Abstract This article analyses the increasingly pervasive enrolment of visual materials in the evolution and contestation of international criminal justice. We posit that this emerging field of ‘visual advocacy’ is transforming how international criminal law is produced and perceived. Visual advocacy stands to complement and reinforce, but also to challenge and subvert conventional norms and narratives. To probe how these dynamics play out in practice, we delve into the role of imagery in the ongoing controversy over the international criminalization of severe environmental destruction as ‘ecocide’. By articulating claims to non-human victimhood, the ecocide campaign pioneers an ecocentric vision that disrupts the anthropocentric aesthetics of international criminal law. Through a visual content analysis of 68 images posted by the movement organization Stop Ecocide International on X/Twitter and Instagram over the course of 2022, we explore how victimhood is depicted and concretized, how such imageries are framed, and how they appeal to legal authority. While our analysis underlines the critical potential of visual media as an epistemically emancipatory vehicle, it also evinces enduring ties to reductionist stereotypes and well-worn ‘aesthetic biases’.