70 pages 2 hours read

Daniel Keyes

The Minds of Billy Milligan

Nonfiction | Biography | Adult | Published in 1981

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Summary and Study Guide


The Minds of Billy Milligan (1981) is a nonfiction work by Daniel Keyes, documenting the life and experiences of William Stanley “Billy” Milligan, the first defendant found not guilty by reason of insanity because of dissociative identity disorder (DID). The book follows Milligan’s early life experiences that led to his illness, arrest, and trial after the rapes of three women on the Ohio State University campus, as well as the years he spent in different psychiatric facilities, receiving treatment, until 1982. The book explores themes of self and identity; the interplay of law, psychology, and media; and the complexities of DID.

Daniel Keyes (1927-2014) authored the critically acclaimed science fiction short story “Flowers for Algernon” (1959), which inspired his award-winning novel of the same name and was later adapted into a stage play. Keyes wrote other novels, as well as nonfiction works, the first of which was The Minds of Billy Milligan. It won Germany’s Kurd Lasswitz Award for Best Book by a Foreign Author and was nominated for the Edgar Award by the Mystery Writers of America.

This guide is based on the 2018 Orion Kindle Edition.

Content Warning: The book and this guide contain detailed accounts of crime, including sexual assault; refer to death by suicide; and discuss trauma and abuse as well as institutionalization and mental health treatment. In addition, the book contains outdated or insensitive portrayals of mental health disorders, including use of the term “multiple personality disorder.”


The Minds of Billy Milligan has three parts. The first part covers William Stanley “Billy” Milligan’s arrest after three women were raped and robbed across a two-week span in October 1977 on the Ohio State University campus. Following the assaults, his attorneys, medical professionals, and Milligan himself discovered that he had dissociative identity disorder (DID).

Noticing Milligan’s strange and changeable behavior, including his constant assertion that he remembered nothing of the crimes, his attorneys decided to enter an insanity plea and obtain a psychological evaluation. The results of the evaluation yielded a diagnosis of “multiple personality disorder,” and 10 different “alters” (or alternate identities) were revealed over the course of multiple sessions. Milligan’s experience of sadistic and sexual abuse by his stepfather, Chalmer Milligan, appeared to have triggered his dissociation.

Milligan’s attorneys arranged for his transfer to Harding Hospital, where he began receiving treatment for his illness before the trial. He attained partial identity fusion through therapy and was ruled competent to stand trial. However, evidence of his illness was irrefutable, as multiple mental health professionals and experts testified. Milligan’s case was heard solely by a judge, without a jury trial, and both the prosecution and defense agreed that Milligan committed the crimes but noted that they were a function of his illness.

Milligan became the first person declared not guilty by reason of insanity because of “multiple personality disorder” (now called dissociative identity disorder [DID]). He was ordered to continue receiving treatment at the Athens Mental Health Center and greatly benefited from the open ward there and the expertise of Dr. David Caul. Interest in Milligan continued well after the case, and Dr. Caul introduced Milligan to Daniel Keyes, “the writer,” when Milligan expressed interest in telling his life story. During sessions with Dr. Caul and Keyes, Milligan eventually revealed 24 different alters. When Billy, the core identity, finally learned of his illness, as well as the existence of 24 different alters, he finally began to attain fusion. This yielded “the Teacher,” an unfragmented Billy.

The second part of the book recounts the events of Milligan’s life up to the moment of his arrest, as recalled in great detail by the Teacher. Milligan’s biological father, Johnny Morrison, was a musician and comedian who died by suicide when Milligan was young. On one occasion, Milligan witnessed Johnny overdose on alcohol and pills, after which he experienced his first dissociation: “Christene,” a three-year-old girl, emerged. Over the next few years, more alters began to develop, but the major dissociation happened when Milligan was nine and Chalmer sexually abused him for the first time. He began to dissociate more frequently as time passed, experiencing bouts of amnesia as different alters “[stole] time.” Milligan’s family and teachers reported on his trancelike states and extremely changeable demeanor. At age 15, he was briefly placed in Colombus State Hospital for treatment but was misdiagnosed with “hysterical neurosis.”

When Billy, the core self, attempted death by suicide at 16 by trying to jump from the school’s roof, Ragen, one of the alters, stopped him and put him to sleep. Arthur, another alter, deduced the presence and purposes of the others and, with Ragen’s input, created rules and structures that dictated how the others ought to operate. After being expelled from school, Milligan spent months working odd jobs that aligned with the different alters’ talents and interests. After a run-in with some sex workers, however, Milligan was accused of rape and assault; he was convicted and sent to a youth correctional facility, where he spent two years.

Once Milligan exited the facility, Arthur reinforced the strict rules of conduct for the different alters to ensure that they stayed out of trouble. Some alters became classified “undesirable” and were banished from consciousness for various misdemeanors; the others continued to work odd jobs and survive. However, over time, Arthur’s dominance weakened, and some of the “undesirables” began to steal time, dealing drugs and conducting other criminal behavior. Milligan was arrested for aggravated robbery after two of his alters robbed a drugstore, as well as some men at a roadside rest stop, and he spent another two years in prison.

After Milligan was released on parole, he fell back into the pattern of working odd jobs and losing employment when the mix-up between his different alters began to intensify. Worried about paying bills, Ragen set out on three different occasions to rob someone on the university campus. All three times, Adalana, Phillip, and Kevin, three other alters, took consciousness from Ragen to rape and rob the women; thus, Ragen returned home each time with no memory or awareness of the incidents. Milligan was eventually arrested again.

The third part of the book details Milligan’s journey in different mental health facilities following his trial. At the Athens facility, he began to make progress under Dr. Caul. However, Milligan’s increasing freedom and privileges earned Dr. Caul and Athens bad publicity. This led Milligan to grow increasingly depressed and agitated, and after some regressive incidents, he was moved to Lima State Hospital, a maximum-security institute with a horrific reputation. Despite the numerous hearings at which multiple experts in the field offered testimony backing Milligan’s transfer back to Athens, he spent two and a half years at maximum-security facilities, receiving subpar treatment and active harassment. The writer remained in touch with Milligan throughout this time, witnessing his deterioration.

Eventually, in 1982, Milligan was transferred back to the Athens facility, and Dr. Caul began working on undoing the damage of the previous few years. At the time of the book’s publication, Milligan remained fragmented again; the Teacher had disappeared and had not resurfaced, and communication between the different alters had deteriorated. Nevertheless, Milligan remained somewhat hopeful, as both medical experts and the local community seemed inclined to give him a second chance.

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