Harvard Professor Beth Simmons and Hyeran Jo have been praised in oGR and by Kenneth Roth, executive director of Human Rights Watch, for research claiming that the International Criminal Court (ICC) deters atrocities in member states. If true, this would be good news at a time when many prominent justice practitioners have retreated from such claims. Even former Yugoslavia Tribunal prosecutor Louise Arbour is now warning that “criminal prosecutions can complicate if not impede peace processes.”
Upon closer inspection, Jo and Simmons’ claims appear to be based on shaky methods. The ICC’s deterrent effect, if any, is far smaller than they suggest in their working paper and in high-profile briefings to prominent activists.
Jo and Simmons argue that a state’s ratification of the ICC’s Rome treaty reduces, on average by 60%, the number of its intentional killings of civilians in military confrontations. They analyze conflicts that took place between 1989 and 2011 to see whether there has been a marked change since 1999 when the Rome Statute was negotiated and states began to ratify this treaty. They also claim that when joining the ICC is associated with domestic legal changes to conform to ICC rules, killings also decline by 60%, and that social pressure in ICC ratifiers, measured by the presence of rights organizations, also reduces killings. Atrocities by rebel groups are not affected by ICC ratification or domestic legal changes. But Jo and Simmons claim that “ICC actions”—which they measure globally rather than by country—impress rebels enough to reduce their intentional civilian killings by 30%.
