Gun violence is an important problem across the United States. Due to limited data, it has been difficult to convincingly test the impacts of government policies on the quantity and geography of gunfire. This paper uses a new source of data on gunfire incidents, which does not suffer from selective underreporting common in other crime datasets, to measure the effects of juvenile curfews in Washington, DC. Juvenile curfews are a common, but extremely controversial, policy used in cities across the United States. Their goal is to reduce violent crime by keeping would-be offenders and victims indoors, but their net effect on public safety is ambiguous for several reasons. They might also increase distrust between law enforcement and city residents, so it is important to understand whether they are cost-effective. We use exogenous variation in the hours affected by the DC curfew, in regression discontinuity and difference-in-RD frameworks, to estimate the policy’s causal impact on gun violence. We find that, contrary to its goal of improving public safety, DC’s juvenile curfew increases the number of gunfire incidents by 69% during marginal hours.