Louis Theroux: By Reason of Insanity

In this first of two parts, Louis spends time with patients attempting to come to terms with their crimes and the clinicians entrusted with helping to make them safe. And he investigates the difficult question - when is a patient with a serious crime in their past ready to be returned to the outside world?

In the second episode of this two-part series, Louis spends time with patients whose personalities are so intertwined with their illness that 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.