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Wearable video cameras are becoming standard issue here for American police. The cameras promise a technological answer to complaints about racial bias and excessive force. But, in fact, the benefits of body cameras are not well-established yet, and the police departments that rushed to buy them are now dealing with some unintended consequences. NPR's Martin Kaste reports.
MARTIN KASTE, BYLINE: The people who like body cameras often point to a study done in Rialto, California back in 2012. Researchers found that cops who wore cameras used force less often. Incidents dropped more than 50 percent. Sounds like that settles it, right?
ALEX SUTHERLAND: The Rialto study is one study. And it could be a fluke.
KASTE: That's one of the researchers who ran the study, Alex Sutherland of the University of Cambridge. He says Rialto was not a definitive answer on the effectiveness of cameras.
SUTHERLAND: It's a small department. The police chief was kind of involved in implementations. So, you know, if those things aren't present, then maybe these things - it wouldn't be as effective. But we just simply don't know that at the moment.
KASTE: Among the unanswered questions - did the cameras make the difference, or was it the cops' verbal warnings about being recorded? How important was the camera's novelty? After all, this was three years ago. Does the effect fade as people get used to the cameras? Sutherland says we can't say anything definitive until more studies are done in more places.
SUTHERLAND: If public money is being spent on this technology, the onus is certainly to make sure that it's being evaluated as it's being rolled out, rather than deciding that it works and then that's that.
KASTE: And it's not just money that's at stake. The cameras may have other kinds of costs. They may affect police morale and recruitment. Eugene O'Donnell is a former cop who now teaches at the John Jay College in New York. He says he would never encourage a young person to take a job in a police department that requires cameras.
EUGENE O'DONNELL: Because the whole atmosphere there tells you right at the outset that if there's a bad ending, you're going to be called a murderer. You're going to get death threats in your home. Who's going to do the job?
KASTE: This argument doesn't make any sense to the people who want to see more cameras. They say cops who behave correctly have nothing to fear from the video. But cops say it's more complicated. In private and on their anonymous blogs, they talk about how civilians see these videos differently than they do. For instance, take that now infamous video of a state trooper shooting a man at a gas station in South Carolina last fall, a man who was just reaching for his ID. A civilian sees a completely unprovoked shooting. But when a cop watches that video, he sees it a little differently.
ADAM PLANTINGA: I felt my stomach tense up because I've seen that. And this has nothing to do with whether the incident was justified or not. But I've seen that kind of quick movement before when people have emerged with a weapon.
KASTE: Adam Plantinga is a police sergeant in San Francisco. He's also an author, and he writes about the way police see the world and what they're watching for in suspects.
PLANTINGA: Sometimes, it's - they may wipe their hands on their pants. They may lower their head so to - lower their jaw to protect their neckline. It's sort of unconscious human behavior that means that there could be violence at any time.
KASTE: To be clear, Sergeant Plantinga supports the use of body cameras. But he hopes that people will keep in mind that video alone isn't always the whole story. And, finally, there's this. This is the body camera recording of the final moments of a rookie officer named Tyler Stewart in Flagstaff, Arizona.
(SOUNDBITE OF ARCHIVED RECORDING)
TYLER STEWART: How are you doing?
UNIDENTIFIED MAN #1: Good.
STEWART: Can we talk outside?
KASTE: This is late last month. He was out on a domestic dispute call. And when the boyfriend came out to talk, he had a gun hidden in his pocket.
(SOUNDBITE OF ARCHIVED RECORDING)
STEWART: Do you mind if I just pat down your pockets real quick? You don't have anything in here?
UNIDENTIFIED MAN #1: No, no.
STEWART: OK, nothing in here?
KASTE: Moments later, the man kills Stewart, then himself. Local media requested the video under the state public records law. The police complied last week with version of the video that stops short at the moment the gun appears. Police Chief Kevin Treadway says they drew the line there on the advice of the lawyers, but he'd rather not have had to release the video at all.
KEVIN TREADWAY: I guess if you're asking me the question, you know, the public right - does the public right to know in this particular case outweigh the pretty significant trauma that showing this on the nightly news has for the members of the family? You know, I have to say no.
KASTE: Flagstaff tried to do things right with body cameras. It followed expert recommendations and laid out a clear policy in advance on how the video should be stored and who'd get to see it - but this? This they weren't expecting.
TREADWAY: Even the model policies that we looked at didn't foresee this, you know, very specific kind of incident occurring.
KASTE: It's believed to be the first time a police body camera has captured the death of its wearer. Unfortunately, as the technology spreads, it won't be the last, giving police something else to think about as they're told to put the cameras on. Martin Kaste, NPR News.
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