I generally don't agree with most of your comments but you are correct in this instance, IMHO. Our "CCRB" (Civilian complaint review board) is made up of Marxist lawyers and liberals and overseen by a city council that has an ex-black panther as one of its most visible members. How can a decent cop operate in areas where the majority of the citizenry has either been locked up or is related to someone who has?
I think the way to go is strong internal enforcement. The "rat squad" (to use old school NYPD terminology) isn't popular, but they are effective without being vindictive.