The Expert (1995)

Johnny's sister is brutally attacked and murdered by a sadistic serial killer. At the trial, he is sentenced to be electrocuted, but a bleeding heart liberal has the sentence commuted to a mental facility. Here, he will interact with other model prisoners and give talks at schools while he is being treated. The only problem is that Johnny, being a ex-special forces trainer, is coming to the prison to seek his own justice and that does not include rehabilitation.