Using new data at the police department level, I propose an identification strategy to estimate the causal effect that … police militarization has on reducing violent crime. I show that previous estimates are likely to be contaminated by … the displacement of violent crime to neighboring areas. Police departments overmilitarize because they do not consider …

An influential literature has used the aftermath of terrorist attacks to estimate large effects of police street … circumstances. This paper exploits a natural experiment that aimed to increase police presence in more than 6,000 well-defined areas … by police officers, we first document exogenous and discontinuous changes in patrolling intensity. We do not find that …