AbstractThe city of Fernandópolis, located in the countryside of the state of São Paulo, Brazil, imposed a juvenile curfew in 2005. This decision was not made at the municipal or state level, but in a courtroom. Subsequently, other municipalities in the state of São Paulo decided to adopt a juvenile curfew. To assess the effect of the curfew on reducing crime, this paper uses the difference‐in‐differences estimation to compare its impact, relative to municipalities that did not adopt a curfew. The results suggest that the curfew led to a decrease of 17.9% in thieves per thousand inhabitants in municipalities that adopted it.