Yeah, this kid could've been a punk, but since he was a Navy enlisted man, it's far less likely. Yes, every branch has its punks, but it's still far less likely. Based on the statements by witnesses, I'd up my bet from one buck to ten right now, that this kid was murdered for failure to show proper supplication in the face of a federal LEO, plain and simple.
MM
I think this was pure road rage on the part of the Marshall. The kid didn't know he was a Marshall, and according to several eye witnesses, was just trying to leave.
If this Marshall had a legitimate problem with the kid, he could have recorded to license number and followed though that way.
May he get a long stretch in the State pen to think about it.