If their aim was to break him, his interrogators apparently succeeded. By late November 2002, Mohammed al-Qahtani--a suspected Al Qaeda operative sometimes described as the 20th hijacker--was hearing voices, talking to imaginary people, and spending hours on end cowering in a corner of his Guantanamo cell with a sheet draped over him.
The role of doctors, psychiatrists, and psychologists in interrogations has been a source of considerable controversy, since it seemingly violates the medical professions' central tenet: "Do no harm."
Over the years, a handful of efforts to hold caregivers accountable for complicity in detainee abuse have come up empty. But human rights advocates are hoping this track record will soon change.