In the aftermath of 9/11, the United States approved ‘enhanced’ interrogation methods that have been condemned as torture. The most notorious was controlled drowning, known as waterboarding. For Assignment, Hilary Andersson hears from those who approved, ran and suffered the programme in secret CIA prisons around the world. And she experiences some of the techniques herself. Does harsh interrogation yield reliable intelligence in the fight against terror? And what impact has the interrogation programme had on on-going conflicts – did it fuel support for ISIS? Produced by Linda Pressly(Photo: A man sits in a prison cell. Credit: Shutterstock)