Scholars have suggested that ratifying international treaties and implementing them within national legal systems can lead to the acceptance and (eventually) internalisation of international norms. Likewise, failing to ratify might suggest that states reject such norms. Similarly, ratifying the Rome Statute is often promoted as the primary measure to give effect to the norms protected by international criminal law. This perspective of the diffusion of international criminal justice involves at least three characteristics. First, a temporal aspect, in that states are expected to progress from rejecting international criminal justice toward acceptance over time. Second, it reveals a spatial awareness, including by distinguishing between international and 'local' norms and actors. Third, this approach includes assumptions about the movement of ideas across both time and space, or directionality. This article challenges temporal, spatial, and directional assumptions about how states engage with international criminal justice with reference to experiences in Southeast Asia. events, remain unresolved. 5 How could, or should, the perpetrators of this violence be prosecuted? Which actors are involved and what strategies do they develop to seek the prosecution of atrocity crimes? The politics of international criminal law is intertwined with questions about the spread of international norms-in particular, how states may come to accept or internalise international legal obligations. Scholars have recognised that a version of 'international criminal justice' involving the use of 'international' institutions to prosecute individuals for these types of serious violence might be considered 'normalized', 6 particularly since the establishment of the International Criminal Court (ICC). Some constructivist norm diffusion theories suggest that international criminal justice is obtained over time 7 through interaction between spatially differentiated actors and ideas, 8 which encourages the external idea to flow in the direction of receiving locals. 9 This suggests a linear path where, with the influence of civil society and other states, states progress from rejecting the Rome Statute toward inclusion within the ICC framework, represented by ratification or (at least) the adoption of domestic laws that closely replicate the international model. However, this article argues that legal responses to atrocity crimes do not only result from international norms being transmitted to receptive locals.