Who can perform a Citizens arrest......?

Leaving aside any legalities, an "out of control police officer" would have a weapon and, most likely, more training than you. And how do you determine he is out of control? If you attempt to tackle him to arrest him and he shoots someone, accidentally or on purpose, how are you going to feel?

Now, if an officer is truly out of control and already shooting people, do what you got to do.

Oooo - that's sticky as hell. And there's plenty of cops who get drunk and need to get arrested too. But the cops are "friends of the court" - they're sworn in before a judge - bla, bla, bla. That makes they pretty immune to arrest except by members of their own profession. You take one of these guys on, and he's likely to kill you and get away with it.

Why not try it? (but make sure you post the video, we need a laugh)

NO, another Policeman.