Customary International Law Symposium: Rules Everywhere and At All Times (Whether You Like It or Not)

[Jean d’Aspremont is the Chair in Public International Law at the University of Manchester.]

That international lawyers constantly feel a need to revisit their doctrinal fundamentals is no sign that the international legal discipline is running out of steam (and out of inspiration). Even if international lawyers feel the world is crumbling in front of them and demanding urgent interventions, there is great merit in re-examining, like Professor Monica Hakimi does in her recent piece on ‘making sense of customary international law’, the loose ends of customary international law. Such fundamental debates may even be the manifestation of a self-confident discipline that is not afraid of shedding light on the very wobbly constructions it has heavily relied on for more than a century. Actually, Professor Hakimi should be praised, not only for the stellar piece of scholarship she has produced on customary international law, but also for regularly bringing such fundamental questions to the fore of the scholarly arena notwithstanding the overwhelming temptations to over-specialize, create new niches, take refuge in esoteric interdisciplinarity, generate new forms of sophisticated empiricism, indulge in scholarly journalism, etc.

Once we agree that revisiting the foundations of customary international law has remarkable disciplinary merit and that Professor Hakimi’s piece is an impressive piece of scholarship, we can start speaking frankly. In this case, speaking frankly does not mean awarding marks in the form of right or wrong. Actually, I have always found it deeply ironical that self-declared perspectivist international lawyers pass final truth judgement on one another’s argument in the form of right or wrong. As far as I am concerned, I do not think that anything Professor Hakimi writes in her piece is actually right or wrong. It might simply be convincing or unconvincing. For that reason, speaking frankly only means telling a much esteemed colleague that her attempt to fix the loose ends of customary international law is not convincing. This is what I will do in the next paragraphs.

In her article, Professor Hakimi takes issue with what she calls the “rulebook” approach to customary international law whereby arguments on customary international law are supposedly constrained by (and meant to respond to) pre-existing rules about custom-ascertainment. Her position could be described as a rejection of the rulism (that is the thinking in terms of rules) that dominates legal thought and practice about the ascertainment of customary international law. Her argument, that echoes earlier criticism of rule-based thinking about the sources of international law, is important, if not compelling. Indeed, it seems difficult to deny that rulism – just like so many other constructions in international legal thought and practice – cannot meet is own criteria of validity. As is persuasively argued and demonstrated by Professor Hakimi, there cannot be rules, let alone customary rules, on the ascertainment of customary international law. And yet, speaking frankly, I cannot help remaining unconvinced by her overall anti-rulist argument. Instead of formulating linear objection as one is expected to do in this sort of exercice, I would like to make 5 observations which, taken together, should suffice to sketch out the various dimensions of my own incredulity towards Professor Hakimi’s fine argument.

An epistemological remark. It is interesting that a great deal of the international legal scholarship to which I have access reads as if international lawyers had one day left their study to take a walk in the world out there, spotted a problem (often in the form of a puzzle, uncertainty or unclarity) across the river along which they were walking, came back home, pondered over a new construction fixing the problem (and clarifying all puzzles, uncertainties and unclarities) they had spotted, and then went on to publish a neat text describing their problem-solving and elucidatory invention. The result is an international legal scholarship where diagnoses about world problems and scholarly therapies always confirm one another, making one another look natural and self-evident. This genre has been flourishing in relation to customary international law. Professor Hakimi’s piece whose title is an explicit reference to such problem-solving and elucidatory agenda, follows that literary tradition.

A defence of the International Law Commission (yes, this is possible!). Having myself taken issue with the work of the International Law Commission in no mild terms and on multiple occasions, I hope I can defend the Commission without being suspected of complacency. In her piece, Professor Hakimi is prompt to arraign the International Law Commission for the rulism that dominates its work on the identification of customary international law. I believe that her charge is excessive. As early as 2013, the International Law Commission made it clear that its work was prejudging neither the nature of the criteria of custom-ascertainment, nor the process of formation thereof. It is even its ambition not to look into the nature of the criteria of custom-ascertainment and the formation thereof that led the Commission to rephrase the way in which it describes its own work, from “formation and identification of customary international law” to “identification of customary international law”.

A gentle note of caution. Professor Hakimi seeks to offer an anti-rulist approach to customary international law whereby she redirects the identification of custom to a question of “salience”. From her perspective, what matters is to what degree a particular normative position is law, in what settings it is held as such and for whom it does have legal effects. Whilst I do believe, like Professor Hakimi, that the doctrine of customary international has been articulated around very cheap self-grounding constructions, I cannot help fretting at her invitation that lawyers defer to the effects of norms for custom-ascertainment purposes. I am sure that many lawyers in the current White House (are there any?) would relish being told that the existence of international legal rules depends on actual salience among those actors on whom such rules are supposed to be binding. At a time of banalized post-truth delinquency, I think international legal scholars should be careful not to give such easy ammunition to those for whom decency no longer means anything. 

An ontological observation. Throughout her paper, Hakimi constantly refers to the “day-to-day operation of customary international law”, the “practice of customary international law”, the “real world”, the idea of “raw data”, etc. One of her charges against the rulebook approach is precisely that rulism is “dissociated” from such real world. This means that, for Professor Hakimi, there is thus the law (and the scholarly constructions that gravitate around it) on the one hand and the world on the other hand. This is a form of ontological dualism that is very common in international legal scholarship whereby international law and the world to which international law is applied are strictly distinguished. Such common ontological dualism usually comes with the granting of descriptive and normative superiority (as well as extra social capital) to anything (and anyone) associated with the world. Whilst I must make clear that I find such ontological dualism rather simplistic, this is not a point I want to pick up here (it is a lost battle anyway). I am just surprised that Professor Hakimi espouses such crude ontological dualism so wholeheartedly. I had the impression that, in her earlier work, she had put more emphasis on the extent to which the world to which international law applies is a performance of international law itself, which is much closer to my own position.

Last but not least. I believe that Professor Hakimi is not really criticising the rulism of the doctrine of customary international law itself but the presumption of materiality of the rules about the ascertainment of customary international law. Said differently, what she is taking issue with is not the thinking in terms of rules about the ascertainment of customary international law itself but the material inexistence of such rules. Indeed, she keeps saying that all those who espouse a rulebook approach fail to see that there is nothing like rules about customary law and that such rules simply do not exist. For Professor Hakimi, international lawyers should not be thinking in terms of rules as long as there are no material expressions of such rules in the world out there. This means that, for her, the categories of legal thought should follow worldly materiality. Her posture is not unheard of and, once again, echoes a common pattern of thought in the international legal literature whereby a norm comes with a legal form, a negotium comes with an instrumentum, a signified comes with a signifier, etc. As far as I am concerned, this postulation of a necessary correspondence of the rule with a material artefact constitutes a rather intriguing move, not least in the case of customary international law. In my view, requiring that the rules of international law demonstrate some materiality to be rules reduces dramatically what international law can be and can do. If we were to reduce international law to an artefact, I believe that there is little that international law would ever achieve in the world. I believe that Professor Hakimi realizes it, for she seems to recant such principled materialism in the last paragraphs of her piece when she writes that law “does all sorts of things” and “structure[s] a certain kind of argumentative practice”. In my view, her last-minute backtracking proves more convincing than her principled materialism. The rules of international law can do all what they do, even establishing action-guiding prescriptions, without necessarily having any kind of material existence other than being in the discourse.

Where do I stand? I have now spoken frankly and mentioned five reasons why I am not entirely convinced by the stellar piece of research produced by Professor Hakimi. The foregoing does however not say anything about where I stand and how I answer the important question which Professor Hakimi has put forward and which certainly warrants reflection. Although I have earlier felt the very same unease as Professor Hakimi towards the artifice of rules, and especially the idea of secondary rules, I have come to believe that my own earlier worries missed the point. Indeed, I have grown convinced that there is no way out of the rule. The rule – not as a legal artefact but as a sign – is everywhere. Indeed, the rule provides the signs through which the world, the practice, the space, the past, the context, the norms, the actors, the deeds, the inaction, etc. are constituted, cognized, perceived, apprehended and experienced. In that sense, the “real world” – which Professor Hakimi repeatedly refers to – is, for international lawyers, a world saturated with rules. This concretely means that the practice of States which Professor Hakimi continuously invokes, and in particular its content, consistency, inconsistency, variety, and, more generally, all what States can possibly do are constituted, cognized, perceived, apprehended, and experienced through rules. In other words, there cannot be any kind of practice without a rule being presupposed in the first place. Even the absence of practice is always an absence constituted, cognized, perceived, apprehended, and experienced through a rule. Put simply, there is just nothing outside the rule.

In sum, rules have no material existence and yet international lawyers cannot escape them. This is no grim state of affairs. After all, thanks to its omnipresent and world-saturating rules, international law achieves so much with so little. This should provide another boost to the discipline’s self-confidence (which could prove welcome these days). And yet, the fact that international law achieves so much with so little is the very reason why international lawyers should constantly remain alert to what their omnipresent and world-saturating rules do. Rules enable but they also govern, discriminate, devastate, and repress. The point is thus not to go after rulism but to perpetually scrutinize what rules do. Anti-rulism – which I once also succumbed to – is an unnecessary distraction from something far more important.