We document the connection between land reform and violent crime in Mexico using the counter-reform (the transformation of ejido land into private property) carried out in 1992. Using data at a municipality level, we exploit the fact that municipalities have different exposure to the reform. We report a significant impact of the land reform on the number of murders: In those municipalities with a higher proportion of social land, and therefore more exposure to the land reform, the number of murders decreased more than in those municipalities less exposed to the land reform. Our results suggest that clearly specified and consistently enforced land rights reduce gains from violence, therefore leading to lower levels of violence as measured by the number of murders.