Measuring Compliance and the Decisions of UNCLOS Dispute Settlement Bodies

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What happens after an international court or tribunal hands down its judgment? Sir Robert Jennings once noted the irony in how detailed the business of international courts and tribunals is up to and including the rendering of a judgment, and how little we know about what follows. It is indeed a curiosity given that compliance has always been a core focus of international law. Much has been written about whether compliance is necessary for international law to serve its function; whether the reputation of international courts and tribunals are damaged when a State fails to comply with their orders. We don’t intend to wade into these debates, but in a recent study have attempted to correct the lack of knowledge identified by Sir Robert in the context of the decisions of the dispute settlement bodies of the UN Convention on the Law of the Sea (UNCLOS).

UNCLOS, which has close to 170 parties and serves as the “constitution of the oceans”, contains a detailed dispute settlement system. While UNCLOS dispute settlement has had comparatively lower use than other international dispute settlement systems (like that under the auspices of the International Court of Justice or the Dispute Settlement Body of the World Trade Organization), UNCLOS is now celebrating its 30th year of operation; a good time for reflection.

So, how are these dispute settlement bodies faring? We found that actual non-compliance could be identified in only three of the 29 decisions subject of our study. In the remaining 26 decisions, there was either some degree of compliance with the decision (21 decisions), or there wasn’t enough information to come to a conclusion (five decisions). While there is room for improvement, we think that this compliance track record reflects largely well on UNCLOS and the dispute settlement system contained within it.

Measuring different forms of compliance

One of the key issues we encountered in our study related to methodology. Drawing on Shany’s work, we were of the view that compliance was best measured where there was a shift or change in the behaviour of the State in question following the handing down of the judgment. We looked at publicly available sources (such as legislation, press releases, newspaper articles, speeches and other government documents) to determine whether that shift or change had occurred, though acknowledge the fact that many more relevant documents may not be public, or may not be in English or French and therefore inaccessible to us.

Instead of beginning with a view of compliance as a binary (a State has either complied or it has not complied), we reversed the process and let the behaviour of States teach us about how compliance can be categorised. From this process, we were able to discern five modes of compliance:

  • First, full compliance, which occurs where there is some causal link between the judicial decision and State practice. In the Hoshinmaru case, Japan instituted proceedings seeking the prompt release of a vessel flagged to it, which had been arrested by Russia. ITLOS ordered the prompt release of the vessel upon payment of a bond by Japan, which was promptly paid. Russia released the vessel the following day. We consider this to be an exemplary instance of compliance with an ITLOS judgment.
  • Second, non-compliance. Non-compliance is the opposite of compliance and occurs where the judicial decision is rejected, denounced as invalid and, importantly, there is an explicit refusal to comply at all (as opposed to a refusal to comply in part or in a manner different than what was ordered). We identified three cases of clear non-compliance: the South China Sea case, Arctic Sunrise and Duzgit Integrity. Arctic Sunrise, which concerned attempts by the Netherlands to seek the release of a vessel and its crew that had been arrested by Russia, is a rare example of an UNCLOS tribunal declaring non-compliance with its orders. The crew of the Arctic Sunrise were not able to leave Russia until 27 days after the Netherlands posted a bank guarantee in line with the Tribunal’s orders, and the vessel was not released until eight months following ITLOS’ order. At the merits phase, the Tribunal considered that this delay violated the promptness requirement of its provisional measures order. Russia was therefore non-compliant with the provisional measures decision.
  • Third, part compliance, which occurs where a State has responded to some part of the judicial decision but not others. In Barbados v. Trinidad and Tobago, which was the first maritime boundary delimitation dispute initiated under UNCLOS, the track record indicates that both States have made substantial efforts toward compliance in respect of most of the Tribunal’s operative orders. However, the States have not, as far as we are aware, come to a formal agreement for the conservation and sharing of flyingfish stocks, as ordered by the Tribunal. As such, only part of the Tribunal’s order has been complied with.
  • Fourth, good faith compliance, which occurs where a State has made some bona fide effort to comply with the judicial decision but has been unsuccessful in achieving full implementation. This form of compliance may occur where the State lacks capacity to implement the judgment, or where the dispositif is ambiguous. In Camouco, which concerned the prompt release of a Panamanian fishing vessel arrested by French authorities, there was a small but significant time lag of some three weeks between the time that Panama paid the bond ordered by ITLOS and the release of the vessel by France. This delay was, however, due to the need to have the value of the bond payable revised as a matter of domestic law by the local courts. While the operation of internal law cannot act as an excuse for delays in compliance, it is apparent that the French authorities were endeavouring to comply with the order.
  • Fifth, nominal compliance, which occurs when there have been actions that comply with the judicial decision, but compliance is undermined in some way. In Three Ukrainian Naval Vessels, which concerned an application by Ukraine for the return of vessels and servicemen detained by Russia, the vessels in question were returned to Ukraine in a sub-par condition, having been stripped of some of their features. In the circumstances, Russia could not be said to be in full compliance with the Tribunal’s orders – at most Russia could be seen to have engaged in nominal compliance.

Even with a more extended category of compliance behaviours, we acknowledge that the classification task is not always absolute and necessarily involves some amount of subjective determination. Distinguishing between good faith compliance and part compliance may not always be evident; it suggests that there is a residual aspect of the judgment that has not been addressed. Our emphasis rests on whether there was an effort to comply or whether the State(s) concerned chose not to follow up a particular order. Nominal compliance compared with good faith compliance indicates a distinction being drawn between behaviour that respects the dispute settlement process and conduct that may signal ongoing disagreement as to the respective positions of the stakeholders (either the claimant’s legal position or the tribunal’s jurisdictional determination). While not wanting to be dogmatic about the categories, what we sought to determine was that in each instance of compliance, the judgment made some difference to State conduct.

When allowing for these different forms of compliance, it can be concluded that compliance occurs more often than not in UNCLOS dispute settlement.

Findings on Compliance in UNCLOS Dispute Settlement

We found that the majority of cases of full compliance were decisions of the International Tribunal for the Law of the Sea as opposed to the ad hoc Annex VII tribunals constituted under Part XV. Whether this track record alone should sway UNCLOS parties as to which forum to select is not, however, compelling.

Other key takeaways included that, in prompt release proceedings, vessels and their crew were usually released when ordered by ITLOS. Further, we usually found compliance with maritime boundary delimitations, which may be explained by the need to generate the necessary commercial certainty to allow for resource extraction. When significant political interests are involved, such as in South China Sea, it is perhaps unsurprising to find that compliance may be less forthcoming.

Even taking these instances of non-compliance into account, we believe that recourse to UNCLOS dispute settlement nonetheless makes a difference to the pacific settlement of international disputes. It is notable that many more cases have been instituted than decisions rendered under UNCLOS dispute settlement. The very initiation of proceedings has undoubtedly had an impact on the interactions of States party to UNCLOS and on ocean governance more broadly.

Indeed, compliance with the decisions of an UNCLOS tribunal is only one aspect of post-judgment behaviour. Other outcomes we identified included modifications to domestic law or contributions to the evolution of international law. In our view, the decisions in which compliance was the least perfect – South China Sea and the cases involving Russia – have been among the most consequential in terms of clarifying the content of international law.

While compliance is not the only benchmark of success, this track record of compliance reflects well on both UNCLOS and the integrity of the dispute settlement bodies created pursuant to it. In our view, the 30th anniversary of the entry into force of UNCLOS marks the existence of a resilient and purposive dispute settlement system.

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Hendrik Mathis Drößler says

April 3, 2024

Thank you sincerely for your insightful blog post. As I'm deeply engaged in research on compliance myself, I'd like to offer some reflections on methodology, if I may.

In your discussion, you cite Shany's work, where he aptly notes that "Compliance remains an imperfect proxy for goal-based effectiveness, and the methodological difficulties of measuring even judgment-compliance – or demonstrating causation – seem insurmountable" (p.182). Shany's approach underscores the necessity of a multi-dimensional analysis to address such complexities. Do you share his perspective on this matter, or is there a specific reason for focusing solely on compliance?

Furthermore, I'd like to delve into the distinction you make regarding the challenges of implementing international judgments within domestic law and deeming it as a subtype of compliance.. From an international legal standpoint, domestic legislation cannot serve as an excuse for non-compliance (see Art. 27 VCLT, ELSI Case of the ICJ para 73, Art. 3 ARSIWA, etc.). Relying on domestic law to justify non-implementation not only demonstrates bad faith but also disregards the binding force of the judgment. For instance, Walter-Ramirez's analysis highlights how certain Latin American states strategically embed territorial boundaries in their constitutions to evade potential future territorial awards by the ICJ (see Walter Arévalo Ramírez, "Resistance to territorial and maritime delimitation judgments of the International Court of Justice and clashes with ‘territory clauses’ in the Constitutions of Latin American states" [2022] LJIL 35.1, p.185).

Moreover, in terms of methodology, there exist more recent approaches to assessing compliance than Shany's, which integrate compliance assessment as part of a broader framework. Alexandra Huneeus, for example, proposes a methodology, which inter alia to many other things, that emphasizes the temporal dimension in compliance assessment. She argues that the timing of compliance actions is crucial; an act of compliance six months after a ruling may differ qualitatively from one occurring a decade later. The Corfu-Channel Case, where it took Albania forty-five years to fulfill its obligations to the United Kingdom, underscores the significance of temporal nuances in compliance evaluation. Why not rely on more recent methodology specifically designed for compliance assessment instead of Shanys approach about overall effectiveness of an institution? (see Alexandra Huneeus, "Compliance with Judgments and Decisions" in Cesare PR. Romano, Karen J. Alter, Yuval Shany (eds), The Oxford Handbook of International Adjudication, Oxford University Press, 2013).

Furthermore, it's essential to consider post-judgment interactions between the parties, as they may establish a framework for both the timing and substance of compliance obligations.

Thank you for considering my reflections.

Warm regards,

Jack McNally says

April 5, 2024

Dear Hendrik

Thanks for your comment and for engaging with our work - we hope it is useful in your research on compliance. One of the difficulties that comes with condensing a large study into blog form is that economies need to be made and many of the items you reflect on are dealt with in some detail in the longer study (in particular, in Chapter 2).

On the multi-dimensional nature of effectiveness, we agree and certainly haven't set out to use compliance as a singular vector for effectiveness. Compliance (or non-compliance), however, has important impacts on the legitimacy of international courts and tribunals, and is therefore worth studying.

We also agree, and have endeavoured to make clear, that domestic law does not provide an excuse for non-compliance. We do, however, think there is merit in differentiating between cases where a State is actively attempting to comply with an order but compliance has been slowed due to internal judicial or legal processes.

Huneeus' work, among others, feature heavily in our discussion of compliance in the book. We agree that the timing of compliance actions is crucial; it is one of the key factors that separates the different 'categories' of compliance in our analysis.

Finally, not only are post-judgment interactions between the parties to a dispute are informative, they were the inspiration for our study generally. One of the positive impacts we discuss in the book is that post-judgment interactions between parties have often legitimised the role of international courts and tribunals in determining disputes and demonstrated how those courts and tribunals can lead to an improvement of relations between parties to a dispute.

Kind regards
Jack and Natalie

Hendrik Mathis Drößler says

April 6, 2024

Thank you immensely for your prompt response! Following the conclusion of my exam period next week, I eagerly anticipate delving into your book and looking deeper into your methodology.
Interestingly, during a recent discussion with Judge Hilary Charlesworth, who graciously visited our class last month, I got to ask her about her view on compliance studies. She shared Shanys view and doubted the utility of such studies. Nonetheless, I find myself inclined to echo your perspective. I firmly believe that comprehending the extent to which states adhere to various norms in disputed areas could significantly enhance our understanding of the efficacy of courts or tribunals in resolving such disputes. This is not merely a matter of assessing the legitimacy of laws, as states seldom contest the validity of norms (i.e. show open defiance). Rather, it pertains to their effectiveness—the "ought," as Kelsen aptly frames it— which, in turn, holds implications for the rule of law. Ultimately, different forms of international arbitration serve as indispensable means within the toolshed of states, trying to enforce the law. It’s a question about choice of effective means to induce compliance, which is in turn highly depended on the subject issue at stake and the forum chosen to solve it. Whether through what Born describes as second-generation tribunals, traditional inter-state dispute settlement mechanisms like those of the Tribunal for the Law of the Sea, or bespoke party-tailored dispute resolution bodies, or even diplomatic channels, these avenues collectively contribute to maintaining the adherence to the legal order. A nuanced comprehension of which "tools" are most effective for resolving specific areas of disputes, I believe, has the potential to cultivate and fortify the rule of law.

Kind regards from Groningen