Police officers do have the same rights as every citizen when off-duty, but when they are acting as agents of the state they should be held very accountable for their malevolent actions (not mistakes, intentional ones). For instance, calling an officer a dirty name is not cause for said officer to demand identification and threaten you with arrest (happened to me when he was acting exactly like said name). Unless there are reasons for privacy, while working as agents of the state they shouldn't get any unnecessary privacy. The vast majority of (US at least) police are laudable, but not holding the bad ones accountable kills their reputation. We should be encouraging citizens to tape, not intimidating them.