Naked Violence (1969)

About the search for an adult who pushed a classroom full of troubled teens to gang-rape and murder their female teacher. A hard-bitten Police Inspector named Liberti is put on the case and sets about brutally interrogating the young punks. He finally settles on a blond boy named Fiorello as the one most likely to squeal, but when he jumps from a rooftop, Liberti knows there is more to the teacher's murder than meets the eye.