ABSTRACT Important innovations have occurred and spread in international criminal law and justice. Arguing that they result from institutional learning, this essay focuses on universal jurisdiction, a principle of international law that invites the prosecution of perpetrators of core international crimes (war crimes, crimes against humanity, crimes of aggression, and genocide), irrespective of their nationality and the country of perpetration. It further addresses the increasing use of “crimes against humanity,” requiring proof of systematic or widespread patterns of offending against a civilian population; specialized investigatory and prosecutorial units; structural investigations; and the involvement of coordinating agencies working across national boundaries. Learning by criminal legal institutions is enhanced as civil society organizations, including ones growing out of refugee populations, discover and seize new legal opportunities to enhance accountability and a public understanding of mass atrocity crimes. Recent years have witnessed a growing body of literature on these trends, core contributions to which are reviewed in this essay.
LaBranche et al. (Sat,) studied this question.