Currently they use dash mounted cameras with mics and they can't turn them off on some models. I was hoping they would have something like a helmet mounted GoPro or best mounted one. Yes, it won't see everything, but since they call 50 officers to a car ticket, someone will capture it.
Loss of tape should come with fines. Leo should be held to the highest of standards. No off duty for mistakes, you are fired.
The other case I heard where it helped them was some spoiled brats were drunk in public and called in a attempted rape charge. Tapes probed otherwise and had the girls talking about making the false claim in tape. They got busted pretty hard from what I recall.