Megan Nelson is a woman afflicted with multiple personality disorder, and the killer of her psychiatrist, Dr. Lillian Hampton, as a result of her illness.
History[]
Megan’s mother Carol died when Megan was three from a fall down the stairs, which was reported to have been from her drinking. As Carol and Megan's father Frank constantly fought, Megan was always afraid Frank bashed her to death. The traumatic experiences at such a tender age caused Megan to develop alternate personalities, which she’d switch between to barricade her psyche from her memories and dread.
Dr. Hampton was hired to treat Megan's problems, but her two alters, Bobby Walker and Nancy, were much too aggressive imprints in her mind to sort through and repair Megan's mental state. When the time came that Dr. Hampton was to try and convince Megan Carol wasn't murdered, Megan's alters were furious, resulting in Megan bludgeoning Dr. Hampton to death with her own award in a dissociative rage.
When Megan's condition came to light, as well as the process of her treatment, the detectives also believed Frank killed Dr. Hampton to bury Carol's death as a murder. However, Megan's alters eventually confessed angrily to the murders, saying Dr. Hampton was breaking Megan's defenses and manipulating her.
Because of her mental state, Megan was institutionalized at the very least until she was evaluated as no longer posing a danger to the public. (L&O: "Switch")