I feel like the solution is a "taking a shit" button which flags that chunk of the video. That way unless there is some suspicion that a crime happened in that chunk of time it goes unwatched.
Just have it time limited so that every sixty seconds they get a quick audible countdown to point away from their exposed body part at the roll of toilet paper or wall of the urinal. They can't beat someone and keep breaking to arrange a fake shot from atop a toilet.
Cop walks into the toilet, closes the door, turns off the camera. Immediately exits, jumps into police car to find and beat some people they don't like, then turns around, goes back to the toilet and turns it back on before opening the door to leave.