(CN) – Police departments across the country are investing in body cameras as a response to calls for increased accountability in the wake of high-profile shootings, but a study released Monday found that juries are less likely to blame officers for incidents based on footage from body cameras versus dashboard cameras.
Laws regulating, and in some cases requiring, the use of body cameras for police have been passed in 34 states and the District of Columbia. Many were spurred by a 2013 study that showed police use of force dropped by 50 percent in Rialto, California, when officers wore body cameras by community pressure after a Missouri grand jury’s 2014 decision not to indict the officer who fatally shot unarmed teen Michael Brown – an incident for which no video recording was available.
It may seem obvious that video footage would help juries accurately assign blame in violent incidents. But researchers say a viewer’s judgment may hinge on the viewpoint of the camera from which footage is shot.
In a study published Monday in the journal Proceedings of the National Academy of Sciences, researchers found mock jurors were less likely to find that an officer acted intentionally when viewing footage from a body camera rather than watching the incident from the vantage point of a police car dashboard camera.
The study also showed that potential grand jurors were less likely to indict officers when they watched footage from a body camera than when they viewed an incident from a dash camera.
Researchers attributed the discrepancy, which was consistent across eight experiments, to the amount of time an officer was visible in the footage. Viewers were reluctant to assign blame to an officer they could not see, who was obscured behind a body camera. When researchers controlled for this factor by making visible the arms and legs of officers wearing body cameras, viewers assigned blame at an equal rate, regardless of whether they were shown footage from a body camera or a dash camera.
The results suggest that increased use of police video in criminal proceedings won’t increase just outcomes in the wake of police violence – unless we better understand the psychology of viewing them. More research is needed to understand the true impact police footage has on jurors and the general public, according to Broderick Turner, the study’s lead author and a social psychology researcher at Northwestern University’s Kellogg School of Management.
“Officers mostly don’t get indicted,” Turner said in an interview. “Regardless of whether there is body cam footage or dash cam footage, the baseline is really low. In some ways [this study is] just an extra caution that not understanding the influence that body cam footage could have to an already low indictment rate is a disservice to the world.”
Turner’s team showed participants footage from hundreds of publicly available police videos. In some cases, the researchers created videos to test their theories, for example by manipulating footage to change the amount of time the main actor was visible. Roughly half of the videos were shot from dash cameras while the other half came from body cameras, and the whole collection was randomized by algorithm to avoid any bias introduced during editing.
The team found that nearly 2,000 participants in eight different experiments were more likely to conclude that police acted intentionally when they watched footage from dash cameras rather than footage filmed from a camera affixed to the officer’s body.
The studies showed that viewers tend to assign intentionality to the person with the most “visual salience” – that is, the person who is most visually central in the video and who stands out the most. In videos from body cameras, the officer is rarely visible. But the more the screen time an officer had in each video, the more viewers were willing to assign intent behind the officer’s actions, and therefore willing to assign blame for violence.
To test this, researchers made multiple videos where actors were “overtly intentional,” for example, tipping over a cup or kicking over a trashcan. These were shot from a body camera, but with varying degrees of visibility for the actor. In some, the actor wearing the body camera never appeared in the frame. In others, researchers made sure the actor’s arms and legs regularly came into view.
The results showed that viewers were far more willing to assign blame to visible actors than those obscured behind the body cam. When an actor wearing a body camera was visible, viewers assigned intentionality equally, regardless of whether the footage came from dash cameras or from body cameras.
“The proportion of time on screen, number of appearances, and time per appearances were fixed factors predicting intentionality judgments for all 26 videos used in our experiments,” the researchers wrote. And of those factors, “only the proportion of time on screen predicted viewers’ intentionality judgments.”
Turner said there’s a reason for that.
“The way our cognitive system works is, we need a person there to attach a judgment to,” Turner said. “The way most body cam footage works is, the person who is doing the action is not usually seen.”
Turner said one take away could be that all officers should wear body cams. That way, each officer’s body camera would provide the third-person perspective that a dash camera provides.
“That’s like a human dash cam,” he said.
Until then, Turner advised caution when viewing footage from a body camera:
“When you see body cam footage, ask yourself the question: what am I not seeing?”
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