The Use of Body Worn Videos in Police Operations: A Prospective Meta-Analysis of Six Randomized Controlled Trials

• In Event: Evidence-Based Crime Policy IV

Abstract

Body worn videos (BWVs) in police operations are considered a useful tool for tackling police use of force and complaints against officers. They are expected to lead to increased prosecution rates and improve evidence capture by the police, which, in turn, might ultimately help to enhance transparency and police legitimacy. Yet, with the exception of Ariel and Farrar’s (2014) study in Rialto (California), the effects of BWVs remain untested. The Rialto experiment reported that BWVs reduce use of force by 50% (in comparison with controlled conditions) and by more than 90% for before-after reductions in complaints against officers. In this paper, we report findings from a multi-site randomized controlled trial involving six forces across three nations. During six months, we randomly-assigned nearly 500 officers across forces to “experimental-shifts” in which they were equipped with BWVs that recorded all contacts with the public and to “control-shifts” without BWVs. Based on data captured on more than 3,000 shifts, we report the effect of BWVs using prospective meta-analysis methods.

Author

• Barak Ariel, Cambridge University / Hebrew University