This study explores the local effects of internal armed conflict on postwar violent crime in Northern Ireland. It argues that exposure to wartime violence will lead to higher levels of violent crime in the aftermath of conflict. Particularly, it claims that exposure to violence committed by armed groups challenging the state (anti-government groups) will have this effect, as it erodes the legitimacy needed for local law enforcement agencies to function effectively. This, in turn, is expected to contribute to the emergence of a postwar public security gap that lowers opportunity costs to resort to violent crime for a range of local actors. To evaluate these propositions, spatial statistics on a subnational dataset covering war-related fatalities for the period 1969–98 and police crime records for the postwar period 2002–06 are employed. The results indicate that the more an area has been exposed to violence, and the larger the proportion of this violence committed by anti-government groups, the more violent crime on the local level. This study hence contributes both to the burgeoning literature on the legacies of civil war and to recent research emphasizing the need to disaggregate non-state actors.