Holding the Line: International Law and the Fight Against Mass Atrocities

This article examines the renewed international effort to negotiate a Convention on the Prevention and Punishment of Crimes Against Humanity against the backdrop of a deteriorating rules-based international order. While genocide and war crimes are regulated by dedicated treaty regimes, crimes against humanity remain without a standalone universal convention establishing comprehensive State obligations. The article argues that this legal gap has contributed to uneven national implementation, limited accountability, and persistent impunity. Drawing on practitioner experience and contemporary conflict dynamics, it highlights how protracted wars, mass atrocities, and open challenges to multilateral justice mechanisms have intensified the urgency of normative renewal. The article analyses how a dedicated convention could strengthen domestic criminalisation, jurisdictional obligations, international cooperation, and preventive measures, while also serving a broader normative function by reasserting the political and reputational costs of disregarding international law. It further situates current negotiations within a wider ecosystem of State and civil society engagement, emphasising the role of transnational advocacy initiatives in sustaining momentum. Ultimately, the article contends that, although a convention will not end atrocities, it represents a necessary step in reinforcing international law’s capacity to shape behaviour, structure expectations, and defend civilian protection in an era of fragmentation.