It's not a perfect solution either. There have been plenty of instances where cops "forget to turn on" or "accidently block" their cams. Even cases where, mysteriously, the cams are "accidentally" damaged or the data "corrupted".
Unfortunately seems like the only defense for these cases is livestreaming police interactions.
Cop unions should be illegal. (All other unions are fine)
Absolutely, and you can generalize that to any sort of requirements are worthless if they don't have as much teeth as the power they are trying to check.