Police repression is a common feature of street protests around the world but evidence about its impact on dissident behavior is limited. We provide an empirical analysis of people linked to a student killed by a stray bullet coming from a policeman during a large protest. Using administrative data on daily school attendance, we follow his schoolmates and those living nearby the shooting in hundreds of protest and non-protest days to estimate whether police repression affected their protest behavior. We find that repression causes a temporary deterrence effect but only on students with social (rather than geographic) links to the victim. Moreover, we show that police violence increased adherence to a student-led boycott two years after the shooting and had negative educational consequences for students. These findings cast doubt on the effectiveness of police repression in quieting dissent and ensuring public safety.