This study explores the impact of civil action in two communities with different levels of violence during the 1971–1976 period in Northern Ireland’s Troubles. This chapter argues that although members of the police, military, Irish Republican Army (IRA), and loyalist paramilitaries perpetrated violence, the degree of civil action in interactions between these groups and civil rights protesters, counterprotesters, politicians, and community members impacted the trajectory and level of violence within communities. In the Dungannon district, uncivil action in the form of the police colluding with loyalist counterprotesters exacerbated local polarization and subsequent republican and loyalist radicalization. A retaliatory cycle of IRA and loyalist violence began that institutionalized a sectarian, community-wide conflict as paramilitaries targeted civilians based on identity and many residents, particularly Catholics, refused to support police and military security efforts given their fear of state collusion, inadvertently benefiting the paramilitaries. Conversely, the Omagh district experienced more civil action on the part of police, protesters, and counterprotesters, which limited polarization and led to more outwardly oriented republican radicalization and minimal loyalist radicalization, containing violence. Overall, these cases suggest that examining on-the-ground interactions during the process of violence is necessary to explain civil action’s impact on the trajectory and intensity of violence within a community and within the larger intrastate conflict.