Internationalizing Non Bis In Idem: Towards a unified concept of double jeopardy in the application of universal jurisdiction over international core crimes.

By Dr. Hilly Moodrick-Even Khen*

During the last decades, international criminal law has been developing through the unification of states around concepts of universal justice, mainly in order to frustrate international core crimes and to deter their perpetrators. The main manifestations of this project were the proliferation of the concept of universal jurisdiction over international core crimes and the establishment of the ICC which succeeded in unifying a notable number of states around the denouncement of international core crimes and the endeavor to prevent their commission. The ICC also succeeded in forming a system of hierarchy between the Court's jurisdiction and other competing jurisdictions through the application of the principles of complementarity and non bis in idem (also known as double jeopardy principle).1

However, the unification of states around what can be described as international criminal norms or international criminal justice is opposed to state sovereignty which is expressed in the criminal system as the supreme power vested in a state to prescribe law and bring to justice anyone who defies the autonomous law-giving power of the sovereign; one of the major expressions of this tension is the application of the double jeopardy principle in inter-state cases. Indeed, and in contradiction to the central place of this principle in international criminal law, some states deny it (on the international level) and claim their own sovereign interest in criminalizing and bringing to justice a suspect.2

In this short article, I raise several suggestions for mitigating the international interest in the application of international criminal norms with the interest of states to preserve their sovereignty and with the interest of criminal law to sustain the defendant's right for due process. While acknowledging both the significance of the international interest in repressing and prosecuting international core crimes and the importance of the cooperation of states for achieving this goal, I propose guidelines for a unified concept of double jeopardy. I, yet, secure its legitimacy by anchoring the guidelines in states' practice in the application of the principle of non bis in idem.

Double Jeopardy and Complementarity within and outside the ICC System

The establishment of the permanent International Criminal Court (ICC) introduced some standards of hierarchy between competing jurisdictions by using the governing principle of complementarity,3 according to which a state that has jurisdiction over a certain case should be given a first chance to complete a fair and effective investigation. However, although the principle of complementarity as provided for in the Rome Statute does serve as an important guideline on decisions with regard to competing jurisdictions, several issues are left unresolved. First, although this principle governs the competition between national jurisdictions and the ICC, it does not necessarily resolve the competition between different national jurisdictions outside the ICC system. In addition, the complementarity principle in the ICC Statute is itself constituted by very general concepts: one issue that still remains ambiguous, for example, is what precisely qualifies as ability or willingness by states to investigate criminal cases that lead to the ICC waiving its right to interfere. These elements and others have been interpreted by scholars and commentators of the ICC Statute;4 however, national systems do not necessarily abide by these definitions in their application of the principle. As a result, there is no common practice on complementarity at the national level.

In the ICC Statute, complementarity is intertwined with the non bis in idem principle; however, the latter principle is itself a fraught concept in criminal law. Questions related to its application allow for a number of possible interpretations: Should the principle of double jeopardy relate to a conduct or an offense? How should grounds for excluding criminal liability be taken into account with regard to the existence of double jeopardy? And how should the outcome of the criminal procedure — acquittal or conviction — be evaluated?

The above questions demonstrate the need for a universal application of the principles of double jeopardy which should be nevertheless based on states practice; i.e., dicta and legislation. The internationalization of national law will create a common system for employing universal jurisdiction and will clarify the priority scale for states willing to apply such jurisdiction over international core crimes. The contours for this priority scale should take into consideration factors that influence the effectiveness and fairness of the investigation and prosecution of suspected perpetrators of core crimes. To take an example, a major consideration is which state has the most access to information and means of performing such an investigation. Another important consideration is which state has a rule- of- law- based jurisdiction that would most adequately provide the defendant with due process machinery. Hence, the creation of such a universal system will provide the most capable states with incentives to repress international core crimes while the jurisdiction of other states will be subsidiary and could be enforced only if the former states fail to act. As a result, the interest of preventing impunity from those who are suspected of committing international core crimes will be better secured.

A Brief History of States' Practice of Universal Jurisdiction

The international community’s interest in frustrating international core crimes through universal jurisdiction has been channeled through two parallel routes. In the first, and especially in recent years,5 several states have legislated laws that apply universal jurisdictions over international core crimes. For example, Spain legislated the Organic Judiciary Act in 1985, Belgium legislated the law on the Suppression of Serious Violations of International Humanitarian Law in 1993, and Germany legislated the National Code of Crimes against International Law (VStGB) in 2002.6 This is in addition to the numerous states that apply universal jurisdiction due to their obligations in international treaties, such as the Geneva Conventions (1949), or the Convention against Torture (1984).

States that apply universal jurisdiction face the issue of competing jurisdictions, and they have to take into consideration questions of complementarity or superiority of their own jurisdiction. It is quite recently, for example, that the criminal chamber of the Spanish National High Court gave a decision on whether the Shehadeh case7 can be litigated before Spanish courts; in this case, the Court had to consider whether Israel's competing jurisdiction over the case would supersede its own. In its ruling, the Court dealt with questions of complementarity: that is, it had to decide whether Israel was performing an investigation in good faith and whether it was capable of completing the investigation. By contrast, in the Guatemala Case, the Spanish Supreme Court accepted a broad version of universal jurisdiction that was limited only by res judicata and hence did not accept any other jurisdiction as superior to its own.

The second manifestation of the international interest in repressing international core crimes was the establishment of the international criminal tribunals, with the ICC creating its own concept of complementarity. The elements of this concept are fixed within the ICC Statute and interpreted through the rulings of the ICC.8 Scholars have added their own elucidations,9 thus working towards the formation of an international legal concept of the principle of complementarity.

A similar division between national and international jurisdictions can be traced with regard to non bis in idem. This principle is a cornerstone of many national criminal jurisdictions.10 Its underlying rationale lies in securing the individual's right11 to a due process of law in which once the criminal process dealing with a specific offense or conduct is concluded, justice has been exhausted and the accused should not be re-tried.

In terms of international criminal law, non bis in idem seems to serve as a fundamental principle of international criminal jurisdiction, one that can be extrapolated from the statutes of all international criminal tribunals and the ICC. However, although the ICC applies the principle of complementarity in the context of the application of double jeopardy, the ICTY and the ICTR refer to the concept of primacy, under which the non bis in idem principle is limited by [the] “impartial…, independent…, and diligent” prosecution of the competing state and by the demand that the suspect not be prosecuted for committing an ordinary crime.12

Finally, and like the principle of complementarity, international tribunals’ definitions of the double jeopardy principle are not binding in domestic criminal systems, and each state is free to interpret the constituents of this principle on its own.13 These conflicting interpretations could result in cases where the right of the accused to avoid double jeopardy is not adequately safeguarded.

Towards a Unifying System- Some Questions that Should Be Given Thought

Although the non bis in idem principle has a long tradition of application, its core constituents are not uniformly interpreted. This lack of uniformity raises several questions that need to be answered to substantiate non bis in idem as a core principle of international and national criminal law. For example, should the prohibition on double criminality refer to the same conduct or to the same offense? What are the implications of the choice between a similar conduct and a similar offense when an offence is purposely defined in a certain manner in order to shield the suspect? What are the implications of defining a crime as “ordinary” or as international when it comes to the application of the double criminality principle?

Similar questions should be asked (and answered) with regard to the relatively new principle of complementarity; their answer may serve as a basis for interpreting the double jeopardy principle. How should the foundations of the principle of complementarity laid down by the ICC Statute be adapted to the legislation of national jurisdictions? For example, how should the demand for conducting an investigation in good faith be interpreted? What should the governing principles of a good faith investigation be? Should strict rules of investigation be adapted (as suggested by EctHR dicta)?14 How should general arguments against the credibility of a state's legal system be addressed?


The prevention of international core crimes and the punishment and deterrence of their perpetrators are not purely legal matters, but have great societal importance. It is in the interest of every local society and of the international community to redress crimes of genocide, war crimes, and crimes against humanity. It is also in the interest of national jurisdictions and the international community to facilitate cooperation between states to achieve this goal.

One of the major concerns of the international community regarding international core crimes is the need to eliminate impunity for perpetrators of such crimes. In order to achieve this goal, states should cooperate in the effort of bringing about fair and efficient investigations of these crimes. This cooperation can be better attained if states operate according to common and universal legal principles of complementarity and non bis in idem. The universal application of these principles could contribute to achieving this goal because it will both induce states to perform such an investigation and ensure that such an investigation is just in the eyes of the international community.

To conclude, a universal application of the principles of complementarity and double jeopardy could bring about the unifying results described above. Therefore, research aimed at creating a system for such application would clearly be a benefit to society—on both national and international levels.

*Dr. Hilly Moodrick-Even Khen is a Senior Lecturer, Sha'arei Mishpat College, Israel



    1. I shall hereinafter use these terms alternatively.

    2. For example, the double jeopardy clause of the US Constitution’s Fifth Amendment covers only multiple prosecutions by the same sovereign; this trend is followed by some civil law states, such as Germany and Italy. Other civil law states offer some level of double jeopardy protection, but they withhold it when the alleged suspect is suspected of committing crimes on their soil.

    3. Note that although this article focuses on the principle of double jeopardy I also touch upon the principle of complementarity, which is a related (and complementary) concept.

    4. See, for example, John T. Holmes, The Principle of Complementarity, in, Introduction to The International Criminal Court: The Making of the Rome Statute 41, 73-74 (Roy S. Lee ed., 1999); O. Triffterer (ed.), A Commentary on the Rome Statute of the International Criminal Court: Observers' Notes, Article by Article (2nd edn., Oxford and Oregon: Hart Publishing, 2008); A. Cassese, P. Gaeta and J.R.W.D. Jones (eds), The Rome Statute of the International Criminal Court: A Commentary, Vol I (Oxford: Oxford University Press, 2002); Jann K. Kleffner, Complementarity in the Rome Statute and National Criminal Jurisdictions (Oxford U.P, 2008).

    5. Similar trends can be traced back to the Second World War, in which Nazi perpetrators of war crimes were tried by military commissions, tribunals, and courts of the Allied Nations. See Kleffner, ibid, at p. 34.

    6. It should be noted that the Belgian and Spanish laws have been narrowed down considerably by subsequent legislation.

    7. Appeal no. 31/09 Section 2 Case no. 118/09 National High Court, Criminal Chamber.

    8. See the Appeals Chamber decision in the Katanga Case ICC-01/04-01/07 OA 8 Situation in the Democratic Republic of the Congo, The Prosecutor v. Germain Katanga and Matuieu Njudjolo Chui (25 Sep. 2009).

    9. See supra n. 4 and accompanying text.

    10. For general literature on double jeopardy in criminal law see, for example, George C. Thomas III, Double Jeopardy, The History, The Law (New York University Press, 1988); Martin L. Friedland, Double Jeopardy (Clarendon Press, Oxford, 1969); Jay A. Sigler, Double Jeopardy The Development of a Legal and Social Policy (Cornell University Press, 1969).

    11. In some cases, even a constitutional right: see, e.g., the double jeopardy clause of the U.S Constitution's Fifth Amendment. See also supra n. 2 and accompanying text.

  1. International Criminal Tribunal for Yugoslvia (ICTY) Statute, Art. 10; International Criminal Tribunal for Rwanda (ICTR) Statute, Art. 9.

    1. Questions regarding the possible various interpretations of the constituents of the principles of complementarity and double jeopardy will be dealt with in the next section of the proposal.

    2. See, for example, McCann et al. v. the United Kingdom, 27.9.1995; Kaya v. Turkey, 19.2.1998; Finucane v. the United Kingdom, 1.7.2003; Isayeva v. Russia, 24.2.2005.