So while body-cam footage is “very clearly a public interest record,” says Emily Shaw, the national policy manager at the Sunlight Foundation, it is also “just full of private information.”

What’s more, there’s no easy way to fix this. Normally, private information would be redacted out of public records. (The Sunlight Foundation recommends certain easy ways to do this for other kinds of records, such as putting all personal information-containing columns off to one side of a spreadsheet.) But there’s no simple way to compartmentalize the sensitive aspects of video footage. Video isn’t text: It’s dozens of frames per second, each its own potentially private visual. Redacting personal information out of the frame remains both expensive and unreliable, and it might not be possible with algorithms.

“If you just put a swirl blur on somebody’s face, it’s not very difficult to unswirl that blur, and then all of a sudden it’s un-redacted,” Shaw said.

The only effective redaction process might be for technicians to go through a video frame by frame—an exceptionally costly process. Even that might not be enough. “If you have additional data, then you can re-identify people who’ve been anonymized or intentionally anonymized,” Shaw said.

That technique is so prohibitive that some cities have declared the whole situation impossible and blanket-exempted footage from open-records requests. Others are attempting technical solutions: Seattle’s police department is trying to “auto-redact” videos, muting a video’s sound, blurring the picture, and posting it to a YouTube channel.

But some experts say that, if departments can’t deal with the high cost of Freedom of Information Act (FOIA) requests, then officers shouldn’t get body cameras.

“If the police cannot handle FOIA requests for body-cam footage, they should not use them,” said Jeramie Scott, a national security counsel at the Electronic Privacy Information Center (EPIC). “There should be no blanket FOIA exemptions for police body cameras.”

Scott thinks existing exemptions, which cover privacy and reducing potential harm to private citizens, work just fine for body cameras.

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If there’s any consensus among experts considering body camera policy, it’s about this: Most groups, including the ACLU, agree that individuals recorded by body cameras should have access to that footage.

Yet implementing even that provision is tricky, says Shaw.

“If there are several people in the video and some of them don’t want it to be public but one of them really does, what happens in that circumstance?,” she told me. “Even if you redact the person who doesn’t want to be seen there, everybody knows this person is an associate of this person who is visible.”

Alex Rosenblat, a researcher at Data and Society, said a policy could have particularly “shady consequences for the victims of domestic violence or sexual assault.”