The golf club beating was supposed to be just that, a beating. It got out of hand and it went overboard. They were never supposed to kill him nor were their intentions to kill him. End of the day, it was fucked up and they never should of did that. A few punches and a gun in his mouth would of done the trick. It was a brutal way to die and law enforcement never forgot about the brutality and went on a mission to nail all of them hard. Thats why they are so hard on michael and marty.
Marty will be out of jail the same time the "son of sam" gets released.