Costumary international law in a global community: tailor made?

• Author: Orrego Vicu

The growing trend to consider as customary law rules devised to support preferences and arguments, that cannot otherwise qualify as law, is leading to serious doubts about the real meaning of international law. This article examines the reasons behind this phenomenon and reflects on means for strengthening the traditional requirements of customary international law so as to ensure that proper law is made. It notes that customary international law cannot depend on the advancement of instrumental goals some times in contradiction with the requirements of a stable legal system. The articles examines in particular the meaning of States' practice and opinio juris, the traditional elements for the formation of customary rules. It argues in conclusion that the efforts at reengineering customary law have actually revived its role to an unexpected extent, to the point that the reaction against its manipulation is gradually bringing back international law to its normal balance.

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CUSTOMIZING YOUR OWN NEEDS

Among the many incisive remarks made by Sir Robert Jennings, there is one that stands up for its accuracy and reflection of current realities: "[m]ost of what we perversely persist in calling customary law is not only not customary law; it does not even faintly resemble a customary law" (1). Yet, every passing day more and more purported rules are labelled customary law if this helps to support an argument that cannot otherwise be sustained under the law. What is most disquieting about this phenomenon is not that authors and governments tend to rely on such an approach, but that judges and practitioners have embarked in such an exercise too, prompting doubts about the very basis of international law.

Bad as this situation tends to be with respect to general issues of international law, it turns only worse in certain fields where idealism, and occasionally political interest, needs to find a rule of law even where there is none, of reach an interpretation of a rule that does not even remotely allow for such a development. A desired outcome is then substituted for the strict rule of law.

Fidler has put together an impressive account of authors who have warned about, or explained, this trend (2). With respect to human rights, Simma and Alston, for-example, have noted an "identity crisis in customary law'" because of the search for customary law wherever is needed (3); Henkin has remarked that most of human rights law cannot be identified with customary law since it does not derive from State practice or consent (4); and Sohn has also explained that States not even make the law on human rights as it emerges from people, scholars and law journals (5). The situation is not very different in connection with international environmental law (6) or, more recently, as a tool for justifying the use of force in international affairs (7).

Why is this process gaining ground and how should the traditional requirements of customary international law be strengthened in order to ensure that proper law is made, ate the main concerns that will be discussed in this contribution.

A first aspect that must be noted is that which an author has described as the "evaporation of law from international law" (8). The concerns relating to the exaggerated use of "soft law", package dealing, bargaining, settlement-type outcomes and other that author identifies, ate not alien to this particular development (9). Customary international law could not escape from a frame where regimes matter more than the law, international relations side-up with advocacy and at the very end what matters is to accomplish instrumental goals rather than count on a stable legal framework (10).

The politics underlying the different approaches to the sources of international law have also been well explained by Koskenniemi (11). The increasing criticism of consensualism to justify the departure from State consent to ascertain the existence of a rule, explained by some concept of social necessity of by the resort to some form of tacit or presumed consent, even if wholly artificial, means that non-consensualism becomes the desired outcome (12). Again, customary law cannot escape from a setting where consent and State practice are not considered relevant for the determination of the legal norm, particularly when the identification of a rule of customary law is always surrounded by some degree of difficulty.

A NOT SO MYSTERIOUS MYSTERY

It is quite true that customary international law is surrounded by mystery (13). It has even been remarked that the drafters of the Statute of the International Court of Justice and its predecessor did not have a clear idea about what custom was (14).

One such mystery is, of course, how can a rule of law develop on more than one occasion from the violation of a pre-existing rule of law (15). In tuna, the perception of what is the law on that particular matter might not be entirely shared. Indeed, the enactment of a 200-mile area of maritime jurisdiction, for example, was perceived by some as a violation of a rule on a restricted territorial sea and contiguous zone, but not by others who believed that resource-related jurisdiction was previously unknown under international law and hence there was no specific rule governing the matter in a way not dissimilar to what had happened with respect to continental shelf jurisdiction (16). The end result, however, is that one way of the other the new rule became accepted and proclaimed as customary international law, thus superseding whatever there was of there was not earlier.

MICROWAVING CUSTOMARY LAW

A second area of mystery surrounding customary law is that concerning the basis of its binding character. Barberis has rightly pointed out that the traditional explanation of the Grundnorm as the ultimate source of such binding obligation is in itself a contradiction (17). Indeed, to justify the binding nature of custom on the existence of another customary rule that so says is a rather circular argument. Yet, the very foundation of international law in Kelsen's theory of law is related to the ultimate existence of pacta sunt servanda as a rule of customary law (18).

The various theories that have been advanced to explain the nature of customary law reflect mostly a self-interested doctrinal approach that purports to justify a given view of the process, rather than to seek a real scientific answer to this difficult subject. The theory of pactum tacitum, while reflecting the need for State consent to be bound by a rule of customary law, takes this safeguard of sovereignty to the length that there would be no binding rule if such consent is not established directly or indirectly (19); it will seen that this is not actually the reality of customary law because that binding effect is in some aspects independent from the process of consent and admits exceptions thereto, albeit limited and legally precise.

Still less convincing is Ago's theory of customary law as "spontaneous law" (20), and hence different from the elaborate nature of treaty law, as it has been rightly pointed out that customary law is far from spontaneous and relies on a careful calculation by States through the process (21). Neither does Bin Cheng's view of an "instant" customary law help to explain the nature of custom, but does of course have a connection with the discussion about the interrelationship between treaties and custom that will be examined below (22).

Consensus has been another favoured theory (Suy, en Bern. P. 208, n. 6) (23), but this approach neither reflects the reality of how customary law is formed and applied. Seldom does customary law need consensus to come into being, although consensus might be achieved at a later point in the process, particularly in the context of a codification conference.

The role of natural law in explaining customary law does not lack interest (24), but this relates either to historical elements influencing the formation of the international legal system or to the identification of roles that are fundamental for the international community, as opposed to ordinary rules. This in turn is the basis for the distinction between rules of constitutional international law and other rules that do not have such importance (25). The significance of international constitutional law is gaining in importance as the global society evolves into a more structured community, and many such fundamental principles may be indeed embodied in customary law (26).

In this respect is should be noted that the International Court of Justice has not followed a consistent approach in dealing with customary law. During the period of the Permanent Court of International Justice and the early years of the present Court, consent or acceptance played an important role regarding the identification of customary rules. Thus, in the Lotus case emphasis was placed on the free will of States expressing principles of law though generally accepted conventions of usages (27). In Asylum there was a question of lack of proof of a given practice having been accepted (28), while in Fisheries the absence of protest was also influential in the outcome (29). Acceptance also appears to have inspired the Right of Passage (30) and general opinion appears to underlie Wimbledon (31).

In more recent times, however, it would seem that far from adhering to a given theory the Court has found a customary rule whenever and wherever it has deemed it necessary or convenient to identify such a rule or to go beyond treaty rules. It has been noted that in Nottebohm (32) and Barcelona Traction general rules seemed to have been enough, independently from acceptance (33). More generally, opinio juris has been at the heart of many decisions, including the North Sea Continental Shelf the Libya- Malta, and Nicaragua (34), not understood as an indication of consent but in a rather loose manner that heavily departs from the practice of States. This...