Louis Theroux: By Reason of Insanity

Louis immerses himself in the world of Ohio’s State Psychiatric Hospitals, meeting patients who have committed crimes - at times horrifically violent - while in the grip of severe mental illness.

In the second episode of this two-part series, Louis spends time with patients whose personalities are so intertwined with their illness it makes them more difficult to treat. In doing so he examines the grey area between criminal actions and medical symptoms, and investigates how we define insanity.