TheEuropeanJournaloflnternationalLawVol. 21 no. 1 © EJ1L 2010; all rights reserved Customary International Law in the 21st Century: Old Challenges and New Debates Roozbeh (Rudy) B. Baker* Abstract This article will survey the new non-traditional scholarship which has emerged in international law to challenge the two long-established sources of customary norms, state practice and opinio juris. With the recent growth, in the international system, of self-contained international criminal tribunals, new challenges facing international law have emerged. Institutionally structuredas self-contained legal regimes, international legal tribunals such as the ICTY, ICTR, and now the ICC have nevertheless contributed to a new paradigm within international law. The jurisprudence of these international criminal tribunals, on a wide range of international legal questions, has slowly begun to be elevated into norms of customary international law. Given this fact then, the debate over whether consistent state practice and opinio juris are the only building blocks of customary international law is over, because clearly, for better or for worse, they no longer are. The new question, the new debate, will be over what the implications of this shift in the traditional building blocks of customary international law are, not only on the international system as a whole, but also, surprisingly perhaps, on national (domestic nation state) legal systems as well. The domestic law angle is key, for in the past few years the jurisprudence of these international tribunals has, aside from finding its way into customary international law, also begun to seep into the domestic (mainly criminal) law of several countries. 1 Introduction For better or for worse, the two long-established sources of customary international law have been profoundly challenged in the past few decades. These two elements, the * Adjunct Professor of Law, Pepperdine University, Malibu, Cal. BA, University of California at San Diego; JD, University of Illinois; LLM, University of California at Berkeley; PhD Candidate (Politics and International Relations), University of Southern California. Email: Rudy.Baker@yahoo.com. E/IL(2010), Vol. 21 No. 1, 173-204 doi; 10.1093/ejil/chq01S 174 E/IL 21 (2010), 173-204 consistent practice of states,1 coupled with the determination (by the practising state) that such practice is being undertaken out of a sense of legal obligation (labelled opinio juris),2 are no longer held in the high regard they once were. Indeed, since the 19 70s, a wide range of newer non-traditional scholarship3 has emerged arguing against a strict adherence to state practice and opinio juris in determining customary international law and advocating instead a more relaxed interpretive approach.4 Within this vein, other scholars have gone further, arguing that widely ratified multilateral conventions or treaties which have established human rights prohibitions against genocide,5 torture,6 and slavery7 actually form confirmation of customary international law binding upon all states, not just the signatories.8 Pushing back against this new movement, more traditional-minded scholars have castigated its seeming attempt to create shortcuts to the generation of international norms.9 According to one of the more prominent authors of this push-back, Professor Prosper Weil of the University of Paris, the purpose of international law throughout the centuries has never been to better mankind, but rather has been to ensure a set of universally recognized and agreed upon rules which allow mankind to live in relative peace and order.10 Given this, the international legal system is always looking to ensure that its power and function are universally accepted and applicable, rather than hierarchical.11 Such a system is, argues Weil, by necessity all that international law can ever hope to achieve whilst still maintaining universal acceptability. In Weil's view, by now seeking to create a pre-eminence or hierarchy of obligations based on their content rather than on how they are created (the process), the non-traditional scholarship and its adherents are exhibiting a complete lack of understanding for what international law is.12 1 Y. Simbeye, Immunity and International Criminal Law (2004), at 3 7-38. 2 P. Malanczuk (ed.), Akehurst's Modern Introduction to International Law (1997), at 44. 5 Throughout this article the term 'non-traditional scholarship' shall be employed to describe the turn towards reinterpreting the traditional sources of customary international law. Other terms which have employed by other commentators include 'new customary international law', 'new custom', and 'modern custom'. These terms of course refer to the end result of the scholarship, whereas the term employed by this article refers to the process (scholarship) through which the end result came about. * See, e.g., Tomuschat, 'International Law: Ensuring the Survival of Mankind on the Eve of a New Century', 281 Recueil des Cours (1999) 9, at 86. ' See Convention on the Prevention and Punishment of the Crime of Genocide, 9 Dec. 1948, 78 UNTS 277. 5 See International Covenant on Civil and Political Rights (ICCPR), 19 Dec. 1966,999 UNTS 171, Art. 2; United Nations Convention Against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment, 9 Dec. 1975,1465 UNTS 85. 7 See ICCPR, supra note 6, Art. 8. 8 See, e.g., Sohn, 'The International Law of Human Rights: A Reply to Recent Criticisms', 9 Hofstra L Rev (1981) 347: Sohn, 'The New International Law: Protection of the Rights of Individuals rather than States', 32 Am ULRev(1982) 1: D'Amato, 'The Concept of Human Rights in International Law', 82 Columbia L Rev (1982) 1110: Sohn, '"Generally Accepted" International Rules', 61 Washington L Rev (1986) 1073. 9 See, e.g., Weil, 'Towards Relative Normativity in International Law?', 77 AJIL (1983) 413. 10 Ibid., at 418. » Ibid. 12 Ibid., at 42 5^2 6. Customary International Law in the 21st Century: Old Challenges and New Debates 175 With the new emergence of self-contained ad hoc13 and permanent14 international criminal tribunals this debate has become, by and large, irrelevant. Established by international treaties and institutionally designed as self-contained legal regimes, international criminal legal tribunals such as the ICTY, ICTR, and now the ICC have, nevertheless, contributed to a new paradigm within customary international law. The jurisprudence of these international criminal tribunals, on a wide range of international legal questions, has slowly begun to be elevated into norms of customary international law. Given this fact, then, the debate over whether consistent state practice and opinio juris are the only building blocks of customary international law is over, because clearly, for better or for worse, they no longer are. The new question, the new debate, will be over what the implications of this shift in the traditional building blocks of customary international law are, not only on the international system as a whole,15 but also, surprisingly perhaps, on national (domestic nation state) legal systems as well. The domestic law angle is key, for in the past few years, the jurisprudence of these international tribunals has, aside from finding its way into customary international law, also begun to seep into the domestic (mainly criminal) law of several countries. Section 2 of this article will provide a brief introduction to international law and the role treaty and custom have traditionally played in its formation. Section 3 shall recapitulate the old debate over the traditional sources of customary international law, state practice and opinio juris, analysing the newer non-traditional scholarship, first emergent in the 19 70s, which has successfully challenged these two touchstones. Section 4 of this article will chart how the jurisprudence of the ICTY and ICTR,16 on certain key questions of international law, has begun to be elevated and accepted as norms of customary international law (and how certain elements of this jurisprudence clash with long held international norms); which will then set the stage for section 5, which shall explore how this same jurisprudence has begun to seep into the national criminal legal systems of Belgium and Kosovo. Relying on new theories within sociology and international relations which describe how the relationship between global and domestic norms are an iterative process, with law making and implementation functioning in a recursive cycle between the two levels, section 5 shall describe in detail how this process has led to problematic results in Belgium and Kosovo, as the newly imported international tribunal jurisprudence has clashed with long held domestic criminal law norms 3 I.e., the International Criminal Tribunal for the former Yugoslavia or ICTY, and the International Criminal Tribunal for the Rwanda or ICTR. 4 I.e., the International Criminal Court or ICC. 5 Some have already begun, in a preliminary manner, to address this question by worrying how the international system will cope with a proliferation of international tribunals issuing possibly contradictory opinions: see Spelliscy, 'The Proliferation of International Tribunals: A Chink in the Armor', 40 Columbia JTmnsnaflL (2001) 143. 6 This article's analysis of the jurisprudence of international tribunals and their adoption into customary international and domestic law will concern itself with the work of the ad hoc ICTY and ICTR, not the permanent ICC, as the ICC has yet to adjudicate on any of its pending cases (and hence has not built a corpus of case law). 176 E/IL 21 (2010), 173-204 in those two countries. This article will conclude with its own modest normative suggestions on the way forward for international law, given the new paradigm presented. 2 The Foundations of International Law (Custom and Treaty) Before one can delve into any meaningful discussion of the old debate within legal circles of the traditional sources of customary international law and their continued primacy in the formation of international norms, a brief review of the foundations of international law is in order. International law traditionally has had two components - law deriving from custom (customary international law) and law deriving from international treaties or conventions (conventional international law). The make-up and sources of these two components of international law will be discussed in turn. A Customary International Law Customary international law, it is generally agreed, finds its source in the widespread consistent practice of states.17 International custom is seen as a source of international law because the thought is that if states act in a certain consistent manner, then such states may be acting in such a manner because they have a sense of legal obligation -dubbed opinio juris. If enough states act in such consistent manner, out of a sense of legal obligation, for a long enough period of time, a new rule of international law is created.18 The system can thus be thought of as circular, in that states are in effect creating a rule, through acting in conformity with such rule over a period of time, because they feel they are legally obligated to do so.19 Customary international law depends upon the consent of nation states, which can be either explicit or implicit.20 Thus, if in theory a nation state does not wish to be bound by a new rule of customary international law, then it can, in theory, vocally object and announce that it does not view itself as bound.21 This objection must be consistently reiterated, lest it be lost.22 Two (or more) states could also then enter into an agreement or treaty, between one another, and in such treaty contract out of one or indeed a whole set of customary 7 T. Buergenthal and S.D. Murphy, Public International Law (3rd edn, 2002), at sect. 2-4. 8 Note that there can also exist regional customary law which is binding on a group of nation states in a particular region, but not upon the international system as a whole: see Asylum (Columbia v. Peru) [1950] ICJ Rep 266. 9 What of the situation, however, when one has an inconsistency between state practice and opinio juris (on the part of one or a group of states)? According to the International Court of Justice, in such situations state conduct which runs counter to the rule should be viewed as a violation of such rule, not as evidence that the state does not intend to recognize it: see Military and Paramilitary Activities (Nicaragua v. US) [1986] ICJ Rep 14, at 98. 10 I.e., if a rule of customary international law is emerging and a nation state remains silent, then this can be seen as giving implicit consent that the nation state will be bound by the new customary rule: see Restatement (Third) of the Foreign Relations Law of the United States (198 7), at sect. 102 comment d. 11 See Fisheries Case (UK v. Norway) [1951] ICJ Rep 116. But see also supra note 19. 12 See Arnett, 'Death at an Early Age: International Law Arguments Against the Death Penalty for Juveniles', 57 UCincinnatiL Rev (1988) 245, at 260 n. 113. Customary International Law in the 21st Century: Old Challenges and New Debates 177 international rules. New nations, however, it is generally held, cannot choose between the various rules of customary international law23 - they are bound by all of the accepted customary rules (at the point of independence).24 It does not matter that, of course, such newly independent states were unable to object to rules of customary international law as they were being formed. The above being said, however, it is important to note that there are certain rules of customary international law which are considered so vital that they cannot be contracted out of by individual states - such preemptory rules are dubbed jus cogens norms.25 Opinio juris plays a key role in elevating a regular customary international law norm into a jus cogens norm, for only when the majority of states in the international system believe that such a norm cannot be persistently objected to, or contracted out of, does a regular customary norm achieve elevation to a jus cogens norm.26 Running parallel to jus cogens norms are what are called obligations erga omnes. Obligations erga omnes are obligations considered so vital and important within the international system (usually in the form of jus cogens norms) that any state (whether directly affected or not) may sue another state in order to compel the obligation to be met.27 In this way obligations erga omnes can be seen as a determinant in questions concerning jurisdiction and standing in international law.28 B Conventional International Law Conventional international law finds its source in 'international conventions, whether general or particular, establishing rules expressly recognized by the contesting states'.29 Bilateral treaties are seen as creating obligations specific to the two states which signed them. Usually, such conventions or treaties, if entered into between only two states, are of course binding on the two states in question, but are not generally a source of international law. Multilateral treaties, on the other hand, can transform into sources of customary international law, binding on all states in the international system, whether they are parties to the particular treaty or not, if a large enough portion of non-signatory states in the international system adheres to their provisions out of a sense of legal obligation, i.e., opinio juris.30 23 For the minority-held contra view see Virally, 'The Sources of International Law', in M. Sorensen (ed.), Manual ojPublic International Law (1968), atll6,148. 24 Restatement, supra note 20, at sect. 102 comment d. 25 Vienna Convention on the Law of Treaties, 23 May 1969,155 LINTS 331, Arts 53, 64, 71;D.J.Bederman, International Law Frameworks (2001), at 23. 26 R. Higgins, Problems and Processes: International Law and How We Use It (1995), at 22. Other commentators, however, depart from this vision of jus cogens as a clear-cut concept: see, e.g., Parker and Neylon, 'Jus Cogens: Compelling the Law of Human Rights', 12 Hastings lnt'l & Comp L Rev (1989) 411, at 414-416 (where the authors demonstrate the difficulty in determining the meaning of jus cogens through a discussion of the variety of definitions it has been given). 27 Barcelona Traction, Light & Power Co., Ltd. (New Application) (Belgium v. Spain) [1970] ICJ Rep 4, at 33-34; Bederman, supra note 2 5, at 2 3. 28 Simbeye, supra note 1, at 59-60. 29 Statute of the International Court of Justice, 26 June 1945,156 LINTS 77, Art. 38(l)(a). 50 Buergenthal and Murphy, supra note 17, at sect. 2-4. 178 E/IL 21 (2010), 173-204 3 The Old Debate: The Sources of Customary International Law While state practice and opinio juris were, as has been seen, long held as the accepted sources of customary international law, the past few decades have seen a concerted movement in legal scholarship which has sought to redefine the sources of customary international law away from a blanket reliance on these two sources. At its most extreme, this scholarship argues that international treaties, especially those encompassing human rights obligations, actually generate international legal norms,31 because such conventions are inevitably not simply the codification of existing legal norms but rather the creation of new ones.32 Relying, at times, on findings from the International Court of Justice,33 a framework has been presented by this scholarship which seeks to modify the role of prolonged state practice and opinio juris in the process of transforming conventional or treaty-based international law (binding only on the state signatories) into customary international law (binding on all).34 This non-traditional scholarship presents a framework which insists that the signing of a convention or treaty by a wide group of countries is, in and of itself, evidence of the creation of new customary legal norms. Although this non-traditional scholarship has ultimately been successful in redefining the sources of customary international law, such a move has not been without its critics. A Developments within the International Court of Justice In the late 1960s and early 19 70s the International Court of Justice (ICJ) was, in a set of novel, even revolutionary, opinions, setting up the doctrinal basis for a re-think of the traditional sources of customary international law: state practice and opinio juris. In the Barcelona Traction35 decision, the ICJ, in adjudicating on a claim by Belgium on behalf of certain of its nationals who were shareholders in Barcelona Traction Ltd. (a trading company incorporated in Canada) against alleged actions of the Spanish state which Belgium claimed were contrary to the principles of international law, greatly expanded the standing requirement under international law for states to claim violations. Normally, for a state to have standing to claim a violation of international law it must be directly affected by the violation at issue. However, as has been discussed, certain violations of customary international law are considered so vital that the system will allow any state to claim violation, and not simply the state directly J1 See, e.g., D'Amato, supra note 8, at 1129. J2 Ibid., at 1137-1138. J3 Sitting in The Hague, the ICJ is the principle judicial organ of the UN. All members of the UN are ipso facto members of the Court, and must therefore adhere to the Court's Statute. The Court consists of 15 judges, elected by absolute majorities in both the UN General Assembly and Security Council. M See, e.g., North Sea Continental Shelf, (W Germany v. Denmark, W Germany v. Netherlands) [1969] ICJ Rep 3 (where the ICJ had held that 'widespread and representative' adoption of a conventional/treaty rule by non-signatory states, coupled with only the passage of a 'short period' of time, was all that was required to transform conventional international law into customary international law). 55 Barcelona Traction, Light & Power Co., Ltd. (New Application) (Belgium v. Spain), supra note 2 7. Customary International Law in the 21st Century: Old Challenges and New Debates 179 affected - obligations erga omnes.36 In Barcelona Traction, the Court held that the 'basic rights of human persons' created erga omnes obligations.37 Thus, in the eyes on the Court, the protection of human rights did have a place in the international legal system. In the North Sea Continental Shelf8 decision, the ICJ rejected claims by both Denmark and the Netherlands that West Germany was bound by Article 6 of the 1958 Geneva Convention on the Continental Shelf39 (and the principle of equidistance contained therein) in delineating the boundaries of its continental shelf vis-a-vis Denmark and Norway. West Germany was not a signatory to the Convention, and thereby not formally bound by its provisions, but Denmark and the Netherlands argued that the provisions of the Convention had transformed into customary international law (and were thereby binding on West Germany), and that West Germany itself had shown predilection to be bound by the rules contained in Article 6. The Court rejected this argument, and held that predilection was not enough; rather that there had to be some showing of opinio juris to demonstrate that the behaviour in question had transformed the conventional norm into a customary one.40 Up to this point, the Court's opinion had been fairly conservative and in line with traditional conceptions of international law. The revolutionary doctrine came in when the Court pronounced its view on (1) the amount of widespread participation required for a conventional rule of international law, binding only upon those states that have signed the convention at issue, to transfer into a customary rule of international law, binding on all; and (2) the amount of time required for this transformation to take hold. With regard to the first question, the Court stated that only a 'widespread and representative participation in the convention might suffice of itself to transform the purely conventional rule into a customary one.41 With regard to the second question, the Court found that it could be that 'the passage of only a short period of time is not necessarily, or of itself, a bar to the formation of a new rule of customary international law on the basis of what was originally a purely conventional rule'.42 Thus, to summarize the Court's position: while opinio juris would be required to transform a conventional norm into a customary one, this requirement would not be required of all the states in the international system, or even a majority; rather only 'widespread and representative' participation would be required; and only the passage of a 'short period' of time would suffice to seal the transformation (from conventional to customary international law). Thus, in the eyes of the Court a treaty provision adopted by a sufficiently representative sample of states could undergo a near instantaneous transformation into a norm of customary international law.43 56 Bederman, supra note 2 5, at 2 3. 57 Barcelona Traction, supra note 27, at 32. 58 North Sea Continental Shelf, supra note 34. 59 Convention on the Continental Shelf, 29 Apr. 1958, 499 ÜNTS 311, Art. 6. 10 North Sea Continental Shelf, supra note 34, at 41. « Ibid., at 42. 12 IK