Totally. I used to (briefly) work in law enforcement. Situations where a vehicle was used as a weapon against an officer were justified for emptying your weapon into the driver's head.

It's not much different for a cyclist. Accelerating while you're hooked on the mirror has one purpose... serious injury. I'd be revisiting the police to speak to a shift commander. If that doesn't get action then send letters to the mayor, police board and your largest newspaper.