Police cars have videos that cycle through when their lights are on...
What I'd love to see would be a system where regular cars could have video devices installed. Then, if something like that happens, you can file a complaint, give the evidence (video tape), and the police would take care of it. We're far too lenient with who we allow to drive in this country.
Some comedian had a suggestion (joke) a few years ago. Everyone gets a dart gun to be mounted to the front of their car. If the person in front of you does something wrong, you shoot a dart at their car. Police remove any vehicles with 3 or more darts from the road.