International criminal tribunals have developed a number of legal theories designed to hold individuals responsible for their role in collective criminal conduct. These doctrines of criminal participation, known as modes of liability, are the subject of significant scholarly commentary. Yet missing from much of this debate, particularly as regards the International Criminal Court, has been an analysis of how current doctrine on modes of liability responds to the need to hold collective perpetrators criminally responsible for crimes of sexual and gender-based violence (SGBV). Indeed, many writings in this area of the law address perceived shortcomings in the theoretical underpinnings of modes of liability doctrine in the abstract but ignore the application of this doctrine in concreto. As a result, facially neutral writings on modes of liability may in fact be gendered in application, either because they fail to account for the specific characteristics of sexual and gender-based violence or because they are applied in a manner that requires higher thresholds for finding culpability for the commission of SGBV crimes. This article fills the gap between theory and practice, examining past and present doctrine, and suggesting ways in which the treatment of modes of liability by international criminal courts and tribunals can both properly respond to the need for personal culpability and the dangers of collective criminal activity, particularly as regards SGBV crimes.

On 7 March 2014, Trial Chamber II of the International Criminal Court (ICC) convicted Germain Katanga for war crimes and crimes against humanity. Katanga's conviction is based on the concept of common purpose liability as regulated in Article 25(3)(d) of the Rome Statute. This liability theory establishes criminal responsibility for wilfully or knowingly contributing to the crimes of a group of persons who act together pursuant to a common purpose. The ICC regards common purpose liability as a residual liability theory, which provides for a lower level of blameworthiness than principal forms of criminal responsibility, such as joint perpetration. This article appraises the residual and inferior status of common purpose liability by comparing the ICC's application of common purpose liability and joint perpetration. The comparison makes clear that common purpose liability in theory stipulates lower actus reus and mens rea standards than joint perpetration. However, in practice the ICC applies the requirements of both these liability theories in a context-dependent way in interplay with the particular facts of individual cases. It can therefore not be concluded in general terms that common purpose liability by definition constitutes a less serious type of criminal responsibility than joint perpetration. Instead, it is preferable to adopt a flexible approach, which recognizes that common purpose liability covers a variety of conduct entailing different levels of blameworthiness.