Anarchism

There's the scenario where the camera was made to malfunction on purpose to cover a crime done by a cop, and legitimate malfunctions. Let's say legitimate malfunctions are the large majority of cases to be nice to the cops.

You check the camera's function periodically. Yes, it is possible that once in a blue moon, it breaks during the day despite an equipment check being done every morning, and someone walks free. People walk free out of court all the time due to lack of evidence, the question we're asking ourselves is whether we'll be talking about reasonable numbers. My priorities are minimizing the number of innocents in prison, then minimizing the power an abusive cop can have, and only after all that minimizing the number of bad guys roaming around freely. You're free to think otherwise but do note that the justice system of every developed country adopts the same priorities I do in theory

OK - so, intense public interactions don't happen every day. Most camera malfunctions should happen on days where nothing happens, get a minor traffic stop challenged and dropped, mostly things that went fine. Occasionally someone will do something serious and walk free because of it. Due to the randomness of a malfunction and how often these events happen on a baseline, this is unlikely. Most of the time you're going to find out about a malfunction in the morning gear check anyway before the camera got a chance to render a cop interaction inadmissible in court.

Now, the minority of cases where the cop purposefully triggered a malfunction (puts the SD card in a microwave). These do not happen randomly. They happen when the cops needs it to happen, because he's done something wrong. These are the moments where a citizen got beat up, when someone got choked, when their weapon got discharged - the serious shit

Now you ask yourself the question, a bank was robbed and the cop is at the trial. His camera malfunctioned. How likely is it that he tampered with the evidence, and should you believe him? I believe no.