Exercise of Jurisdiction or Admissibility?
Delimitation of Outer Continental Shelf (Part II)

By Professor Bjørn Kunoy
Published on 1 June 2023

Conflicting approaches in Jurisprudence

With the recent judgment of the Special Chamber in Mauritius v. Maldives there are now five decisions addressing the merits of questions regarding the delimitation of the outer continental shelf lacking CLCS recommendations. Another dispute is currently pending on the merits. These decisions show five different approaches as to whether the delimitation of the outer continental shelf lacking CLCS recommendations concerns the exercise of jurisdiction or admissibility. The recent decision of ITLOS in Mauritius/Maldives adds new elements and addresses the ´inconsistent jurisprudence` (p. 1) on this matter.

First, in Bangladesh/Myanmar ITLOS approached the question as one concerning the exercise of jurisdiction rather than admissibility. According to ITLOS, where there is no CLCS recommendation the exercise of jurisdiction to delimit the outer continental shelf depends on whether there is ‘significant uncertainty’ as to the existence of either party’s claimed entitlement (para 443). ITLOS established a relatively high benchmark for not exercising jurisdiction. According to ITLOS, it ´would have been hesitant to proceed with the delimitation` (para 443) of the areas beyond 200 M had it concluded that there was significant uncertainty about the existence of a continental margin in the area in question. The delimitation notwithstanding the lack of CLCS recommendations is framed as a decision to refrain from the ‘exercise of its jurisdiction over the dispute.’ Nowhere is the question seen as an admissibility test (para 391).

Second is the approach of the Annex VII arbitral tribunal in Bangladesh v India. The arbitral tribunal did not consider relevant the fact that CLCS had not made its recommendations for the purpose of delimiting the overlap of outer continental shelf entitlements. To ground its approach, the arbitral tribunal relied on the concept of a single continental shelf to which the importance of coastal projections to areas beyond the 200 M distance line is the same as to areas within the 200 M distance line. Treating these areas differently would be impermissible under Article 83, which does not allow any ´such distinction` (para 77) to be made. Considerations regarding admissibility or whether there were circumstances that would call for it to decline the exercise of its jurisdiction were not given any consideration. The merits of that decision on those particular points must be seen questioned in light of the observations of President Joan Donoghue and Judge Xue in their respective separate opinions in Maritime Delimitation in the Indian Ocean (Somalia v. Kenya) (para 12) (para 11).

Third is the approach of the International Court of Justice (ICJ) in the Territorial and Maritime Dispute (Nicaragua v. Colombia) (NICOL) and in Question of the Delimitation of the Continental Shelf between Nicaragua and Colombia beyond 200 M from the Nicaraguan Coast (NICOL II). The ITLOS Special Chamber also partly followed this approach in Ghana/Côte d´Ivoire. A plea to delimit the outer continental shelf, lacking CLCS recommendations, is admissible provided that States fulfil their procedural obligation under Article 76(8) of UNCLOS. In its judgment on merits in NICOL, the ICJ established that it could not uphold the final submission I(3), in which Nicaragua requested it to define ´a continental shelf boundary dividing by equal parts the overlapping entitlements to a continental shelf of both Parties` because Nicaragua ‘has not established that it has a continental margin that extends far enough to overlap with Colombia´s 200 [M] entitlement’ (para 129). In NICOL II, the parties disputed what exactly the Court decided in NICOL. In NICOL II, the question was whether a State’s submission to the CLCS is sufficient for, to rely on the expression in NICOL, establishing that a continental margin extends into an area claimed by a third State, or whether a recommendation of the CLCS was necessary. By the President’s casting vote, the ICJ concluded that what it had meant in NICOL was that delimitation of the outer continental shelf ‘was conditional on the submission by Nicaragua of information on the limits of its continental shelf beyond 200 nautical miles, provided for in paragraph 8 of Article 76 of UNCLOS, to the CLCS’ (para 85). The ICJ determined that a CLCS recommendation ‘is not a prerequisite` for the delimitation of the continental shelf beyond 200 nautical miles’ (para 114) and therefore that Nicaragua’s application was admissible (para 115). Consequently, by fulfiling the procedural obligation in Article 76(8) of UNCLOS, Nicaragua has ´established that it has a continental margin that extends far enough to overlap with Colombia´s 200 [M] entitlement’ (para 129). Accordingly, assuming that in the forthcoming ICJ partial judgment in NICOL II, it would conclude that under customary international law outer continental shelves may extend into and overlap with continental shelves within 200 M, it would be difficult to accept the proposition that the ICJ could decline to exercise its jurisdiction on grounds that relate to whether the applicant has demonstrated entitlement. This arises by the fact that its finding in regard to above-mentioned final submission I(3) was to be understood such that coastal States, in casu Nicaragua, had ´established that it has a continental margin that extends far enough to overlap with Colombia´s 200 [M] entitlement` upon the fulfilment of the procedural obligation in Article 76(8), and only therefore was the submission of Nicaragua in NICOL II considered ´admissible` (para 115). A similar reasoning appears also in Ghana/Côte d´Ivoire. Ghana had fulfiled its procedural obligation to submit data to the CLCS and had also received its recommendations of the CLCS. While Côte d’Ivoire had made a submission, its consideration was pending upon the reading of the judgment. Yet, after stating that the ´Special Chamber can delimit the continental shelf beyond 200 nm only if such a continental shelf exists` it concluded that it ´ha[d] no doubt that a continental shelf exists for Côte d’Ivoire` (para 491) upon which it concluded that the ´relevant submissions [of the Parties] are admissible` (para 495).

A fourth approach is the one in the judgment on preliminary objections Somalia v. Kenya. In that judgment, the ICJ appeared to revise its position stated in NICOL II. In Somalia v. Kenya, the ICJ found that the absence of CLCS recommendations ‘does not necessarily prevent’ it from delimiting the outer continental shelf ‘in appropriate circumstances’ (para 94). Somalia v. Kenya suggests there may be circumstances that could prevent the exercise of jurisdiction to delimit the outer continental shelf, even though the Court may have jurisdiction and the relevant application being admissible. It is apparent that an amalgam is made between a decision to decline the exercise of jurisdiction and a finding of inadmissibility. Thus, the reservations expressed in the judgment on preliminary objections in Maritime Delimitation in the Indian Ocean (Somalia v. Kenya) appear clearly related to the admissibility of such submissions, rather than an exercise of jurisdiction, although it would follow from the finding in NICOL II that the submission of Somalia would necessarily be admissible. From the above observations of the ICJ, the proposition is put forward that it may have been more suitable to order the admissibility issue to be joined to the merits, rather than creating a situation in which jurisdiction is established and a determination of admissibility, from which it unequivocally can be said that it necessarily follows from such a determination that establishment of entitlement is determined, but notwithstanding to possibly be followed with a third decision to refrain from the exercise of jurisdiction on matters that may relate to the uncertainty whether entitlement to outer continental shelf areas is established.

The fifth approach appears in the judgment on the merits in Mauritius/Maldives. The Special Chamber departed from the ICJ’s reasoning in NICOL II by stating that it ‘does not consider that there is any rule requiring that a submission be made prior to the institution of delimitation proceedings’ (para 377), whereas the fulfilment of the procedural obligation under Article 76(8) was in NICOL II spelled out as an admissibility test. It is clear that the delimitation of claimed overlaps of outer continental shelf entitlement is not dependent upon any procedural requirement, but perhaps rather, to rely on the expression of Judge Heidar in his recent Declaration, is a ‘substantive requirement’ (para 9). Not surprisingly, the Special Chamber relied on Bangladesh/Myanmar. Following that judgment, it applied the ‘significant uncertainty’ (para 433) formula to decide whether to exercise jurisdiction to delimit the overlap of outer continental shelf claims between Mauritius and the Maldives. The Special Chamber added that it ‘can only defer the consideration of the exercise of its jurisdiction if it has in the first place assured itself that it has jurisdiction’ (para 337). Yet, what appears in the Northern Cameroons and also in the Nuclear Tests case is that to decline the exercise of jurisdiction can be made ´[w]hether or not at the moment the Application was filed there was jurisdiction in the Court to adjudicate upon the dispute` (p. 38). It would appear that the decision of the Special Chamber more appropriately could have been considered in the form of a finding of inadmissibility, i.e. that the submission of Mauritius asking the Special Chamber to delimit the overlap of claimed entitlements was inadmissible in the presence of significant uncertainty surrounding the question whether the data in support of its proposed outer limits of continental shelf were sufficiently persuasive. Yet, the Special Chamber had already in its judgment on preliminary objections of 2021 determined that the submission of Mauritius, requesting the Special Chamber to delimit the overlapping continental shelf entitlements, including areas beyond 200 M from the baselines, was admissible. Yet, upon the reading of the judgment on preliminary objections on 28 January 2021, Mauritius had not even submitted preliminary information indicative of the outer limits north of Chagos, which was only submitted to the CLCS on 24 May 2021, to include claimed entitlements north of Chagos (see Fig. 4). This demonstrates a difference with the approach of the Court in NICOL I in which it determined that the final submission I(3) of the applicant, requesting the Court to delimit those parts of the overlap that were beyond 200 M from the mainland of the applicant but within the 200 M zone from the mainland of the respondent, was inadmissible because the applicant had not fulfilled the procedural obligation in Article 76(8) of UNCLOS, a prerequisite for admissibility – in the mind of the Court. It is difficult to understand the rationale for that decision of the Special Chamber in Mauritius/Maldives, in so far concerns its statement that the finding of admissibility also relates to the areas beyond 200 M as a finding of admissibility appears completely detached of any fulfilment of the procedural obligations in Article 76(8); rather leaving it for the merits to decide on whether to uphold the relevant submission of Mauritius notwithstanding a prior determination of admissibility.

Concluding Remarks

The delimitation of the outer continental shelf lacking CLCS recommendations remains subject to different approaches, although it appears that the formula applied by ITLOS in Bangladesh/Myanmar is gaining traction. With the caveat in Somalia v. Kenya and the recent decision of the Special Chamber in Mauritius/Maldives, it appears now that the decision as to whether to delimit overlaps of claimed outer continental shelf entitlements in the absence of CLCS recommendations will be incumbent upon, to use the expression of Judge Heidar, a ´substantive requirement`. It remains to be seen whether in effect the ICJ will follow this approach. In any event, and of equal interest, is whether the ICJ could decline the exercise of its jurisdiction in such disputes, where it is duly seized and a determination is made on the admissibility of a submission to delimit outer continental shelf entitlements. This arises as the determination of admissibility in the judgment on preliminary objections in NICOL II was made on grounds that by fulfiling the procedural obligation in Article 76(8) of UNCLOS, it was considered established that the continental margin extends into the continental shelf of the other disputing party. Such facts being ´established` makes it difficult to conceive which circumstances could justify the ICJ to decline the exercise of jurisdiction on grounds that would appear to relate to uncertainties as to the existence of entitlement to the disputed area. One is inclined to rely on an expression of Gerald Fitzmaurice, albeit in another context, ´a claim which would and could only have the outcome described in the Judgment […] must itself be regarded as inadmissible` (p. 101).