Shakedown (1988)

A drug dealer shoots a corrupt police officer. Though the drug dealer admits his guilt, he pleads self-defense. His lawyer, Roland Dalton, and renegade loner NYPD narcotics agent Richie Marks, pursue evidence in his favor. They encounter difficulties from other corrupt police officers, drug dealers, and various street scum. Dalton's life is further complicated by the fact that the prosecuting attorney is a former lover.