Between the early 1990s and the mid-2010s, citizen security in Medellín dramatically improved and police violence declined. But residents’ trust in police stagnated. We evaluate a police-led effort to build trust through town-hall-style police–community meetings. In 174 treated neighborhoods – but not in 173 control neighborhoods – the police held more than 500 such meetings over a period of nine months. We find that the meetings induced small positive changes in perceptions of the police, though they did not alter trust in police per se – or crime reporting behavior, much less crime itself. We interpret these findings as evidence that voluntary informal contact between residents and police officers is a weak but not irrelevant policy for reshaping police–community relations.