Monitoring Police with Body-Worn Cameras: Evidence from Chicago

Abstract

Using data from the Chicago Police Department on complaints filed by civilians, and reports of force by officers, this paper estimates the effect of body-worn cameras (BWCs) of officer and civilian behavior. Utilizing a two-way fixed effects design with a staggered adoption of body-worn cameras across 22 policing districts to almost 12,000 officers, I find an estimated 33% reduction in use-of-force complaints following the usage of body-worn cameras. This effect is driven in large part by a reduction in white officer-black civilian use-of-force complaints. Additionally, I find a corresponding 42% reduction in officers reporting striking a civilian and a large though less significant reduction in firearm usage, potential mechanisms for the reduction in complaints. Importantly, these reductions are not associated with an increase in injury to officers or any increase in force from civilians. However, I find that officers make fewer arrests for narcotics and cannabis possession following BWC adoption, evidence that body-worn cameras lead to de-policing. Taken together, this suggests that body-worn cameras are an effective technology at deterring unnecessary force but need to considered holistically before discerning whether their benefits outweigh their costs.