More On World’s First Study Of Body-worn Cameras In Action

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A groundbreaking study of body-worn cameras first reported by Force Science News 18 months ago has now been published in a professional journal, with additional commentary.

An abstract of the research can be accessed free of charge, with an option to buy the full study, by clicking here, which will take you to the website for the Journal of Quantitative Criminology.

The research comprised a yearlong experiment conducted at the Rialto (CA) PD, a mid-size agency that serves a population of 100,000 residents, more than half of them minorities. The city, home to a number of large-scale hard goods warehousers and shippers, experiences an above-average crime rate, with a homicide rate that is nearly 50% higher than the US average. More than 20% of the population lives below the federal poverty line.

For 12 months, Rialto’s 54 frontline officers all were assigned randomly to wear or not wear Taser HD Axon Flex video/audio cameras attached to their clothing during each of their 12-hr. shifts. On shifts when they wore cameras, “the officers were instructed to have them on during every encounter with members of the public, with the exception of incidents involving sexual assaults of minors and dealing with police informants,” the study team explains.

Nearly 1,000 shifts around the clock were monitored in all, and all participating officers experienced both camera and non-camera working conditions.

Recorded video was automatically uploaded at the end of each tour, and the research team had full access to this “rich” database in what they claim was the world’s first test of the effect of body cams on police-subject interactions.

The results were dramatic.

For three years prior to the experiment, the PD posted roughly 65 use-of-force incidents per year. (UOF was considered “physical force that is greater than basic control or ‘compliance holds’ ” and included OC spray, baton strikes, TASER deployment, K9 bites, or firearms.) In the year before the experiment, 24 citizens lodged grievances against officers.

During the experimental period, the UOF rate dropped significantly, to 25 incidents total, a reduction of 58% to 64% compared to previous years. Only eight of the incidents occurred when officers were wearing body cams. In other words, during the test period the likelihood of force being used was roughly doubled when cameras were not deployed.

Citizen complaints plunged to a total of 3, a precipitous drop of 88%.

The research team’s commentary on these findings includes these observations:

  • Extensive research shows that people tend to “adhere to social norms and change their conduct” once they’re aware that their behavior is being observed. Under camera scrutiny, they “become more conscious that unacceptable behaviors will be captured on film,” with detection “perceived as certain.” Body-worn cameras (BWCs) convey a “straight-forward, pragmatic message: ‘You are being watched, videotaped, and expected to follow the rules.’ “
  • This “self-awareness effect” caused by the camera’s “neutral third eye” affects the psyches of officers and suspects alike, prompting suspects to “cool down” aggressive actions and deterring officers “from reacting with excessive or unnecessary force.” Neither party wants to “get caught engaging in socially undesirable behavior that may have costly consequences.”
  • “[E]ven police subcultures of acceptable but illegitimate force responses are likely to be affected by the cameras,” the researchers write, “because misconduct cannot go undetected…. Police-public encounters become more transparent and the curtain of silence that protects misconduct can more easily be unveiled….” On the other hand, cameras may “force” officers “to endure stressful situations and arguably accept some forms of disrespect that without the cameras [they] would normally not.”
  • The study revealed an interesting “spillover effect.” Overall, the use of force and citizen complaints declined both when cameras were in use and when they weren’t, the researchers point out. They speculate that this may reflect a conscious effort by officers without cameras during a given shift to competitively improve their behavior to favorably match that of fellow officers who had the “advantage” of wearing a body cam.
  • There’s a “training potential” in body-worn videos. The footage “can be used to ‘coach’ officers about how they conduct themselves,” the researchers write. “We envision future police training to incorporate one-on-one sessions in which junior officers train with their own footage…and potentially improve their demeanor when dealing with suspects, victims, and witnesses.”
  • While the researchers consider a cost/benefit analysis to favor BWCs, they acknowledge that one “price” is presently unclear: “What are the direct and indirect costs of storing, sharing, and managing digital evidence?” As the “velocity and volume of data” grow exponentially over time, “user licenses, storage space, security costs, maintenance, and system upgrades can potentially translate into billions of dollars worldwide.”
  • However, “the cost of not having video footage may have direct implications on decisions to prosecute or on criminal proceedings more generally.” Historically, testimony by officers in court against defendants has “carried tremendous weight…. Yet it is very likely that defense attorneys, judges, the jury, and the public as a whole would steadfastly assign more weight to digital evidence…. [W]ould district attorneys…be reluctant to prosecute when there is no evidence from body-worn devices to corroborate the testimony of the officer… Would cases be dismissed if arrests or stop-and-frisk were conducted without a body-worn video, given the possible violation of human rights? Will officers’ credibility in court be assumed to be violated when police-public encounters are not recorded?”

Time will tell whether such potential consequences will prove to offset the benefits of BWCs, the researchers say.

Meantime, “mistrust and a lack of confidence…already characterize some communities’ perception of their local police,” they note. “It may take just one or a handful of cases” of unnecessary or excessive force to further “damage the legitimacy of the police” and inflict “tremendous costs” on agencies already struggling financially “in an era of austerity….

“Completely eradicating illegitimate use-of-force is unlikely, as some force will always be required against some offenders in some circumstances. Any approach should still allow for legitimate use-of-force…but for all other circumstances, a reductionist approach should aim to dramatically ‘cool down’ encounters.”

Based on the findings of this study, which the research team urges other departments to replicate in their own jurisdictions, BWCs appear to be a potentially valuable tool in achieving that goal, while “enhancing police legitimacy and transparency, increasing prosecution rates, and improving evidence capture….”

The researchers authoring the study are William Farrar, chief of Rialto PD, and Drs. Barak Ariel and Alex Sutherland of the Institute of Criminology at the University of Cambridge in England.

Our original report on this research, based in large part on an interview with Chief Farrar, who directly managed the experiment, can be accessed by clicking here. 

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