Correlational agency data but not experimental trials show body cameras reduce force

Evidence

An emerging literature is documenting the efficacy of implementing bodyworn cameras. In a number of agencies that have adopted body cameras, the use of force has been reduced. For example, in Mesa, Arizona; Rialto, California; and Orlando, Florida, use of force incidents decreased by 75 percent, 60 percent, and 53 percent, respectively (Ariel, Farrar, & Sutherland, 2015; Jennings, Lynch, & Fridell, 2015; cited in Miller, Toliver, & Police Executive Research Forum, 2014). The rate at which civilians filed complaints also dropped at these agencies. An 18-month randomized controlled trial of more than 2,000 Metropolitan Police Department officers in Washington, DC, however, found that body-worn cameras did not have a significant effect on officer behavior (Yokum, Ravishankar, & Coppock, 2017). Specifically, officers randomly assigned to wear the cameras used force and received civilian complaints at the same rate as officers who were not equipped with the cameras. — Joseph Avery, Jim Sidanius, Joel Cooper, Gregory Davis, Amanda N., Bias in the Law, 431

Categorization

• XREF: Directly bears on the reader’s question about whether surveillance or accountability interventions actually change measured behavior versus merely professed intentions — a version of the conviction-vs-measured-action gap in institutional context.
• SEED: Possible angle: ‘When the experiment fails the narrative’ — the DC RCT contradicts the widely-cited agency case studies (Mesa 75%, Rialto 60%), a cautionary instance of selection bias in police-reform evidence.
• SHARE: This RCT-vs-agency-data contrast would interest anyone tracking evidence quality in criminal justice reform.
• corroborated: 2 independent passages support this claim — Joseph Avery, Jim Sidanius, Joel Cooper, Gregory Davis, Amanda N., Bias in the Law: A Definitive Look at…, 431