I don't understand what you're trying to say. You say it's a mistake to insist the camera be on at all times, but then you go ahead and say that that would be open to abuse?
It's a lot harder for opponents to argue against the idea of testimony enhancing equipment than it is for them to argue against equipment that strips the officer of discretion and privacy. So the use it when you want to version probably gets deployed faster and with less fuss.
I don't think a police officer needs a great deal of privacy while on duty, but I also don't mind giving them the ability to turn off recording devices when they use the toilet. I mean turn it off independently, without asking some overseer for permission.
