Chapter 19 The Principle of Complicity under International Law – Its Application to States and Individuals in Cases involving Genocide, Crimes against Humanity and War Crimes

Erik Kok*

1. General introduction Th is chapter introduces and applies a conceptual framework that enables a com- parison of how states and individuals engage international responsibility for their complicit conduct. Doing so will inter alia explain how in contrast to interna- tional criminal law, the relevant rules for states often constitute (primary) obliga- tions of conduct rather than (secondary) rules of attribution. Th e chapter then moves to an elaboration of how various courses of action lead individuals and states, respectively, to incur responsibility. For reasons explained there, special attention will be devoted to the situations in which a common plan to commit a wrong exists. Next this chapter argues that any diff erences regarding how the principle is applied to states and individuals, respectively, is unproblematic.

2. The concept of complicity Th e principle of complicity lacks defi nition and has rightly been described as ‘a drama of great complexity and intensity’.1 Neither the law of State responsibility nor international criminal law attaches a fi xed meaning to the word ‘complicity’. Th e term was explicitly rejected for use in the International Law Commission (‘ILC’)’s project on the codifi cation and development of general rules on state re- sponsibility, on the ground that the word invited inappropriate associations with

* Erik Kok is employed at the Amsterdam Centre for International Law and in the Defence before the ICTY. He publishes on international criminal law and is engaged in PhD research on State responsibility for dangerous and contributory conduct vis- à-vis another State’s internationally wrongful act. He can be reached at e.kok@uva. nl. Th e author is much indebted to André Nollkaemper, who provided excellent and elaborate comments on a previous draft. In addition, many thanks are due to Jean d’Aspremont, Lela Scott and the editors of the current volume. 1 Doudou Th iam Eighth Report on the Draft Code of Crimes Against the Peace and Security of Mankind, UN Doc. A/CN.4/430 and Add 1 (1990), para. 38, at 32. Van den Herik and Stahn (eds.), Th e Diversifi cation and Fragmentation of International Criminal Law © 2012 Koninklijke Brill nv. Printed in Th e Netherlands. isbn 978 9004 21459 0. pp. 557-590. 558 Erik Kok Part II

domestic criminal law.2 Th e Genocide and Torture Convention both contain a single reference to ‘complicity’ as a form of banned participation. Th e only inter- national criminal law statute to use the term is that of the ICTR, and its inclusion there is commonly explained with reference to poor drafting practices.3 Th ose from the continental tradition commonly see ‘complicity’ as a synonym for the provisions on ‘aiding and abetting’ and ‘complicity’ in international crim- inal law statutes.4 Lawyers from common law jurisdictions however routinely view the term as encompassing all rules that attribute a crime to a participant.5 In public international law, it is mostly used as a reference to Articles 16 and 41 of the Draft Articles on Responsibility of States for Internationally Wrongful Acts (‘ASR’) on ‘aid and assistance’ and assistance in serious breaches of peremp- tory norms, and the paragraphs on ‘complicity’ in the respective Conventions on Genocide and Torture.6 Th roughout this chapter we will see that the above provisions pertaining to states fi nd scarce application in practice. As is explained below, this is because states are bound to a variety of (primary) rules of conduct that serve to limit or prevent them from contributing to international crimes. A proper comparison of how states and individuals, respectively, incur responsibility for their complicit conduct must consequently take these into account. Th erefore a broad understanding of the principle of complicity is adopted. Complicity fi nds expression in rules which prohibit certain conduct because of the infl uence or potential infl uence that conduct has over the commission of a wrong. ‘Complicity’ in a wrong thus occurs when an actor violates a rule that was designed to prevent it from (negatively) infl uencing that wrong. Rules that have such a purpose are ‘complicity’ rules. Complicity as a principle defi nes and explains the circumstances under which an actor’s contribution to a wrong leads it to incur responsibility. In addition, the principle crafts the nature of the re-

2 J. Quigley, ‘Complicity in International Law: a New Direction in the Law of State Responsibility’, (1986) 57 BYIL 77, at 79. 3 E. van Sliedregt, ‘Complicity to Commit Genocide’, in P. Gaeta (ed.), Th e UN Geno- cide Convention – a Commentary (2009), 162-92, at 167. 4 Th e distinction between aiding and abetting genocide, and complicity in genocide has long been a source of controversy. Boas et al submit that ‘the chambers have almost invariably dealt with them as a single legal concept’. G. Boas et al, Forms of Responsibility in International Criminal Law (2007), 307. 5 Canadian Federal Court Judge Létourneau referred to ‘the principle, generally ac- cepted under domestic and customary international law that complicity refers to methods or means of committing a crime […]’. Canada Federal Court of Appeal, Za- zai v. Canada, 2005 FCA 303, 20 September 2005, para. 21, quoted in van Sliedregt, supra note 3, at 186. 6 Art. III (e) of the 1948 Convention on the Prevention and Punishment of the Crime of Genocide (‘Genocide Convention’), 78 UNTS 277; Art. 4(1) of the 1984 Conven- tion against Torture and Other Cruel, Inhuman or Degrading Treatment or Punish- ment (‘Torture Convention’), U.N. Doc. A/39/51 (1984).