This article asks whether genocide follows the age and gender distributions common to other crime. We develop and test a life‐course model of genocide participation to address this question using a new dataset of 1,068,192 cases tried in Rwanda's gacaca courts. Three types of prosecutions are considered: 1) inciting, organizing, or supervising violence; 2) killings and other physical assaults; and 3) offenses against property. By relying on systematic graphic comparisons, we find that the peak age of those tried in the gacaca courts was 34 years at the time of the genocide, which is older than the peak age for most other types of crime. We likewise find that women were more likely to participate in crimes against property and comparatively unlikely to commit genocidal murder. Symbolic–interactionist explanations of crime suggest people desist from crime as a result of shared understandings of the expectations of adulthood. We argue that this process may be turned on its head during genocide as participants may believe they are defending their communities against a perceived threat. Thus, in contrast to other criminological theories suggesting that people must desist from crime to be accorded adult status, some adults may participate in genocide to fulfill their duties as adult men.