Think of it realistically. Nothing will stop you from being corrupt. But if you get caught there is a high chance you get removed form the force. Simple as that.

If anything, you will be able to shoot off the back of trucks. Multiple people. But shooting from inside cars, not sure. Would be something you can tweet to Motown.

Your uniform is based off your rank in the department.

Yes you can edit your post/topic as much as you want.

Crime really shouldn't be conspired a bad thing to do on the game. Crime is just as important as everything else, without it police would be almost useless. 45 minutes max sentence lets, people who choose the life of crime, have plenty of time to enjoy the game.