In the aftermath of the protests following the 2014 shooting death of Michael Brown, the Department of Justice investigated the Ferguson, Missouri police. Its report asserted that Ferguson police’s “law-enforcement efforts are focused on generating revenue.” The DOJ claimed the Ferguson PD had engineered a racist, lucrative revenue model wherein officers targeted black drivers for stops and searches, penalizing them with citations and issuing arrest warrants for missed payments at a much higher rate than nonblack drivers. Body cameras equipped with facial recognition, rather than holding police accountable, would enable such a system by making simply walking outside a risk.

The patents also imagine different types of audio triggers for the cameras. “Raised voices” and “vocal stress” could activate them, as could the sound of gunfire. Police already use “acoustic surveillance” to listen for gunfire, particularly in cities like Chicago and Oakland that struggle with gun violence. The patents also propose neighborhood specificity: Police departments could create geofences, making it so that police entering specific areas always trigger the cameras. And finally, the patents also cover biometric triggering events. Officers would be equipped with sensors measuring their vitals: heart rate, breathing, blood pressure, etc. When “biometric stress” is detected, the cameras will begin to record.

Further reading: How a tiny website became the police’s go-to genealogy database

Auto-record isn’t entirely new, or entirely foolproof. In July of last year, Justine Damond, an unarmed Australian woman, was shot and killed by Minneapolis police responding to her 911 call. Both responding officers were wearing body cameras, and as media coverage would later point out, responding officers that night were equipped with Axon Signal, a device that automatically turns on officer body cameras in the event of a crash or shooting, but no footage was ever recorded of that night. Neither officer turned on his individual camera or the vehicle-equipped camera.

Technological stopgaps and fail-safes can only go so far in maintaining consistent standards for police accountability. A March report from the tech-policy think tank Upturn found that 40 percent of body-camera footage from officer-involved shootings in 2017 was never released to the public. Further, many departments have moved to rewrite their internal policies to make it more difficult for the public to request footage.

“If the goal of body cameras is to capture when force is used, then activation upon when a gun is drawn or fired, a siren is turned on, or perhaps even when the police car door opens might make sense,” Hartzog said. As he explains, having cameras set to “off” by default, but triggered in specific scenarios, can guard against “purpose drift,” where technology is introduced for one purpose then used for another. The triggers, ideally, would maintain consistency.

Having cameras always on, always recording, may be a surveillance nightmare, but leaving it completely up to officer discretion, even with fail-safes, risks manipulation or misconduct. In certain spaces of social life, like airports, we’re willing to accept a forced lack of anonymity. But when we let police set the boundaries of permanent suspicion, we risk a world where going out in public is a transaction: We have to exchange anonymity for the right to be assumed innocent.

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