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Testing the Effects of Body Worn Video on Police Use of Force during Arrest: A Randomised Controlled Trial

NCJ Number
Date Published
107 pages

This document reports on a study that tested the effect of body-worn cameras within a large U.K. force in a six-month randomized controlled trial, and discusses the various issues surrounding the implementation of body-worn camera experiments.


This dissertation examines the effects of body-worn cameras within Birmingham South, a large U.K. police force, in a six-month randomized controlled trial; the research study observed the effects within pre-specified force categories. Overall, a 50 percent reduction in the odds of force being used was recorded when body-worn cameras were present, compared to control conditions. This result was interpreted to be a result of the deterrence effect that body-worn cameras have on officers, offenders, or both. There was no discernible effect on categories of force responses that were more aggressive than open-hand tactics. Additionally, 40 percent more force was detected in treatment conditions for handcuffing compliant suspects, which was contextualized as enhanced transparency and accountability rather than a backfiring effect. The study also documented a 65 percent reduction in recorded injuries to persons arrested, however it also demonstrated a corresponding increase in reported injuries to officers, which the author attributes to improved confidence in reporting by officers rather than the cameras creating more aggression towards officers.

Date Published: January 1, 2015