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II. Substantive International Law - Second Part
1.2. Boundaries
1.2.4.Principle of "uti possidetis"

¤ Land, Island and Maritime Frontier Dispute
(El Salvador/Honduras: Nicaragua intervening),
Judgment of 11 September 1992,
I.C.J. Reports 1992, p. 351

[p. 380] 28. The two Parties (and the intervening State) are States which came into existence with the break-up of the Spanish Empire in Central America, and their territories correspond to administrative sub-divisions of that empire. While it was from the outset accepted that the new international boundaries should be determined by the application of the principle generally accepted in Spanish America of the uti possidetis juris, whereby the boundaries were to follow the colonial administrative boundaries, the problem, as in the case of many other boundaries in the region, was to determine where those boundaries actually lay. In the words of the 1933 Award of the Arbitral Tribunal presided over by Chief Justice Charles Evans Hughes in the case concerning the border between Guatemala and Honduras, in which the task of the arbitrator was to determine the "juridical line" of the "uti possidetis of 1821",

"It must be noted that particular difficulties are encountered in drawing the line of 'uti possidetis of 1821', by reason of the lack of trustworthy information during colonial times with respect to a large part of the territory in dispute. Much of this territory was unexplored. Other parts which had occasionally been visited were but vaguely known. In consequence, not only had boundaries of jurisdiction not been fixed with precision by the Crown, but there were great areas in which there had been no effort to assert any semblance of administrative authority." (United Nations, Reports of International Arbitral Awards, Vol. II, p. 1325.)

[pp. 386-388] 40. Both Parties are agreed that the primary principle to be applied for the determination of the land frontier is the uti possidetis juris; even though this, unusually for a case of this kind, is not expressly mentioned in Article 5 of the Special Agreement, nor in the General Treaty of Peace, to which, as explained below, the Chamber is referred by the Special Agreement. For Honduras the norm of international law applicable to the dispute is simply the uti possidetis juris; El Salvador, relying on the terms of Article 26 of the General Treaty of Peace, strongly contests that this is the sole law applicable, and invokes, as well as the uti possidetis juris, what have been variously called "arguments of a human nature" or "effectivités", to be examined further on in this Judgment.

41. There can be no doubt about the importance of the uti possidetis juris principle as one which has, in general, resulted in certain and stable frontiers throughout most of Central and South America, or about the applicability of that principle to the land boundary between the Parties in the present case. Nevertheless these certain and stable frontiers are not the ones that find their way before international tribunals for decision. These latter frontiers are almost invariably the ones in respect of which uti possidetis juris speaks for once with an uncertain voice. It can indeed almost be assumed that boundaries which, like the ones in this case, have remained unsettled since independence, are ones for which the uti possidetis juris arguments are themselves the subject of dispute. It is not a matter of surprise, therefore, that the Chamber has not found these land-frontier questions easy to determine; and it may be useful briefly to indicate some of the considerations that have tended to be common to the sectors submitted to the Chamber.

42. The meaning of the principle of uti possidetis juris is authoritatively stated in the Judgment of the Chamber in the Frontier Dispute case:

"The essence of the principle lies in its primary aim of securing respect for the territorial boundaries at the moment when independence is achieved. Such territorial boundaries might be no more than delimitations between different administrative divisions or colonies all subject to the same sovereign. In that case, the application of the principle of uti possidetis resulted in administrative boundaries being transformed into international frontiers in the full sense of the term." (I.C.J. Reports 1986, p. 566, para. 23.)

And in the Arbitral Award of the Swiss Federal Council of 24 March 1922 concerning certain boundary questions between Colombia and Venezuela, it had been observed that:

"This general principle offered the advantage of establishing an absolute rule that there was not in law in the old Spanish America any terra nullius; while there might exist many regions which had never been occupied by the Spaniards and many unexplored or inhabited by non-civilized natives, these regions were reputed to belong in law to whichever of the Republics succeeded to the Spanish province to which these territories were attached by virtue of the old Royal ordinances of the Spanish mother country. These territories, although not occupied in fact were by common consent deemed to be occupied in law from the first hour by the new Republic ..." (UNRIAA,Vol. I, p. 228.)

Thus the principle of uti possidetis juris is concerned as much with title to territory as with the location of boundaries; certainly a key aspect of the principle is the denial of the possibility of terra nullius.

43. To apply this principle is not so easy when, as in Spanish Central America, there were administrative boundaries of different kinds or degrees; for example, besides "provinces" (a term of which the meaning was different at different periods), there were Alcaldías Mayores and Corregimientos and later on, in the 18th century, Intendencias, as well as the territorial jurisdictions of a higher court (Audiencias), Captaincies-General and Vice-Royalties; and indeed the territories which became El Salvador and Honduras were, before 1821, all part of the same larger administrative area, the Captaincy-General or Kingdom of Guatemala. Furthermore, the jurisdictions of general administrative bodies such as those referred to did not necessarily coincide in territorial scope with those of bodies possessing particular or special jurisdictions, e.g., military commands. Besides, in addition to the various civil territorial jurisdictions, general or special, there were the ecclesiastical jurisdictions, which were supposed to be followed in principle, pursuant to general legislation, by the territorial jurisdiction of the main civil administrative units in Spanish America; such adjustment often needed, however, a certain span of time within which to materialize. Fortunately, in the present case, insofar as the sectors of the land boundary are concerned, the Parties have indicated to which colonial administrative divisions they claim to have succeeded; the problem is to identify the areas, and their boundaries, which corresponded to these divisions, to be referred to herein, for the sake of simplicity, as "provinces" which in 1821 became respectively El Salvador and Honduras, initially as constituent States of the Federal Republic of Central America. Moreover it has to be remembered that no question of international boundaries could ever have occurred to the minds of those servants of the Spanish Crown who established administrative boundaries; uti possidetis juris is essentially a retrospective principle, investing as international boundaries administrative limits intended originally for quite other purposes.

[pp. 388-389] 44. Neither Party has however produced any legislative or similar material indicating specifically, with the authority of the Spanish Crown, the extent of the territories and the location of the boundaries of the relevant provinces in each area of the land boundary. Both Parties have instead laid before the Chamber numerous documents, of different kinds, some of which, referred to collectively as "titles" (títulos), concern grants of land in the areas concerned by the Spanish Crown, from which, it is claimed, the provincial boundaries can be deduced. Some of these actually record that a particular landmark or natural feature marked the boundary of the provinces at the time of the grant; but for the most part this is not so, and the Chamber is asked, in effect, to conclude, in the absence of other evidence of the position of a provincial boundary, that where a boundary can be identified between the lands granted by the authorities of one province and those granted by the authorities of the neighbouring province, this boundary may be taken to have been the provincial boundary and thus the line of the uti possidetis juris. Thus it was the territorial aspect of that principle rather than its boundary aspect that was the one mainly employed by both Parties in their arguments before the Chamber. The location of boundaries seemed often, in the arguments of the Parties, to be incidental to some "claim", or "title", or "grant", respecting a parcel of territory, within circumambient boundaries only portions of which are now claimed to form an international boundary. It is rather as if the disputed boundaries must be constructed like a jig-saw puzzle from certain already cut pieces so that the extent and location of the resulting boundary depend upon the size and shape of the fitting piece.

45. The term "title" has in fact been used at times in these proceedings in such a way as to leave unclear which of the several possible meanings is to be attached to it; some basic distinctions may therefore perhaps be usefully stated. As the Chamber in the Frontier Dispute case observed, the word "title" is generally not limited to documentary evidence alone, but comprehends "both any evidence which may establish the existence of a right, and the actual source of that right" (I.C.J. Reports 1986, p. 564, para. 18). In one sense, the "title" of El Salvador or of Honduras to the areas in dispute, in the sense of the source of their rights at the international level, is, as both Parties recognize, that of succession of the two States to the Spanish Crown in relation to its colonial territories; the extent of territory to which each State succeeded being determined by the uti possidetis juris of 1821. Secondly, insofar as each of the two States inherited the territory of particular administrative units of the colonial structure, a "title" might be furnished by, for example, a Spanish Royal Decree attributing certain areas to one of those. As already noted, neither Party has been able to base its claim to a specific boundary line on any "titles" of this kind applicable to the land frontier. Reserving, for the present, the special status attributed by El Salvador to "formal title-deeds to commons" (paragraphs 51-53 below), the títulos submitted to the Chamber recording the grant of particular lands to individuals or to Indian communities cannot be considered as "titles" in this sense; they could rather be compared to "colonial effectivités" as defined by the Chamber formed to deal with the Frontier Dispute: "the conduct of the administrative authorities as proof of the effective exercise of territorial jurisdiction in the region during the colonial period" (I.C.J. Reports 1986, p. 586, para. 63). These, or some of them, are however "titles" in a third, municipal-law, sense, in that they evidence the right of the grantees to ownership of the land defined in them. In some cases, the grant of the "title" in this third sense was not perfected; but the record, particularly of any survey carried out, nevertheless remains a "colonial effectivity" which may be of value as evidence of the position of the provincial boundary. In respect of one particular class of these títulos, referred to as the "formal title-deeds to commons", El Salvador has claimed for them a particular status in Spanish colonial law which would elevate them to the rank of "titles" of the second category, acts of the Spanish Crown directly determining the extent of the territorial jurisdiction of an administrative division; this contention will be examined at a later stage.

[p. 390] 46. ... In this connection the Chamber also observes the predominance of local features, particularly rivers, in the definition of the agreed sectors, and considers that given the task of delimitation, it is entitled and bound to have an eye to the topography of each land sector. When therefore the very many instruments cited, even after minute examination, are found to give no clear and unambiguous indication, the Chamber has felt it right similarly to take some account of the suitability of certain topographical features to provide an identifiable and convenient boundary. The Chamber is here appealing not so much to any concept of "natural frontiers", but rather to a presumption underlying the boundaries on which the uti possidetis juris operates. Considerations of this kind have been a factor in boundary-making everywhere, and accordingly are likely, in cases otherwise dubious, to have been a factor also with those who made the provincial boundaries previous to 1821.

[pp. 394-395] 54. ... In the absence of legislative instruments formally defining provincial boundaries, not only the grants to Indian communities but also land grants to private individuals afford some evidence which might indicate where the boundaries were thought to be or ought to be. Titles of the kind under discussion were granted, following enquiries and surveys by the authorities of a particular province, by the Audiencia of the Kingdom of Guatemala, and both Parties have emphasized to the Chamber the strict respect for limits of territorial jurisdiction which was required of servants of the Spanish Crown. There must be a presumption that such grants, for jurisdictional reasons and for reasons of administrative convenience, would normally avoid the straddling of an existing, established, and working boundary between different administrative authorities. And indeed where the provincial boundary location was doubtful - as could well be the case in often partially explored country - the common boundaries of two grants by different provincial authorities could well have become the provincial boundary. The Chamber will therefore consider the evidence of each of these grants on their merits in each of the sectors and in relation to other arguments, but will not treat them as necessarily conclusive.

55. At the time of the independence of the two States, much - but not all - of the land making up the territory of the administrative units to which they succeeded had thus been the subject of grants of various kinds by the Spanish Crown, either to Indian communities or to individuals. These are the títulos of which so much has been made in argument. The remaining land in the relevant Spanish colonial provinces remained in the ownership of the Crown, and fell into the category of "crown lands", tierras realengas. In the same category fell, as the Parties agree, land which had been granted to an Indian community which had ceased to exist, like that of San Miguel de Sapigre, discussed in relation to the boundary in the fifth sector. The Parties agree that such land was not however unattributed for purposes of administrative control and jurisdiction, but appertained to the one province or the other, and accordingly passed, on independence, into the sovereignty of the one State or the other. The absence of any specific grant of the land, for which a survey would have been effected, merely makes it more difficult to ascertain the position of the provincial boundary in areas of this kind.

56. There is one further problem concerning the grants or titles which requires mention; and that is how far so-called "republican titles", grants made after independence, in the time of the Federal Republic of Central America, 1821-1839 and thereafter, may be considered as evidence of the 1821 boundary. This question has arisen as an issue between the Parties in more than one sector of the land boundary, as will appear below. There seems to the Chamber to be no sensible reason to reject the whole category of these grants as ecidence just because they are subsequent to 1821. Such republican titles, particularly those granted in the years immediately following independence, may well provide some evidence of what the position was in 1821, and both Parties have offered them as such. The Chamber will, therefore, consider republican titles on their merits, as possible evidence of the uti possidetis juris position in 1821, wherever they have been pleaded as such by the Parties.

[p. 396] 58. The factual considerations which El Salvador has brought to the attention of the Chamber fall into two categories. On the one hand, there are arguments and material relating to demographic pressures in El Salvador creating a need for territory, as compared with the relatively sparsely populated Honduras; and on the other the superior natural resources (e.g., water for agriculture and hydroelectric power) said to be enjoyed by Honduras. On the first point, El Salvador apparently does not claim that a frontier deriving from the principle of the uti possidetis juris could be adjusted subsequently (except by agreement) on the grounds of unequal population density, and this is clearly right. It will be recalled that the Chamber in the Frontier Dispute case emphasized that even equity infra legem, a recognized concept of international law, could not be resorted to in order to modify an established frontier inherited from colonization, whatever its deficiencies (see I.C.J. Reports 1986, p. 633, para. 149). El Salvador claims that such an inequality existed even before independence, and that its ancient possession of the territories in dispute, "based on historic titles, is also based on reasons of crucial human necessity". The Chamber will not lose sight of this dimension of the matter; but it is one without direct legal incidence. For the uti possidetis juris, the question is not whether the colonial province needed wide boundaries to accommodate its population, but where those boundaries actually were; and post-independence effectivités, where relevant, have to be assessed in terms of actual events, not their social origins. As to the argument of inequality of natural resources, the Court, in the case concerning the Continental Shelf (Tunisia/Libyan Arab Jamahiriya), took the view that economic considerations of this kind could not be taken into account for the delimitation of the continental shelf areas appertaining to two States (I.C.J. Reports 1982, p. 77, para. 107); still less can they be relevant for the determination of a land frontier which came into existence on independence.

[p. 399] 62. ... What the Chamber has to do in respect of the land frontier is to arrive at a conclusion as to the position of the 1821 uti possidetis juris boundary; to this end it cannot but take into account, for reasons already explained, the colonial effectivités as reflected in the documentary evidence of the colonial period submitted by the Parties. The Chamber may have regard also, in certain instances, to documentary evidence of post-independence effectivités when it considers that they afford indications in respect of the 1821 uti possidetis juris boundary, providing a relationship exists between the effectivités concerned and the determination of that boundary.

[p. 401] 67. There has also been some argument between the Parties about the "critical date" in relation to this dispute. The principle of uti possidetis juris is sometimes stated in almost absolute terms, suggesting that the position at the date of independence is always determinative; in short, that no other critical date can arise. As appears from the discussion above, this cannot be so. A later critical date clearly may arise, for example, either from adjudication or from a boundary treaty. Thus, in the previous Latin American boundary arbitrations it is the award that is now determinative, even though it be based upon a view of the uti possidetis juris position. The award's view of the uti possidetis juris position prevails and cannot now be questioned juridically, even if it could be questioned historically. So for such a boundary the date of the award has become a new and later critical date. Likewise there can be no question that the parts of the El Salvador/Honduras boundary fixed by the General Treaty of Peace of 1980 now constitute the boundary and 1980 is now the critical date. If the uti possidetis juris position can be qualified by adjudication and by treaty, the question then arises whether it can be qualified in other ways, for example, by acquiescence or recognition. There seems to be no reason in principle why these factors should not operate, where there is sufficient evidence to show that the parties have in effect clearly accepted a variation, or at least an interpretation, of the uti possidetis juris position.

[pp. 640-642 S.O. Torres Bernárdez] 21. A few remarks on the question of effectivités are now in order with a view to clarifying further my position on the very concept of the uti possidetis juris of the Spanish-American Republics and other possible applicable principles or rules of international law. There has been quite a lot of confusion at the current proceedings between "applicable law", "argument" and "evidence", the statement in the 1986 Judgment of the Chamber of the Court in the Frontier Dispute (Burkina Faso/Republic of Mali) case quoted in paragraph 61 of the reasoning of the Judgment being the object of various interpretations.

22. To a certain extent it may be said that both Parties agreed that in the case of the "land boundary dispute" the uti possidetis juris should prevail over the effectivités, without prejudice, of course, to the different positions adopted by them on the kind of evidence they might rely upon to prove the 1821 uti possidetis juris situation and the question of the relationship of Article 26 of the Peace Treaty and Article 5 of the Special Agreement. The Parties, however, failed to define with any degree of precision the effectivités concept they had in mind. In fact, they have referred to various possible kinds of effectivités, within quite different legal contexts. A distinction which should, however, be always borne in mind is that between the so-called effectivités coloniales and the State's effectivités. This distinction is made in the aforesaid 1986 Judgment on the Frontier Dispute (Burkina Faso/Republic of Mali) case, in which the Chamber of the Court refers, first, to the "colonial effectivités" in order to describe the conduct of the colonial authorities as proof of the effective exercise of territorial jurisdiction during the colonial period and, secondly, to the effectivités as effective possession and/or administration by a State other than the one possessing the title or irrespective of that title.

23. The first of these two kinds of effectivités does not give rise to any norm of international law. It could only be an element of interpretation or confirmation of the uti possidetis juris, an element related to the testing of that principle in concrete situations. The second kind of effectivités mentioned, namely effective administration by a State other than the one possessing the uti possidetis juris title or irrespective of title, may be relevant to the identification of the "applicable law". The "principle of effectiveness" may indeed, other circumstances concurring, be at the origin of territorial rights. Thus it cannot be altogether excluded a priori that such effectivités could be of some relevance also to the definition of the law applicable to the case. What seems to me, however, a legal impossibility is a simultaneous application of the uti possidetis juris principle of the Spanish-American Republics and of a rule of international law construed upon the basis of the concept of "State effectivités".
24. In this respect, the Judgment, while distinguishing the above-mentioned matters correctly at the level of principle, is not immune to a certain degree of confusion through failing to make a clear-cut distinction between admissible evidence under the applicable uti possidetis juris principle and admissible evidence when other principles or rules of international law are involved. Admissible evidence under the first and second hypotheses should have been clarified further in the Judgment in order to dispel the confusion made in the Parties' pleadings between "applicable law" and "evidence". The treatment in certain well-defined hypotheses of post-independence effectivités as possible "evidence" of uti possidetis juris rights should not be allowed to impinge, in any way, on the definition, contents and purpose of that principle as applicable between the Spanish-American Republics, including the Parties to the present case. As the Judgment has stated, the uti possidetis juris principle is essentially retrospective. It is also a principle the implementation of which is grounded, basically or mainly, in "retrospective evidence", namely in legislation or documents issued by Spanish civil or ecclesiastical colonial authorities. Such documents could be of various kinds, including as with most of those submitted in the present case documents describing the exercise of territorial jurisdictions by the Spanish colonial authorities, namely describing "colonial effectivités". The best proof of this is the very language of Article 26 of the Peace Treaty, with its reference to "documents issued by the Spanish Crown or by the Spanish colonial authorities". But Article 26 of the Peace Treaty does not mix up such "documents" with the evidence referred to in the second sentence of that Article. Both kinds of evidence are kept separately, and so they should be, because of the very definition of the uti possidetis juris principle applicable between the Parties to the present case qua Spanish-American Republics.

25. For a determination in the present case of a given uti possidetis juris situation, "post-1821 effectivités" in the nature of conduct cannot be equated with "colonial effectivités" or be treated more favourably than the cautious and qualified evidentiary treatment given to the republican land titles in the Judgment. To weigh up, at once, all the effectivités, by conduct, both pre- and post-independence, in order to arrive at a conclusion as to the position of an 1821 uti possidetis juris boundary, does not make much sense if one is applying the uti possidetis juris principle. In none of the specific hypotheses dealt with in the quoted passage of the Frontier Dispute (Burkina Faso/Republic of Mali) Judgment is there any confusion between the uti possidetis juris (with its normal and natural means of evidence) and effectivités by conduct of the State or States subsequent to their independence. In none of them are either of the said kinds of effectivités equated in evidentiary value to the colonial documents, colonial effectivités documents included, on which the implementation of the Spanish- American Republics' uti possidetis juris principle is grounded. To determine the relationship, if any, between States' post-independence effectivités by conduct and the uti possidetis juris principle in a given case it is necessary in the first place to determine the uti possidetis juris situation through colonial documents and to stop there, so far as the uti possidetis juris determination is concerned, if the indicated operation yields a reliable uti possidetis juris line. This is also, it seems to me, the meaning of the dictum of the Frontier Dispute Chamber, in the Burkina Faso/Republic of Mali African case. This is, of course, without prejudice to the evidentiary value of effectivités by subsequent State conduct for the purpose of applying a rule of international law other than the uti possidetis juris principle.

[pp. 558-559] 333. The Chamber has no doubt that the starting-point for the determination of sovereignty over the islands must be the uti possidetis juris of 1821. The islands of the Gulf of Fonseca were discovered in 1522 by Spain, and remained under the sovereignty of the Spanish Crown for three centuries. When the Central American States became independent in 1821, none of the islands were terra nullius; sovereignty over the islands could not therefore be acquired by occupation of territory. The matter was one of the succession of the newly-independent States to all former Spanish-islands in the Gulf. The Chamber will therefore consider whether it is possible to establish the appurtenance in 1821 of each disputed island to one or the other of the various administrative units of the Spanish colonial structure in Central America. For this purpose, it may have regard not only to legislative and administrative texts of the colonial period, but also to "colonial effectivités" as defined by the Chamber in the Frontier Dispute case (see paragraph 45 above). In the case of the islands, there are no land titles of the kind which the Chamber has taken into account in order to reconstruct the limits of the uti possidetis juris on the mainland; and the legislative and administrative texts are confused and conflicting. The attribution of individual islands to the territorial administrative divisions of the Spanish colonial system, for the purposes of their allocation to the one or the other newly-independent State, may well have been a matter of some doubt and difficulty, judging by the evidence and information submitted. It should be recalled that when the principle of the uti possidetis juris is involved, the jus referred to is not international law but the constitutional or administrative law of the pre-independence sovereign, in this case Spanish colonial law; and it is perfectly possible that that law itself gave no clear and definite answer to the appurtenance of marginal areas, or sparsely populated areas of minimal economic significance. For this reason, it is particularly appropriate to examine the conduct of the new States in relation to the islands during the period immediately after independence. Claims then made, and the reaction - or lack of reaction - to them may throw light on the contemporary appreciation of what the situation in l821 had been, or should be taken to have been.

[pp. 563-565] 342. As noted above (paragraph 332), El Salvador also bases its claims upon its exercise or display of sovereignty over the islands. Honduras contends that the law applicable to the island dispute does not depend on the distinction between disputes as to attribution of territory and disputes as to delimitation, but is dictated by the fact that the case is one of State succession by emancipation of colonial territories; that the applicable law is the uti possidetis juris of 1821, and not the uti possidetis de facto, or occupation followed by the peaceful and continuous exercise of State functions, since both States claim sovereignty over islands on the grounds of having succeeded to the Crown of Spain at the time of independence. The Chamber notes that the law of acquisition of territory invoked by El Salvador is, in principle, clearly established and buttressed by arbitral and judicial decisions; a classic dictum is that of the arbitrator Huber in the Island of Palmas case:

"practice, as well as doctrine, recognizes - though under different legal formulae and with certain differences as to the conditions required - that the continuous and peaceful display of territorial sovereignty (peaceful in relation to other States) is as good as a title" (United Nations, Reports of International Arbitral Awards, Vol. II, p. 839).

This was the basis for the arbitrator to decide that the island of Palmas (or Miangas) "forms in its entirety a part of the Netherlands territory" (UNRIAA, Vol. II, p. 871). Reference may also be made to the case concerning the Legal Status of Eastern Greenland before the Permanent Court of International Justice.
343. The difficulty with application to the present case of principles of law in this category is however that they were developed primarily to deal with the acquisition of sovereignty over territories available for occupation, i.e., terra nullius. Both Parties however assert a title of succession from the Spanish Crown, so that the question arises whether the exercise or display of sovereignty by the one Party, particularly when coupled with lack of protest by the other, could indicate the presence of an uti possidetis juris title in the Party so exercising sovereignty, where the evidence on the basis of documentary titles or colonial effectivités was ambiguous. An illuminating decision is the Court's Judgment of 17 November 1953 in the Minquiers and Ecrehos case. In the dispute over these islets and rocks, lying between the British island of Jersey and the coast of France, both Parties produced a number of ancient historical titles, going back to the Middle Ages; but the United Kingdom presented, as the Court found, better and more convincing evidence of exercise during the critical period of State sovereignty by the authorities of the British island of Jersey over the two groups of islets. The finding of the Court was:

"The Court further finds that British authorities during the greater part of the nineteenth century and in the twentieth century have exercised State functions in respect of the group [Ecrehos]. The French Government, on the other hand, has not produced evidence showing that it has any valid title to the group. In such circumstances it must be concluded that the sovereignty over the Ecrehos belongs to the United Kingdom." (I.C.J. Reports 1953, p. 67.)

Sovereignty over the Minquiers group was found to belong to Jersey; primarily on the basis of evidence of continuous and peaceful exercise of State power, the Court found:

"that the sovereignty over the islets and rocks of the Ecrehos and Minquiers groups, in so far as these islets and rocks are capable of appropriation, belongs to the United Kingdom" (I.C.J. Reports 1953, p.72).

344. The Court in that case did not however simply disregard the ancient titles, and decide on a basis of more recent display of sovereignty. It took care to observe that in view of the alleged titles,

"The present case does not therefore present the characteristics of a dispute concerning the acquisition of sovereignty over terra nullius" (I.C.J. Reports 1953, p. 53).

When it stated that

"What is of decisive importance, in the opinion of the Court, is not indirect presumptions deduced from events in the Middle Ages, but the evidence which relates directly to the possession of the Ecrehos and Minquiers groups" (I.C.J. Reports 1953, p. 53),

it was not assimilating the islands to terra nullius, but examining evidence of possession as confirmatory of title.
345. In the present case both Parties have argued their respective claims with regard to the operation of the uti possidetis juris on the basis, in effect, that this is a principle the application of which is automatic: on independence, the boundaries of the relevant colonial administrative divisions are transformed into international frontiers. In the first place, it should not be overlooked that Spanish colonial divisions in Spanish America did not individually have any "original" or "historic" titles, as those concepts are understood in international law. The original title belonged exclusively to the Spanish Crown, not the internal administrative subdivisions established by it; and it was equally the Spanish Crown which had sovereignty of the colonial territories. Secondly, as the Chamber's examination of the sectors of the land boundary has shown, in practice the operation of the principle is more complex. Where the relevant administrative boundary was ill-defined or its position disputed, in the view of the Chamber the behaviour of the two newly independent States in the years following independence may well serve as a guide to where the boundary was, either in their shared view, or in the view acted on by one and acquiesced in by the other (cf. paragraphs 64, 80 and 205 above). This aspect of the matter is of particular importance in relation to the status of the islands, by reason of their history.

[p. 566] 347. Thus it was not until a number of years after the independence of the two States that the question of the appurtenance of the islands of the Gulf to the one or the other became of significant import. What then occurred appears to the Chamber to be highly material. The islands were not terra nullius, and in legal theory each island already appertained to one of the three States surrounding the Gulf as heir to the appropriate part of the Spanish colonial possessions, so that acquisition of territory by occupation was not possible; but the effective possession by one of the Gulf States of any island of the Gulf could constitute an effectivité, though a post-colonial one, throwing light on the contemporary appreciation of the legal situation. Possession backed by the exercise of sovereignty may be taken as evidence confirming the uti possidetis juris title. The Chamber does not find it necessary to decide whether such possession could be recognized even in contradiction of such a title, but in the case of the islands, where the historical material of colonial times is confused and contradictory, and the accession to independence was not immediately followed by unambiguous acts of sovereignty, this is practically the only way in which the uti possidetis juris could find formal expression so as to be judicially recognized and determined.

[p. 579] 368. The conclusion at which the Chamber arrives in respect of the disputed islands is thus the following. It is the Chamber's duty, under Article 5 of the Special Agreement, to take into account the "rules of International Law applicable between the Parties, including, where pertinent, the provisions of the General Treaty of Peace". In relation to the islands in dispute, the "documents which were issued by the Spanish Crown or by any other Spanish authority, whether secular or ecclesiastical", do not appear sufficient to "indicate the jurisdictions or limits of territories or settlements" in terms of Article 26 of that Treaty, so that no firm conclusion can be based upon such material, taken in isolation, for deciding between the two claims to an uti possidetis juris title. Under the final sentence of Article 26, the Chamber is however entitled to consider both the effective interpretation of the uti possidetis juris by the Parties, in the years following independence, as throwing light on the application of the principle and the evidence of effective possession and control of an island by one Party without protest by the other, as pointing to acquiescence. The evidence as to possession and control, and the display and exercise of sovereignty, by Honduras over El Tigre and by El Salvador over Meanguera (to which Meanguerita is an appendage), coupled in each case with the attitude of the other Party, clearly shows however, in the view of the Chamber, that Honduras was treated as having succeeded to Spanish sovereignty over El Tigre, and El Salvador to Spanish sovereignty over Meanguera and Meanguerita.

[pp. 676-677 S.O. Torres Bernárdez] 96. The second element of the applicable law system put forward by El Salvador in the island dispute is the one expressed by the descriptive heading of "peaceful and continuous exercise of State authority". This is certainly a valid element deserving careful examination, because of the role played by effectiveness in international law generally as well as in decisions of international courts and tribunals on competing claims concerning territory. However, the "peaceful and continuous exercise of State authority" is not in itself a principle of international law, but a manifestation of a given unilateral conduct of the State concerned, whose eventual legal effects ought to be defined in concreto in the light of the various circumstances and, first of all, of the operating norm of international law relevant in final analysis to the said unilateral conduct. Hence, in defining the legal effects to be attached in casu to a proven "peaceful and continuous exercise of State authority", a connection between that conduct and a given norm of international law is of paramount importance. This conclusion is particularly relevant in the instant case because, as indicated, the Judgment has rejected the existence of the "historic title" invoked by El Salvador.

97. Another element that in the present context needs to be produced, in order judicially to ascertain any legal effects of the principle of effectiveness with respect to sovereignty over the islands in dispute, is the basic status of the islands under international law. This, in the present case, cannot by definition, and particularly since the uti possidetis juris principle is admitted by the Judgment as applicable law, be the status of terra nullius. This is moreover a proposition accepted, though via different arguments, by both Parties. That being so, the well-known Island of Palmas dictum to the effect that the peaceful and continuous exercise of State authority is "as good as title" is a maxim subject to caution: one needing close examination and careful analysis. Certainly, a judicial body must take cognizance of a State's presence on the ground, but the legal issue before the Chamber was one not of satisfying itself that this or that Party was present in a certain island in dispute, but of deciding the different matter of the "sovereignty" over the island concerned.

[pp.679-680 S.O. Torres Bernárdez] 103. In conclusion, the uti possidetis juris, as it operated in 1821, is the principle of international law which the Chamber had to apply, in the first place, to the "island dispute". The contents, object, purpose and proof of this principle do not change because the dispute concerns sovereignty over islands and not land-frontier delimitations. But the 1821 uti possidetis juris is not necessarily the only norm of international law that the Chamber may apply in deciding today the island dispute or any other aspect of the case. The peaceful and continuous exercise of State authority (State effectivités) over the islands in dispute invoked by El Salvador is, in the circumstances of the case, a valid legal argument when clearly proven, as in the case of Meanguera. But, State effectivités alone, particularly late effectivités, cannot confer sovereign rights over islands that, in the present case, have furthermore the status of territory "avec maître". To produce the legal effect sought by El Salvador, the proven effectivités in Meanguera need to be supplemented with or articulated around a principle or norm of international law capable of conveying territorial sovereign rights over that island. This means that, to make a judicial determination today on the sovereignty over Meanguera, it is necessary likewise to verify the conduct of Honduras during the relevant period vis-à-vis the effectivités of El Salvador in Meanguera. This conduct, in so far as it might be said to reflect an implied consent, may provide the complement that the proven effectivités of El Salvador would require in order to produce territorial sovereignty effects.

104. I agree, therefore, with the general proposition as to the relevance of the peaceful and continuous exercise of State authority invoked by El Salvador as an element of the law to be applied to the dispute over Meanguera island, as well as with the verification of the related conduct of Honduras at the relevant period. I disagree, however, with the reasoning of the Judgment in so far as it is not preceded by the same careful determination of the legal situation of Meanguera and Meanguerita from the standpoint of the uti possidetis juris as it operated in 1821. This, in my opinion, has, furthermore, had untoward consequences on the adjudication of Meanguerita, an island where El Salvador has neither uti possidetis juris rights nor proven State effectivités.

[p. 711 S.O. Torres Bernárdez] 176. The application of the "appendage" thesis to an island like Meanguerita would have been open to challenge even in cases attracting the application of the rules governing acquisition of terra nullius. To attempt to apply it in a different international law environment, namely in a case where the island concerned is a territory avec maître and does not present any abnormality from the standpoint of its geographical location, its physical features and/or its conditions for sustaining human life is, so far as I can see, totally unprecedented. Yet the Judgment does just that, on three grounds, namely (a) inconclusiveness as to the uti possidetis juris position of Meanguera in l82l on the basis of colonial titles and effectivités; (b) characterization of Meanguerita as a "dependency" of Meanguera in the sense of the relevant jurisprudence of the Minquiers and Ecrehos case; and (c) impossibility of considering that the legal position of Meanguerita could have been other than identical with that of Meanguera (paragraph 367 of the reasoning of the Judgment). I reject as unfounded these three propositions. Consequently I have voted against the corresponding operative subparagraph, which I cannot uphold in the circumstances of the present case and of the law applicable to it. El Salvador did not assert any claim to Meanguerita in l854, neither has it since taken effective possession and control of that island. That being so, it is an impossibility for Honduras to have acquiesced in the exercise of sovereignty by El Salvador on the island of Meanguerita.

[p. 589] 385. The Gulf was discovered by the Spanish navigator Andrés Niño in 1522, who named the Gulf after Juan Rodriguez de Fonseca, Bishop of Burgos, patron of his expedition, which had been organized by Captain Gil González Davila. It appears that the Spanish Crown thereafter claimed and exercised continuous and peaceful sovereignty over the waters of the Gulf, without serious or more than temporary contestation, until the three present riparian States gained their independence in 1821. For the greater part of its long, known history, therefore, the Gulf was a single-State bay, the waters of which were under the single sway of the Spanish Crown. Moreover, also from 1821 to 1839 the Gulf was under the sway of the Federal Republic of Central America of which the three coastal States were member States, along with Guatemala and Costa Rica. The rights in the Gulf of Fonseca of the present coastal States were thus acquired, like their land territories, by succession from Spain.

386. Accordingly, it is necessary to enquire into the legal situation of the waters of the Gulf in 1821 at the time of succession from Spain; for the principle of the uti possidetis juris should apply to the waters of the Gulf as well as to the land. No evidence has been presented to the Chamber suggesting that there was for these waters prior to, or at 1821, anything analogous to those boundaries of provincial sway, which have been so much discussed in respect of the land.