You can file a formal complaint.
Only problem is, unless EVERYONE who gets harassed by police files a complaint, it won't make a difference.
We need to flood police stations with complaints until the cowboys get under control, and the good cops are recognized for their efforts.
There are LOTS of good cops out there, and they let a lot go by. And you have to admit that most of us gun it or go racing when we shouldn't. If we get caught, it's the luck of the draw - there's no use complaining.
But if you are genuinely being unfairly harassed or discriminated, then it's worthwhile to make a complaint. A lot of the things I've heard on here warrant complaint, and the moderators on this website and other car websites should compile a web page purely for posting complaints that have been filed.
It would allow a national database of police complaints, listing date, state, officer name, rank, car, complaint, etc etc. Eventually, you would be able to tally up whose getting the majority of the complaints. Police have a database of us, why shouldn't we do the same?
Thankfully, there aren't as many cowboy-cops going around as there used to be.