Psychologist Richard Samuels testified for the defense that Arias suffered from post-traumatic stress disorder and dissociative amnesia, which explained why she couldn't recall much from the day of the killing.
Hassan, a Somerville, Mass. mental health counselor who has helped scores of former Dahn members, says the group uses deceptive recruitment and mind-control techniques to create a dissociative disorder among followers, splitting them off from their families and value systems.