Primal Fear (1996)

An arrogant, high-powered attorney takes on the case of a poor altar boy found running away from the scene of the grisly murder of the bishop who has taken him in. The case gets a lot more complex when the accused reveals that there may or may not have been a "third person" in the room during the murder. The intensity builds when a surprise twist alters everyone's perception of the crime and what really happened...