“Ramparts” was for the most part a solid effort mostly due to the script written by James Ellroy who wrote Pulp Fiction & Black Dahlia. In it Woody Harrelson plays a renegade cop with a dysfunctional family life whose life is falling apart. Joining him for the ride are; Ice Cube, Steve Buscemi, Sigourney Weaver and more. Not great but well worth a look.
Then we have “Brothers Rico” with Richard Conte and others whose names I won't bother reciting. Because this was a bad movie with no real redeaming qualities. In fact I fell asleep before it was over. Avoid
A better choice and a real killer B would be the 2003 Ron Shelton film Dark Blue. It is another renegade LA cop whose life is falling apart story but it is also written by James Ellroy so it is also very good. Kurt Russell leads the cast in this crime story set around the time of the Rodney King riots. Check it out here.