear fromthe map itself, it was thus investedwith an officialstanding; it had its own inherenttech- nical authority;and its provenancewas open and obvious. The Court must neverthelessconclude that, inits inception, andatthe moment of its production,it had no binding character. Thailand has argued that in the absence of any delimitationapproved and adopted by the Mixed Commission,or based on its instructions,the line of the frontiermust necessarily-by virtue of Article 1 of the Treaty of 1904 followstrictlythe line of the true watershed,and that this line, at Preah Vihear, would place the Temple in Thailand.While admittingthat the Mixed Commissionhad a certain discretionto depart fromthe watershed line in orderto avoid anomalies,and to take account of certainpurely local considerations,Thailandcontends that any departure such asto place Preah Vihear in Cambodia would have far exceeded the scope of any dis- 1040THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 cretionary powers the Mixed Commissioncould have hadauthority to exercisewithoutspecificreferenceto the Governments. Whatever substance these contentionsmay have, taken by themselves, the Court considers that they do not meet the real issues here involved. Even if there was no delimitationof the frontierin the eastern sector of the Dangrek approved and adopted by the Mixed Commission,it was ob- viouslyopen to the Governmentsthemselvesto adopt a delimitationfor that region,makinguse of the workof the technicalmembersof the Mixed Com- mission. As regards any departures from the watershedline which any such delimitationembodied-since, accordingto Thailand's own contention, the delimitationindicated on the Annex I map was not the Mixed Commis- sion's-there is no point in discussingwhethersuch departuresas may have occurredat Preah Vihear fell withinthe Commission'sdiscretionarypowers or not.The point is that it was certainlywithinthe power of the Govern- mentsto adopt such departures. The real question, therefore,which is the essential one in this case, is whetherthe Parties did adopt the Annex I map, and the line indicated on it, as representingthe outcomeof the work of delimitationof the frontier in the regionof Preah Vihear, therebyconferringon it a bindingcharacter. Thailand denies this so far as she is concerned,representingherselfas having adopted a merelypassive attitude in what ensued.She maintains also that a course of conduct,involvingat most a failure to object, cannot sufficeto render her aconsentingparty to adeparture at Preah Vihear from the watershedline specifiedby Article 1 of the Treaty of 1904, so great as to affectthe sovereigntyover the Temple area. The Court sees the matterdifferently.It is clear from the record that the publicationand communicationof the eleven maps referredto earlier, including the Annex Imap, was somethingof an occasion.This was no mere interchangebetween the French and Siamese Governments,though, even if it had been,it could have sufficedin law.On the contrary,the maps were given wide publicity in all technicallyinterestedquarters by being also communicatedto the leading geographicalsocietiesin importantcoun- tries, and to other circles regionally interested; to the Siamese legations accreditedto the British,German,Russian and United States Governments; and to all the membersof the Mixed Commission,French and Siamese.The full original distributionconsistedof about one hundred and sixty sets of eleven maps each.Fifty sets of this distributionwere allocated to the Siamese Government. That the Annex Imap was communicatedas pur- portingto representthe outcomeof the work of delimitationis clear from the letter fromthe Siamese Minister in Paris to the Minister of Foreign Affairsin Bangkok,dated 20 August 1908, in which he said that "regard- ing the Mixed Commissionof Delimitationof the frontiersand the Siamese Commissioners'request that the French Commissionersprepare maps of various frontiers,the French Commissionershave now finishedtheirwork". He added that a series of maps had been broughtto him in order that he mightforwardthemto the Siamese Ministerof Foreign Affairs. He went on to give a list of the eleven maps, including the map of the Dangrek re- 1962]JUDICIALDECISIONS1041 gion-fifty sheets of each.Heended by saying that he was keeping two sheets of each map for his Legation and was sending one sheet of each to the Legations inLondon, Berlin, Russiaandthe United States of America. It has been contendedon behalf of Thailand that this communicationof the maps by the French authoritieswas, so to speak, ex parte, and that no formalacknowledgmentof it was eitherrequestedof, or given by, Thailand. In fact, as will be seen presently,an acknowledgmentby conduct was un- doubtedlymade in a very definiteway; but even if it were otherwise,it is clear that the circumstanceswere such as called for some reaction,withina reasonableperiod, 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 therebymust be held to have acquiesced.Qui tacet consentirevidetur si loqui debuqisset ac potuisset. So far as the Annex I map is concerned,it was not merelythe circum- stancesof the communicationof this and the othermaps that called for some reactionfromthe Siamese side, if reactiontherewas to be; therewere also indicationson the face of the map sheet which required a reaction if the Siamese authoritieshad any reason to contendthat the map did not repre- sent the outcomeof the work of delimitation. The map-together with the othermaps-was,as already stated, communicatedto the Siamese members of the MixedCommission. Thesemust necessarily haveknown (and throughthem the Siamese Governmentmust have known) that this map could not have representedanythingformallyadopted by the Mixed Com- mission,and thereforethey could not possibly have been deceived by the title of the map, namely,"Dangrek-Commission of Delimitationbetween Indo-China and Siam"into supposing that it was purportingto be a pro- duction of the Mixed Commissionas such.Alternatively,if the Siamese membersof the Commissiondid suppose otherwise,this could only have been because, thoughwithoutrecordingthem,the Mixed Commissionhad in fact taken some decisionson whichthe map was based; and of any such decisions the Siamese membersof the Commissionwould of course have been aware. The Siamese membersof the Commissionmust also have seen the notice appearing in the top left-handcorner of the map sheet to the effectthat the workon the groundhad been carried out by Captains Kerler and Oum. They would have known,since theywere presentat the meetingof the Com- mission held on 2 December 1906, that Captain Oum had then been in- structedto carryout the surveyof the easternsectorof the Dangrek range, coveringPreah Vihear, and that he was to leave the next day to take up this assignment. They said nothing-either then or later-tosuggest that the map did not representthe outcomeof the workof delimitationor that it was in any way inaccurate. That the Siamese authoritiesby their conductacknowledgedthe receipt, and recognizedthe character,of these maps, and what they purportedto represent,is shown by the action of the Minister of the Interior, Prince 1042THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 Damrong,in thankingthe French Ministerin Bangkok for the maps, and in asking him for anotherfifteencopies of each of themfor transmissionto the Siamese provincialGovernors. Further evidenceis affordedby the proceedingsof the subsequent Com- missionof Transcriptionwhich met in Bangkok in March of the following year, 1909, and for some monthsthereafter. This was amixed Franco- Siamese Commissionset up by the Parties with the object of getting an officialSiamese geographicalservice started,througha consolidationof all the work of the two Mixed Commissionsof 1904 and 1907.A primaryaim was to convertthe existingmaps into handy atlas form,and to give the French and Siamese terms used in them their proper equivalents in the other languages.No suggestionthat the Annex Imap or line was un- acceptablewas made in the courseof the workof this Commission. It was claimed on behalf of Thailand that the maps received fromParis were onlyseen by minorofficialswho had no experiencein cartography,and would know nothing about the Temple of Preah Vihear.Indeed it was suggestedduringthe oral proceedingsthat no one in Siam at that timeknew anythingabout the Temple or would be troublingabout it. The Court cannot accept these contentionseitheron the facts or the law. If the Siamese authoritiesdid show these maps only to minorofficials,they clearly acted at theirown risk,and the claim of Thailand could not, on the internationalplane, derive any assistance fromthat fact.But the history of the matter,as set out above, shows clearly that the maps were seen by such personsas Prince Devawongse,the Foreign Minister,Prince Damrong, the Ministerof the Interior,the Siamese membersof the First Mixed Com- mission,the Siamese membersof the Commissionof Transcription; and it must also be assumed that the Annex Imap was seen by the Governorof Khukhan province,the Siamese provinceadjoining the Preah Vihear region on the northernside, who must have been amongstthose for whom extra copies were requested by Prince Damrong.None of these persons was a minor official. Allor most had local knowledge.Some must have had knowledgeof the Dangrek region.It is clear fromthe documentationin the case that Prince Damrong took a keen personal interestin the work of delimitation,and had a profoundknowledgeof archaeologicalmonuments. Itis not conceivable that the Governor of Khukhan province, of which Preah Vihear formedpart up to the 1904 settlement,was ignorant of its existence. Inany case this particular contentionof Thailand's is decisively dis- proved by a documentdeposited by Thailand herself,according to which the Temple was in 1899 "re-discovered" by the Siamese Prince Sanphasit, accompaniedby some fifteento twentyofficialsand local dignitaries,includ- ing, it seems, the then Governorand Deputy-Governorof Khukhan.It thus appears that only nine years previous to the receipt of the Annex I map by the Siamese authorities,aconsiderablenumber of persons having high officialstanding in Siam knew of Preah Vihear. The Court moreoverconsidersthat there is no legal foundationfor the consequenceit is attemptedto deduce fromthe fact that no one in Thailand at that timemay have knownof the importanceof the Temple or have been 1962]JUDICIALDECISIONS 1043 troublingabout it.Frontier rectificationscannot in law be claimed on the groundthat a frontierarea has turnedout to have an importancenot known or suspectedwhenthe frontierwas established. It followsfromthe precedingfindingsthat the Siamese authoritiesin due coursereceivedthe Annex I map and that theyaccepted it.Now, however, it is contendedon behalf of Thailand, so far as the disputed area of Preah Vihear is concerned,that an error was committed,an error of whlichthe Siamese authoritieswere unaware at the time when they accepted the map. It is an establishedrule of law that the plea of errorcannot be allowed as an elementvitiating consentif the party advancing it contributedby its own conductto 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 considersthat the characterand qualificationsof the persons who saw the Annex Imap on the Siamese side would alone make it difficultfor Thai- land to plead error in law.These persons included the membersof the very Commissionof Delimitationwithinwhose competencethis sectorof the frontierhad lain.But even apart fromthis, the Court thinksthat there were othercircumstancesrelatingto the Annex I map whichmake the plea of errordifficultto receive. An inspectionindicatesthat the map itselfdrew such pointedattentionto the Preah Vihear regionthat no interestedperson,nor anyone chargedwith the duty of scrutinizingit, could have failed to see what the map was pur- porting to do in respect of that region.If, as Thailand has argued, the geographicalconfigurationof the place is such as to make it obvious to any- one who has been there that the watershedmust lie along the line of the escarpment(a fact which,if true,must have been no less evidentin 1908), then the map made it quite plain that the Annex I line did not follow the escarpmentin this region since it was plainly drawn appreciably to the northof the whole Preah Vihear promontory. Nobody looking at the map could be under any misapprehensionabout that. Next, the map marked Preah Vihear itself quite clearly as lying on the Cambodian side of the line, using for the Temple a symbolwhich seems to indicate a rough plan of the building and its stairways. It would thus seem that, to anyone who consideredthat the line of the watershedat Preah Vihear ought to follow the line of the escarpment,or whose duty it was to scrutinizethe map, therewas everythingin the Annex I map to put him upon enquiry. Furthermore,as has already been pointed out, the Siamese Governmentknew or must be presumed to have known, throughthe Siamese membersof the Mixed Commission,that the Annex I map had never been formallyadopted by the Commission. The Siamese authoritiesknew it was the work of French topographicalofficersto whom they had themselvesentrustedthe work of producingthe maps.They ac- cepted it withoutany independentinvestigation,and cannot thereforenow plead any errorvitiatingthe realityof their consent. The Court concludes thereforethat the plea of errorhas not been made out. The Court will now considerthe events subsequent to the period 1904- 1909. The Siamese authoritiesdid not raise any query about the Annex I map 1044THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 as betweenthemselvesand France or Cambodia, or expresslyrepudiate it as such, until the 1958 negotiationsin Bangkok,when,inter altia,the ques- tion of Preah Vihear came under discussion between Thailand and Cam- bodia.Nor was any question raised even after 1934-1935, when Thailand carried out a surveyof her own in this region,and this surveyhad, in Thai- land'sview, establishedadivergencebetween the map line and the true line of the watershed-a divergencehaving the effectof placing the Temple inCambodia.Although, after this date, Thailand eventually produced some maps of her own showing Preah Vihear as being in Thailand, she continued,even for public and officialpurposes, to use the Annex Imap, or othermaps showingPreah Vihear as lying in Cambodia,withoutraising any query about the matter (her explanationsas to this will be considered presently).Moreover,the Court finds it difficultto overlooksuch afact as, for instance,that in 1937, even after Thailand's own survey in 1934- 1935, and in the same year as the conclusion of atreaty with France in which, as will be seen, the established commonfrontierswere reaffirmed, the Siamese Royal Survey Department produced amap showing Preah Vihear as lying in Cambodia. Thailand had several opportunitiesof raisingwith the French authorities the question of the Annex Imap.There were firstof all the negotiations for the 1925 and 1937 Treaties of Friendship, Commerceand Navigation between France, on behalf of Indo-China, and Siam.These Treaties, al- thoughthey provided for a general process of revision or replacementof previous Agreements,excluded fromthis process the existing frontiersas they had been establishedunder the Boundary Settlementsof 1893, 1904 and 1907.Thereby,and in certain more positive provisions,the Parties confirmedthe existingfrontiers,whatevertheywere.These were occasions (particularly in regard to the negotiationsfor the 1937 Treaty,which oc- curred only two years after Thailand's own survey of the frontierregions had disclosed,in her belief,a serious divergencebetweenthe map line and the watershedline at Preah Vihear) on which it would have been natural for Thailand to raise the matter,if she consideredthe map indicatingthe frontierat Preah Vihear to be incorrect-occasionson 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 showingPreah Vihear as being in Cambodia.That this map may have been intendedfor internal militaryuse does not seem to the Court to make it any less evidence of Thailand's state of mind.The inferencemust 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, afterher own surveyof 1934-1935,she thoughtshe knew it was incorrect. Thailand having temporarilycome into possession of certain parts of Cambodia, including Preah Vihear, in 1941, the Ministryof Information of Thailand published a work entitled "Thailandduring national recon- struction" in which it was stated in relation to Preah Vihear that it had now been "retaken" for Thailand.This has been representedby Thailand as being an erroron the part of a minorofficial. Nevertheless,similar lan- 1962]JUDICIALDECISIONS1045 guage, suggestingthat Thailand had been in possession of Preah Vihear only since about 1940, was used by representativesof Thailand in the terri- torial negotiations that took placebetween Thailand andCambodia at Bangkok in 1958. Afterthe war, by a SettlementAgreementof November1946 withFrance, Thailand accepted a reversionto the status quo ante 1941.It is Thailand's contentionthat this reversionto the status quo did not affectPreah Vihear because Thailand already had sovereigntyover it before the war.The Court need not discuss this contention,for whetherThailand did have such sovereigntyis preciselywhat is in issue in these proceedings. The impor- tant point is that,in consequenceof the war events,France agreed to set up a Franco-SiameseConciliationCommissionconsistingof the two representa- tives of the Parties and threeneutral Commissioners,whose termsof refer- ence were specificallyto go into,and make recommendationson an equitable basis in regard to, any complaintsor proposals for revisionwhich Thailand mightwish to make as to, inter altia,the frontiersettlementsof 1904 and 1907.The Commissionmet in 1947 in Washington,and here thereforewas anoutstandingopportunityfor Thailand to claim arectificationof the frontierat Preah Vihear on the ground that the delimitationembodied a serious errorwhichwould have caused Thailand to reject it had she known of the error in 1908-1909.Infact, although Thailand made complaints about the frontierline in a considerablenumberof regions,she made none about Preah Vihear.She even (12 May 1947) filedwith the Commissiona map showingPreah Vihear as lying in Cambodia.Thailand contendsthat this involved no adverse implicationsas regards her claim to the Temple, because the Temple area was not in issue beforethe Commission,that it was otherregionsthat were under discussion,and that it was in relationto 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, everythingelse apart, Thailand was by this time well aware, fromcertainlocal happeningsin relationto the Temple, to be men- tionedpresently,that France regardedPreah Vihear as being in Cambodian territory-evenif this had not already and long since been obviousfromthe frontierline itself,as mapped by the French authoritiesand communicated to the Siamese Governmentin 1908.The natural inferencefromThailand's failure to mentionPreah Vihear on this occasion is, again, that she did not do so because she accepted the frontierat this point as it was drawn on the map, irrespectiveof its correspondencewiththe watershedline. As regardsthe use of a map showingPreah Vihear as lying in Cambodia, Thailand maintains that this was for purely cartographicalreasons, that therewere no othermaps, or none that were so convenient,or none of the rightscale for the occasion.The Court does not findthis explanation con- vincing.Thailand could have used the map but could also have entered some kind of reservationwith France as to its correctness. This she did not do. As regardsher failure even to raise the questionof the map as such until 1958, Thailand states that this was because she was, at all material times, 1046THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 in possessionof Preah Vihear; thereforeshe had no need to raise the mat- ter.She indeed instancesher acts on the ground as evidencethat she never accepted the Annex I line at Preah Vihear at all, and contendsthat if she never accepted it she clearly had no need to repudiate it, and that no ad- verse conclusionscan be drawn fromher failureto do so.The acceptability of this explanationmust obviouslydepend on whetherin fact it is the case that Thailand's conduct on the ground affordsex post facto evidence suffi- cient to show that she never accepted the Annex Iline in 1908 in respect of Preah Vihear, and consideredherselfat all material times to have the sovereigntyover the Temple area. The Court has consideredthe evidence furnishedby Thailand of acts of anadministrativecharacter performedby her officialsat or relative to Preah Vihear.France, and subsequentlyCambodia, in view of her title founded on the Treaty of 1904, performedonly a very few routineacts of administrationin this small, desertedarea.It was specificallyadmittedby Thailand in the course of the oral hearingthat if Cambodia acquired sover- eigntyoverthe Temple area by virtueof the frontiersettlementof 1904, she did not subsequentlyabandon it, nor did Thailand subsequentlyobtain it by any process of acquisitive prescription. Thailand's acts on the ground were thereforeput forwardas evidence of conduct as sovereign,sufficient to negativeany suggestionthat,under the 1904 Treaty settlement,Thailand accepted a delimitationhaving the effectof attributingthe sovereigntyover Preah Vihear to Cambodia.It is thereforefromthis standpointthat the Court must considerand evaluate these acts.The real question is whether theysufficedto effaceor cancel out the clear impressionof acceptance of the frontierline at Preah Vihear to be derived fromthe various considerations already discussed. With one or two importantexceptionsto be mentionedpresently,the acts concernedwere exclusivelythe acts of local, provincial,authorities. To the extentthat theseactivitiestook place, it is not clear that theyhad reference to the summitof Mount Preah Vihear and the Temple area itself,rather than to places somewherein the vicinity. But howeverthat may be, the Court findsit difficultto regard such local acts as overridingand negativing the consistentand undeviatingattitude of the central Siamese authorities to the frontierline as mapped. Inthis connection,much the most significantepisode consisted of the visit paid to the Temple in 1930 by Prince Damrong, formerlyMinisterof the Interior, and at this time President of the Royal Institute of Siam, charged with duties in connectionwith the National Library andwith archaeological monuments. The visit was part of an archaeological tour made by the Prince with the permissionof the King of Siam, and it clearly had a quasi-officialcharacter. When the Prince arrived at Preah Vihear, he was officiallyreceived 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 implica- tions of a receptionof this character. A clearer affirmationof title on the French Indo-Chineseside can scarcely be imagined.It demanded a reac- 1962]JUDICIALDECISIONS1047 tion.Thailand did nothing. Furthermore,when Prince Damrong on his return to Bangkok sent the French Resident some photographsof the oc- casion, he used language which seems to admit that France, throughher Resident,had acted as the host country. The explanations regarding Prince Damrong's visit given on behalf of Thailand have not been found convincingby the Court.Looking at the incidentas a whole,it appears to have amountedto a tacit recognitionby Siam of the sovereigntyof Cambodia (under French Protectorate) over Preah Vihear, througha failure to react in any way, on an occasion that called for a reaction in order to affirmor 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-andthis would be whollyconsistentwith her at- titude all along, and thereafter,to the Annex Imap and line-orelse she decided not to assert it, which again means that she accepted the French claim,or accepted the frontierat Preah Vihear as it was drawn on the map. The remainingrelevant facts must now be stated.InFebruary 1949, not long after the conclusion of the proceedings of the Franco-Siamese ConciliationCommission,in the course of which,as has been seen, Thailand did not raise the question of Preah Vihear, France addressed a Note to the Governmentof Thailand stating that areport had been received of the stationingof four Siamese keepers at the Temple, and asking for informa- tion.There was no reply to this note, nor to a follow-upNote of March 1949.In May 1949, France sent a furtherNote, setting out briefly,but quite explicitly,the groundson whichshe consideredPreah Vihear to be in Cambodia, and pointingout that a map produced by Thailand herselfhad recognizedthis fact.The withdrawal of the keepers was requested.Al- thoughthere was an error in this Note, the significanceof the latter was that it contained an unequivocal assertion of sovereignty. This French Note also receivedno reply.In July 1950, a furtherNote was sent.This too remainedunanswered. In these circumstancesCambodia,on attainingher independencein 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 keeperswere already there,the Cambodiankeeperswithdrew,and Cambodia sent a Note dated January 1954 to the Governmentof Thailand asking for information. This received a mere acknowledgment,but no explanation. Nor was there,even then,any formalaffirmationof Thailand's claim.At the end of March 1954, the Governmentof Cambodia, drawing attentionto the fact that no substantivereply to its previous Note had been received, notifiedthe Governmentof Thailand that it now proposed to replace the previouslywithdrawnCambodian keepers or guards by some Cambodian troops.In this Note Cambodia specificallyreferredto the justificationof the Cambodian claim contained in the French Note of May 1949.This Cambodian Note also was not answered.However, the Cambodian troops were not in fact sent; and in June 1954, Cambodia addressed to Thailand a furtherNote statingthat,as informationhad been receivedto the effectthat Thai troops were already in occupation, the despatch of the Cambodian 1048THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 troops had been suspended in order not to aggravate the situation.The Note went on to ask that Thailand should either withdrawher troops or furnishCambodia withher views on the matter. This Note equally received no reply.But the Thai "troops"(the Court understandsthat they are in fact a police force) remained. Again, therefore,it would seem that Thai- land, while taking certain localaction, wasnot prepared to deny the French and Cambodian claim at the diplomaticlevel. No furtherdiplomatic correspondencewas produced to the Court; but eventually,in 1958, aconferencewas held at Bangkok between Thailand and Cambodia,to discuss various territorialmattersin dispute betweenthe Parties, including that of Preah Vihear.The representativeof Thailand having declined to discuss the legal aspects of the matter,the negotiations broke down and Cambodia institutedthe presentproceedings. The Courtwill now state the conclusionsit draws fromthe facts as above set out. Even if therewere any doubt as to Siam's acceptance of the map in 1908, and henceof the frontierindicatedthereon,the Court would consider,in the light of the subsequentcourse of events,that Thailand is now precluded by her conduct fromassertingthat she did not accept it.She has, for fifty years, enjoyed such benefitsas the Treaty of 1904 conferredon her, if only the benefitof a stable frontier. France, and throughher Cambodia, relied on Thailand's acceptance of the map.Since neitherside can plead error, it is immaterialwhetheror not this reliance was based on a belief that the map was correct. It is not now open to Thailand, while continuingto claim andenjoy the benefitsof the settlement,to deny that she wasever a consentingparty to it. The Court howeverconsidersthat Thailand in 1908-1909 did accept the Annex I map as representingthe outcomeof the work of delimitation,and hence recognizedthe line on that map as being the frontierline, the effect of which is to situate Preah Vihear in Cambodian territory. The Court considersfurtherthat,looked at as a whole,Thailand's subsequentconduct confirmsand bears out her original acceptance, and that Thailand's acts on the ground do not sufficeto negative this.Both Parties, by their con- duct, recognizedthe line and therebyin effectagreed to regard it as being the frontierline. The Court must now consider two furthermatters. Thailand contends that since 1908, and at any rate up to her own 1934-1935 survey,she be- lieved that the map line and watershedline coincided,and thereforethat if she accepted the map line, she did so only in that belief.It is evident that such a contentionwould be quite inconsistentwith Thailand's equally stronglyadvanced contentionthat these acts in the concreteexerciseof sov- ereigntyevidenced her belief that she had sovereigntyover the Temple area: for if Thailand was trulyunder a misapprehensionabout the Annex I line-ifshe really believedit indicatedthe correctwatershedline-thenshe must have believed that, on the basis of the map and her acceptance of it, the Temple area lay rightfullyin Cambodia.If she had such a belief-and such a belief is implicit in any plea that she had accepted the Annex I 1962]JUDICIALDECISIONS1049 map only because she thoughtit was correct-then her acts on the ground would have to be regarded as deliberateviolationsof the sovereigntywhich (on the basis of the assumptionsabove stated) she must be presumed to have thoughtCambodia to possess.The conclusionis that Thailand cannot allege that she was under any misapprehensionin accepting the Annex I line, for this is whollyinconsistentwith the reason she gives for her acts on the ground,namely that she believed herselfto possess sovereigntyin this area. It may be added that even if Thailand's plea of misapprehensioncould, in principle,be accepted, it should have been advanced shortlyafter Thai- land'sown survey of the disputed region was carried out in 1934-1935. Since then Thailand could not have been under any misapprehension. There is finallyone furtheraspect of the case with which the Court feels it necessaryto deal.The Court considersthat the acceptance of the Annex I map by the Parties caused the map to enterthe treatysettlementand to becomean integralpart of it.It cannot be said that this process involved a departurefrom,and even a violation of, the termsof the Treaty of 1904, whereverthe map line divergedfromthe line of the watershed,for, as the Court sees the matter,the map (whetherin all respectsaccurate by refer- ence to the true watershedline or not) was accepted by the Parties in 1908 and thereafteras constitutingthe result of the interpretationgiven by the two Governmentsto the delimitationwhich the Treaty itselfrequired.In otherwords,the Parties at that time adopted an interpretationof the treaty settlementwhich caused the map line, in so far as it may have departed fromthe 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 matternow as one solely of ordinarytreatyinterpretation,it considersthat the interpretationto be given would be the same,for the followingreasons. In general,when two countriesestablisha frontierbetweenthem,one of the primaryobjects is to achieve stabilityand finality. This is impossible if the line so establishedcan, at any moment,and on the basis of acon- tinuously available process, becalledinquestion, andits rectification claimed, wheneverany inaccuracy by referenceto aclause in the parent treatyis discovered. Such a processcould continueindefinitely,and finality would never be reached so long as possible errorsstill remainedto be dis- covered.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 frontierline in this region would be the watershed. There are boundary treatieswhich do no more than referto a watershed line, or to a crestline, and whichmake no provision for any delimitationin addition.The Parties in the present case must have had a reason for taking this furtherstep. This could only have been because they regarded a watershedindicationas insufficientby itself to achieve certaintyand finality. Itis precisely to achieve this that delimitationsand map lines are resortedto. Various factorssupport the view that the primaryobject of the Parties in the frontiersettlementsof 1904-1908 was to achieve certaintyand fi- 1050THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 nality.From the evidence furnishedto the Court, and from the state- mentsof the Parties themselves,it is clear that the whole questionof Siam's very long frontierswith French Indo-China had, in the period prior to 1904, been a cause of uncertainty,trouble and friction,engenderingwhat was describedin one contemporarydocumentplaced beforethe Court as a state of "growing tension" in the relations between SiamandFrance. The Court thinksit legitimateto conclude that an important,not to say a paramount object of the settlementsof the 1904-1908 period(which broughtabout a comprehensiveregulationof all outstandingfrontierques- tions betweenthe two countries),was to put an end to this state of tension and to achieve frontierstabilityon a basis of certaintyand finality. In the Franco-Siamese Boundary Treaty of 23 March 1907, the Parties recitedin the preamblethat theywere desirous"of ensuringthe finalregu- lation of all questionsrelatingto the commonfrontiersof Indo-China and Siam".A furthertokenof the same object is to be found in the desire,of which the documentationcontains 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 certaintyand finalityby means of natural and visible lines. The same view is stronglysupportedby the Parties' attitude over fron- tiers in the 1925 and 1937 Treaties.By specificallyexcluding frontiers fromthe process of revisionof previous treaties,which the 1925 and 1937 Treaties otherwiseeffected,the Parties bore witness to the paramount im- portancethey attached to finalityin this field. Their attitude in 1925 and 1937 can properlybe taken as evidencethat they equally desired finalityin the 1904-1908period. The indication of the line of the watershed in Article 1of the 1904 Treatywas itselfno morethan an obviousand convenientway of describing a frontierline objectively,thoughin general terms. There is, however,no reason to thinkthat the Parties attached any special importanceto the line of the watershedas such, as compared with the overridingimportance,in the interestsof finality,of adheringto the map line as eventuallydelimited and as accepted by them. The Court,therefore,feels bound,as a matterof treatyinterpretation,to pronouncein favour of the line as mapped in the disputed area. Given the grounds on which the Court bases its decision,it becomesun- necessaryto considerwhether,at Preah Vihear, the line as mapped does in fact correspondto the true watershedline in this vicinity,or did so cor- respond in 1904-1908,or, if not, how the watershedline in fact runs. Referringfinallyto the Submissions presented at the end of the oral proceedings,the Court, for the reasons indicated at the beginningof the presentJudgment,findsthat Cambodia's firstand second Submissions,call- ing for pronouncementson the legal status of the Annex I map and on the frontierline in the disputed region,can be entertainedonly to the extent that they give expressionto grounds,and not as claims to be dealt with in the operativeprovisions of the Judgment. It findson the other hand that 1962]JUDICIAL DECISIONS1051 Thailand, after having stated her own claim concerningsovereigntyover Preah Vihear, confinedherselfin her Submissionsat the end of the oral proceedingsto argumentsand denials opposingthe contentionsof the other Party, leaving it to the Court to word as it sees fitthe reasons on which its Judgmentis based. In the presence of the claims submittedto the Court by Cambodia and Thailand, respectively,concerningthe sovereigntyover Preah Vihear thus in dispute betweenthese two States, the Court findsin favour of Cambodia in accordance with her third Submission. It also findsin favour of Cam- bodia as regards the fourthSubmission concerningthe withdrawalof the detachmentsof armed forces. As regards the fifthSubmissionof Cambodia concerningrestitution,the Court considersthat the request made in it does not representany exten- sion of Cambodia's original claim (in which case it would have been irre- ceivable at the stage at which it was firstadvanced).Rather is it, like the fourth Submission,implicit in, andconsequential on, the claim of sov- ereigntyitself.On the other hand, no concreteevidence has been placed beforethe Court showingin any positiveway that objects of the kind men- tioned in this Submissionhave in fact been removedby Thailand fromthe Temple or Temple area since Thailand's occupationof it in 1954.It is true that Thailand has not so much denied the allegation as contendedthat it is irreceivable. In the circumstances,however,the question of restitutionis one on which the Court can only give a findingof principle in favour of Cambodia,withoutrelatingit to any particular objects. For these reasons, THECOURT, by nine votes to three, findsthat the Temple of Preah Vihear is situated in territoryunder the sovereigntyof Cambodia; finds in consequence, by nine votes to three, that Thailand is under an obligation to withdraw any military or police forces,or otherguards or keepers,stationedby her at the Temple, or in its vicinity on Cambodian territory; by seven votes to five,3 that Thailand is under an obligation to restoreto Cambodia any objects of the kind specifiedin Cambodia's fifthSubmission4which may, since the date of the occupation of the Temple by Thailand in 1954, have been removed fromthe Temple or the Temple area by the Thai authorities. 3 On this point Judges Tanaka and Morelli joined the dissentingJudges (Moreno Quintana,WellingtonKoo, and Sir Percy Spender), on the groundthat the Court shouldnot pass upon the Fifth Submissionby Cambodia,since it was not put forward untilduringthe courseof the hearings. 4 The Fifth Submission,put forwardby Cambodia on March 20, 1962, asked the Court " to adjudge and declare that the sculptures,stelae, fragmentsof monuments, sandstonemodeland ancientpottery whichhave been removedfromthe Templeby the Thai authoritiessince 1954 are to be returnedto the Governmentof the Xingdomof Cambodiaby the Governmentof Thailand." 1052THEAMERICANJOURNALOFINTERNATIONALLAW[Vol. 56 [Concurring in the result, Judges Alfaro and Fitzmaurice gave indi- vidual opinions. Judge Alfaro discussed at lengththe principle of "estop- pel"or "preclusion" "that a State party to an internationallitigationis bound by its previous acts or attitudewhen they are in contradictionwith its claims in the litigation."Pointing out the differenceof this principle fromthe Anglo-Americanlaw of estoppel,he declared that "Itspurpose is always the same: aState must not be permittedto benefitby its own in- consistencyto the prejudice of another State,"and said:"Failureof a State to assert its right when that right is openly challenged by another State can only mean abandonmentto [of] that right."Judge Fitzmaurice wished to discuss certainpoints of the case more fully. Inhis dissentingopinion Judge Moreno Quintana held the treaty text more importantthan maps, that the interpretationof the treaty called for a watershedboundary,and that the watershedfollowedthe edge of the cliff of the promontoryon whichthe Temple is situated,thus placing the Temple in Thailand.Judge Wellington Koo'sdissentingopinion concluded that the "Annex map"did not have the characterof an internationalagree- ment; that Thailand's conduct did not show acquiescence in any line plac- ing the Temple in Cambodia; that there was no ground to hold Thailand accountablefor acquiescenceor for the application of the idea of preclusion or estoppel; urged that independentexperts should have found the actual watershed,and concludedthat he could not reach a satisfactoryconclusion as to the exact boundary withoutknowingthe answers to technical ques- tions concerningthe watershed lineinthe disputed area.SirPercy Spender gave a lengthydissentingopinion in whichhe found no agreement to deviate fromthe treatyline of the watershed,and that the Annex I map did not in the vicinity of the Temple indicate the real agreementof the parties, although neither Francenor Thailand wasawareof this dis- crepancy until long after the map was published.Hedid not find any basis for holdingthat acquiescence had precluded Thailand fromasserting the true treaty-boundaryline.He stated: There is however,in my view, no foundationin internationallaw for the propositionthat an act of recognitionby a State of or acquiescence by aState in a situation of fact or law is aunilateral juridical act which, operating of its own force, has the legal consequence of pre- cluding a party giving or making it from thereafterchallengingthe situation which is the subject of recognitionor acquiescence. The principleof preclusionis a beneficientand powerfulinstrument of substantiveinternationallaw.Based as it is upon the necessityfor good faith betweenStates in their relationsone with another,it is not to be hedged in by artificialrules.It should not howeverbe permitted to becomeso indefiniteas to acquire the somewhatformlesscontentof a maxim. And since the principle,when it is applicable to any given set of facts, substitutesrelative truth for the judicial search for the truth,it should be applied with caution. In my opinion the principle operates to preventaState contesting beforethe Court a situationcontraryto a clear and unequivocal repre- sentationpreviouslymade by it to another State, either expresslyor impliedly,on which representationthe otherState was, in the circum- stances,entitledto rely and in fact did rely,and as a result that other State has been prejudiced or the State making it has secured some benefitor advantage for itself. Unless the elementsso stated can, in any particular case, be shown to exist,the principle has no application. 1962]JUDICIALDECISIONS1053 I greatlydoubt whetherany of the elementsof preclusionhave been established by Cambodia.Even were it established that Thailand's conduct did amount to some clear andunequivocal representation, and that France relied upon it and was entitled to do so, Ido not think there is any evidence that France-orCambodia-suffered any prejudice.] Resolution1731 (XVI)of General Assemblyrequestingadvisoryopin- ion-objections to giving opinion based on proceedingsin General Assembly-interpretationof meaning of "expenses of the Organi- zation"-Article17, paragraphs 1 and 2 of Charter-lack of justifi- cation for limitingterms"budget"and "expenses "-Article17 in context of Charter-respective functions of Security Council and GeneralAssembly-Article 11, paragraph 2, in relationto budgetary powers of General Assembly-role of General Assemblyin mainte- nance of internationalpeace and security-agreementsunder Ar- ticle 43-expensesincurredfor purposes of United Nations-obliga- tions incurred bySecretary-Generalacting under authority of Security Council orGeneral Assembly-nature of operations of UNEFand ONUC-financing of UNEFand ONUC based on Article 17, paragraph 2-implententationby Secretary-Generalof Security Council resolutions-expendituresfor UNEFand ONUC and Article 17, paragraph 2, of Charter 1 CERTAINEXPENSESOF THE UNITEDNATIONS(ARTICLE17, PARAGRAPH 2, OF THE CHARTER).2I.C.J. Reports,1962, p. 151. InternationalCourt of Justice,3AdvisoryOpinion of July 20, 1962. [Resolution 1731(XVI),adopted December 20, 1961, by the General Assembly,read: The General Assembly, Recognizing its need for authoritativelegal guidance as to obliga- tions of MemberStates under the Charterof the United Nations in the matterof financingthe United Nations operationsin the Congo and in the Middle East, 1.Decides to submit the following question to the International Court of Justicefor an advisoryopinion: "Dothe expendituresauthorizedin General Assemblyresolutions 1583 (XV)and 1590 (XV)of 20 December 1960, 1595(XV)of 3 April 1961, 1619(XV)of 21 April 1961 and1633(XVI)of 30 October1961 relatingto the United Nations operationsin the Congo undertakenin pursuance of the Security Council resolutionsof 14 July, 22 July and 9 August 1960, and 21 February and 24 Novem- ber 1961, andGeneral Assembly resolutions 1474 (ES-IV)of 20 September1960 and 1599 (XV),1600(XV),and 1601(XV) of 15 1 Captionby the Court. 2Full text of majorityopinion,except for introductorymatter,and digests of re- mainder,by Wm. W. Bishop, Jr. 8 Composedfor this case of PresidentWiniarski,Vice PresidentAlfaro,and Judges Basdevant,Badawi, MorenoQuintana,WellingtonKoo, Spiropoulos,Sir Percy Spender, Sir GeraldFitzmaurice,Koretsky,Tanaka, Bustamantey Rivero,Jessup,and Morelli.