Vigilante (film)

1983 film with Robert Forster and Fred Williamson. Eddy Marino (Forster) is just an average, law-abiding citizen in New York City, when suddenly his family is attacked and son murdered by a gang, and only one of the Gang-Bangers gets sentenced - 2 years in prison because of a corrupt judge - and Eddy gets pissed. He joins up with a vigilante squad led by Nick (Williamson).

Tropes used in Vigilante (film) include:

Asshole Victim: Rapists, drug dealers, murderers, pimps - you name it.
Jack Bauer Interrogation Technique / High Altitude Interrogation: Nick and his two pals beat up a drug dealer to find out his source. When he won't squeal, Nick hangs the guy out of a window.
Judge, Jury, and Executioner: Nick calls himself a judge and jury. The executioner is implied.
Obstructive Vigilantism: After a woman is raped in her building, an old woman tells the police that she did not see who did it, despite passing them on the stairs. She then gets into a van with Nick and the gang, driving around town looking for the guy.
Pimp Duds: Horace the pimp goes around in his pimp car, slappin' ho's who don't make enough.
Prison Rape / Shower Scene - Eddy is alone in the showers when a few guys try to do this to him, but fortunately the Cool Old Guy gives the lead prisoner a Megaton Punch and saves the day.
Van in Black: The vigilantes park their black van in the red light district, wait for Horace to show up and follow him.
Vigilante Man: Multiple characters form a squad that goes around doing what the cops can't.