Cop Land (1997)

When hotheaded Superboy (Michael Rapaport) accidentally gets involved in an ugly racially-motivated incident, his uncle Ray Donlan (Harvey Keitel), a corrupt New York City cop, attempts to sweep it under the rug by helping fake his nephew's death. The bungled cover-up leads to investigations by idealistic Internal Affairs officer Moe Tilden (Robert De Niro) and Freddy Heflin (Sylvester Stallone), sheriff of the suburban New Jersey town where Donlan and his fellow crooked policemen live.