Shared Responsibility and Non-State Terrorist Actors

International law presently addresses the unique challenge to international peace and security posed by trans-national terrorism through two frameworks of responsibility: first, individual criminal responsibility; second, state responsibility. These two frameworks of responsibility are not mutually exclusive and this article develops an analytic framework for shared responsibility in the terrorism context. The framework reveals that (1) in most cases of potential shared responsibility, two sets of actors (states and non-state terrorist actors) contribute separately to a harmful outcome; (2) in cases where the terrorist conduct of non-state terrorist actors is not attributable to a state, the nature of the wrongful act committed is different, even if the responsibility is shared; and (3) where there is shared responsibility, the nature of responsibility which attaches to the wrongful acts of these distinct actors is itself different (criminal vs civil or delictual). This article further explores some of the difficulties in the interpretation and practical application of both the primary and secondary rules of international law which undermine the potential for shared responsibility in the terrorism context, or worse, are a recipe for no responsibility at all. It concludes with some alternative approaches to interpretation and application to address those difficulties