Maybe I'm the only one but from your description I'd say you got a little bit of what was coming to you.
First off, never, and I do mean NEVER bring you your family's connections. That was just dumb and secondly, if he wants to be the ******* so be it, don't be one back. You probably could have gotten away with a simple loud exhaust ticket if you had kept quiet and just let him have is power trip.
Secondly, why did you disagree with the officer outright? You pretty much belittled him when he was doing his job. Would you like it if somebody came up to you and started mouthing off about how dumb your were? I doubt it. Instead, disagree with him by asking him where you almost hit these kids. Then tell him you didn't see anybody. If he wants to say tuff **** just ask him if he's got a witness because as far as you can tell nobody was hit
. That's how you respectfully disagree without striking a nerve.
But hey, I wasn't there so I won't make any more judgement calls. Obviously what he did was complete BS but you didn't make things any better by bringing up your mother's political ties. Heck, my Mom's been mayor, depute mayor, township committee, AND police commissioner. I've been pulled over COUNTLESS times with harrasement from cops. They eventually radio in my license and registration then get the "word" from the dispatch that the last name is on some kind of list and they come back all apologetic (when pulled over for BS reasons).
My last point and this might really tick you off but he could easily get away with punching out your window. You said the door didn't open, that's probably illegal so he could have said that you wouldn't open the door and the law is on his side. Since he couldn't open the door he had to get to you somehow or another... it's sick and stupid but that's how they can get away with murder. Hence my point of this reply, don't piss off a cop, it'll never turn out good for you.