Please Mind the Gap: A Venn Diagram Story of Method in International Law

by | 31 Jan 2023

Working in international law as government lawyers for many years, method was not a day-to-day concern for us. Although we dealt daily in the ‘sources’ of international law, the question of ‘method’ was not part of the picture.

The day-to-day job of a government lawyer demands an answer to what the law is. What law applies to a crime occurring on a cruise ship in a particular location? What is required to justify intervention in a particular conflict on the grounds of collective self-defence? Do certain changes to domestic social security laws engage international human rights obligations? 

Discovering what the law is entails a doctrinal inquiry, following the same process that would be used by any good student in an undergraduate international law class—reference to the sources of international law recognised in Article 38 of the ICJ Statute: custom, treaties, judicial decisions, the writing of eminent commentators. Essentially, reference to the law in the books. 

But government lawyering also necessarily entails engagement with practice—principally that of one’s ‘client’ State, but also of other States. Somewhere along the way, we realised that the law we were seeing ‘in the books’—in academic writing and judicial decisions—did not always align with the law we saw in practice, sometimes with important differences. This is a story about how a gap between ‘law in the books’ and ‘law in practice’ became increasingly visible to us, and how – despite using classical tools of international law – we retained a sense of being embarked on a somewhat radical enterprise.

Please mind the (legal and practical) gap

For example, scholars commonly assert that under the 1982 United Nations Convention on the Law of the Sea (the LOSC), the baseline—the starting point from which a State’s maritime zones are measured under the law of the sea—ambulates with the coastline. But it would be highly impractical for States to manage a constantly mobile marine jurisdiction. It seemed more likely that States would take a ‘set-and-forget’ approach than spend time and resources continuously surveying and updating their baseline, and the maritime zones that it generates. If that was indeed the case, could it be that so many States were acting at variance with this core rule in the international law of the sea—or were the books overlooking something?  

In the fisheries context, it was startling to realise that as late as 2014, the International Tribunal for the Law of the Sea was being asked in the Virginia G case to decide whether or not a coastal State’s sovereign rights over ‘fishing’ in the 200 nautical mile exclusive economic zone (EEZ) included the right to regulate refuelling of fishing vessels, when this was already widely regulated under national laws and in regional and international instruments. Happily, the Tribunal’s decision ultimately validated this practice, but its reasoning—that such activities were regulated by ‘several States, not only in the West African region, but also in some other regions of the world’—seemed a rather incomplete depiction of the role of State practice.

Once we started looking, we found this reinforced in other places. For example, the Arbitral Tribunal’s decision in the South China Sea Arbitration included some far-reaching statements about the characteristics of an ‘island’ under Article 121 of the LOSC, without any reference to the extensive State practice regarding the features which have received widespread acceptanceunder this Article. Another obvious example is found in recent judgment of the International Court of Justice  on Alleged Violations of Sovereign Rights and Maritime Spaces in the Caribbean Sea, in which the Court confirmed the customary status of Articles 7 and 303(2) of the LOSC, similarly without any consideration of State practice (as noted, at least with respect to Article 7, in the dissenting opinion of Judge ad hoc Mcrae).

Method as a research origin story

These examples raised some difficult questions for us. It seemed that it wasn’t simply a case of the law ‘in the books’ being a little behind the ‘law in action’ and in need of updating, but more a question of substantive dissonance—a meaningful difference between the content or even the intent of the law as described in the literature and jurisprudence, and as understood and practiced by States in reality. And even beyond that, a failure to meaningfully consider the substance or extent of State practice.

Is it because it’s just too hard? With 193 UN Member States, there is a lot of practice (in a lot of languages) to consider, making a comprehensive review a challenging task. Should we just accept that international law is a Venn diagram, where the law in the books and the law in practice exist in separate but overlapping circles? Or is there a way to better align these circles?

Like a little Venn diagram of our own, we both (separately) departed our government jobs to undertake PhDs, hoping to unravel this mystery through a very simple and yet rarely used research methodology: a comprehensive examination of State practice, undertaken by reference to the rules of international law, and analysed inductively to articulate and justify a conclusion about the contemporary state of the international law in relation to baselines (Frances) and coastal State jurisdiction over living resources in the EEZ (Camille).

Integrating practice into law

The method underpinning our research was simple: to gather the material of the law as it is revealed in the practice of States, and apply the relevant legal rules to establish its legal effect. 

The practical conduct of this was more difficult, and involved extensive desktop and internet research to obtain authentic (and comparable) material from as many States as possible. For Frances, this meant examining the maritime zones legislation of all 153 coastal States, while Camille analysed legislation relating to fisheries from 145 coastal States. And since not all the material was in English, we relied on Google translate and other software, and on our experience as government lawyers in statutory interpretation.

In adopting this method, we prioritised integrating State practice into the identification and interpretation of international law, in pursuit of idea that the best, and most accurate, understanding of the law is found in the common ground of this overlap.

At one level, this is simply classical doctrinal method, applying the basic canons of international law: a single combined operation to arrive at an ‘authentic interpretation’ of treaties under the Vienna Convention on the Law of Treaties, and considering the evidence of common, concordant and consistent State practice in the identification of customary international law.

And yet the undertaking retained a sense of the radical and unorthodox.  This partly reflected our awkwardness in interpreting laws from other countries and legal traditions, building meaning from varied materials to assemble ‘evidence’ of global State practice.  It was also because the prominence we gave to such evidence contrasted our awareness that State practice is routinely ignored or under-emphasised in the jurisprudence and scholarship.  And perhaps most of all, we retained a sense of the radical because some of the findings reached by the systematic application of this method were literally unsettling, in that they challenged the conclusions ‘in the books’.

So what? What joy can this method bring?

Perhaps, as government-lawyers-turned-academics, we are overly sensitive to the importance of State practice. But surely embracing a legal method based on a wider and deeper examination of State practice would have significant benefits.

First, it is a genuine reflection of international law method, in the sense exhaustively described by the International Law Commission in the draft conclusions on the identification of customary international law and on subsequent agreements and subsequent practice in relation to the interpretation of treaties. 

Second, it can help to provide a positive answer to Anthea Roberts’ now famous question ‘Is international law international?’ by ensuring international law ‘in the books’ takes into account practice from different regions, languages and legal traditions.

Third—perhaps controversially, but also critically—this method could lead to a more accurate and integrated understanding of the law, and to better alignment of the two circles with a goal of reaching the point where there is only one answer to the question: what is the law?

*Frances Anggadi is a PhD candidate (Sydney Law School) and Marine Studies Institute researcher at the University of Sydney.

Dr Camille Goodman is a Senior Lecturer at the Australian National Centre for Ocean Resources and Security (ANCORS) at the University of Wollongong, and a Visiting Fellow at the ANU College of Law, Australian National University, Canberra.


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