Psychology Case Study: Dissociative Identity Disorder Case of Billy Milligan

Instructor: Elisha Madison

Elisha is a writer, editor, and aspiring novelist. She has a Master's degree in Ancient Celtic History & Mythology and another Masters in Museum Studies.

Billy Milligan was a man with dissociative identity disorder that robbed people and raped three women. This lesson discusses his unique circumstances and how they affected psychology as a whole.

Dissociative Identity Disorder

Dissociative Identity Disorder (DID) is the disorder when someone has a ''disruption of identity''. Originally called Multiple Personality Disorder (MPD), this disorder means an individual has two or more personalities, with one active while the others lie dormant. This results in chunks of time being lost, for the main personality. The additional personalities can be any age or gender and tend to have unique behaviors, speech patterns, and actions.

Most psychologists agree that DID usually results from a traumatic experience(s). Individuals use their alter personalities to escape from the emotional or physical abuse of this trauma.

Billy Milligan

Billy Milligan is one of the most famous cases of DID. He was the first person in the United States with this disorder who was found not guilty of his crimes by reason of insanity. During the trial, many psychologists argued about the existence of DID and assumed it was ploy rather than a valid disorder. Since Billy Milligan's was found not guilty by reason of insanity, it gave credence to the disorder.

Billy Milligan was born on Valentine's Day, 1955. His father, John Morrison, had an affair with his mother which resulted in two children. Morrison was a comedian who suffered from depression and committed suicide when Milligan was only four. This may have been the start of Billy's disorder, but it is unknown. Eventually, Billy's mother married Chalmers Milligan when Billy was eight years old. Billy later accused his step-father of raping him, burying him alive, and hanging him by his fingers and toes. However, this was never proven, although it could be a definite reason for Billy's dissociate identity disorder.


The Personalities

During his lifetime it was determined that Billy had twenty-four separate personalities. He gained new ones during his treatment, because of the environment of the health facilities and the assessment of the doctors. Each of the personalities had their time in the ''spotlight'' as Billy called it. There were two subsections of personalities. The first ones were protective and usually good people. The second ones were the ''undesirables'', which often got Billy into trouble, so Billy did not like to mention them. The personalities from the first group were a few that were seen the most:

  • Ragen - This is a 23-year-old Yugoslavian, and he was the strongest in physical ability of all the personalities. Also called ''the keeper of the hate'', Ragan spoke with an accent and was there to protect Billy and the weaker personalities from the harsher world outside. He also is the personality that committed the robberies.
  • Adalana - This is one of the very few female personalities. She was 19 and a lesbian who desired love, and was willing to use violence to obtain it. She also is the main reason for the court cases, being the active personality during the rapes. She is also one of the few personalities who could take control without permission.
  • Arthur - This personality was an intelligent 22 year old with an English accent. He was very strategic and could choose when to be the active personality.
  • Allen - The only smoker in the group, he was often the one to help Billy get out of trouble. He assumed control when Billy needed to talk his way out of a bad situation. He was also right-handed, when Billy was actually left handed.
  • David - This personality was put in charge when Billy experienced pain. Only 8 years old, he dealt with the harshness of reality when all of the other personalities could not.

The Crimes

Billy Milligan's personalities committed a variety of crimes. Ragen robbed stores and people, qhile Adalana raped three girls in the late 1970's out of a desire to be loved. When Milligan was put on trial, his lawyer and the police that arrested him realized that there was something severely wrong. Eventually, after a few medical assessments and tests, the court decided to deem Billy, not guilty by reason of insanity. He was then sent to Athens Mental Health Center.

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