Quincy, M.E. - Season 8 Episode 6 Sleeping Dogs

Quincy has to testify in the court of a small town. The witnesses in the case are pressurized into lying and Harry Muller, a bullying murderer, goes free. Within half an hour of the court case having been dismissed Harry Muller is found dead. The six men in the shop where he died all say they killed him, firing one shot each from his gun. The police chief is happy to call the death self defense but Quincy knows that it was murder and insists he will find out which one of them really killed him.