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 can be 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.