Working in partnership with local police agencies, we conducted six coordinated field experiments in Brazil, Colombia, Liberia, Pakistan, the Philippines, and Uganda. We collaborated with the police to implement locally appropriate increases in community policing practices. We planned for risks involved in partnering with the police by soliciting reports of police abuse and carefully selecting the areas we worked in and the police units we partnered with. We randomly assigned areas to either the community policing practices or a control group. Our interventions reached approximately 9 million people in 516 treated areas. At the end line, we surveyed 18,382 citizens and 874 police officers and obtained crime data from the police. We conducted experiments in multiple settings with common measures to strengthen the generalizability of our findings and preregistered a joint analysis of the six studies to reduce the risk of publication bias.
November 26, 2021