In the summer of 1984, Elizabeth Haysom, 20, met German-born Jens Soering, 18, while attending an orientation event at the University of Virginia. By winter, the young students had fallen in love. Their passionate affair, which included a frenzied exchange of telling love letters, culminated in the brutal double murder of Haysom’s parents in 1985.
A jury convicted Soering of orchestrating the crime along with Haysom. But he denied responsibility, claiming Haysom had psyched him up to kill her parents. While awaiting trial, Soering was diagnosed as having a condition known as shared psychotic disorder or folie à deux—a French word meaning “madness of two.”
Folie à Deux Explained
French psychiatrists Jean-Pierre Falret and Ernest-Charles Lasègue first described shared psychotic disorder, or folie à deux, in 1877, referring to delusional beliefs that transfer from a “primary” individual to one or more individuals (or “secondaries.”) Brian Holoyda, a forensic psychiatrist who has studied cult behavior and cult members’ efforts to utilize the insanity defense in connection with folie à deux, says there are certain characteristics that make a secondary more susceptible to a primary’s influence. These include emotional immaturity, dependence on others, social isolation, mental illness, cognitive deficits (impaired intelligence and judgment) and the duration/nature of the relationship. Longer duration and closer bonds are more commonly seen in these cases.
“Primaries tend to be more dominant in the relationship, whereas secondaries are passive and receptive to the primaries’ delusional material and directives,” Holoyda tells A&E True Crime.
Would Soering have committed murder if he had never met Haysom? Both had troubled home lives, but the love letters revealed Haysom’s desperate wish for her parents to die. Haysom, who later received a diagnosis of borderline personality disorder, was also the more dominant of the two.
“It is by no means rare for the close associate of a psychotic person to share his or her delusions,” wrote John Hamilton, a consulting forensic psychiatrist who examined Soering, in a 1986 report. It’s possible, Hamilton continued, that Soering’s dependent and immature personality traits predisposed him to believe Hayson’s pathological lies—and to act upon them.
A&E True Crime looks at several other notorious examples of folie à deux and the challenge it presents in the courts.
Michael and Dennis Ryan (Survivalist Cult)
During the 1980s, on a remote farm in southeast Nebraska, white supremacist Michael Ryan led a survivalist cult whose followers included his own teenage son Dennis. Ryan, who believed he heard the word of God, spread doomsday prophecies and instructed his followers to reject established government. He warned of heinous punishments if they didn’t comply. His warnings culminated in the torture and killing of both 5-year-old Luke Stice, a cult member’s son, and fellow group member James Thimm. Dennis Ryan, at the supposed order of his father, delivered the gunshot that killed Thimm.
Rodney Rehm, the defense attorney who represented Dennis Ryan, told The New York Times in a 1986 interview he believed Dennis was a killer, but stated that his client was mentally ill. In their early interactions, Rehm recalls Dennis being frightened, confused and not very communicative. He also seemed younger than his actual age.
“Dennis seemed totally under the control of his father when I first met him. The relationship changed by the end of the trial. He seemed more independent in his thoughts,” Rehm tells A&E True Crime.
Mental status at the time of an alleged crime is an important part of proof in homicide cases, Rehm explains. William Logan, a psychiatrist who served as an expert witness for the defense, diagnosed Dennis with folie à deux in connection with his father. He noted that Michael Ryan wielded a powerful influence over the boy’s life. Since the defense could not dispute Dennis’s actions, they focused on intent.
“The testimony of our experts gave us evidence of diminished capacity to form higher levels of intent such as premeditation. The argument was Dennis had been ‘brainwashed’ into his father’s bizarre belief system. It was partially accepted by the jury with the verdict of second-degree murder,” says Rehm.
Initially sentenced to life, Dennis received a new trial on a legal technicality. He pleaded guilty to the lesser charge of manslaughter and was released in 1997 after serving 12 years in prison.
Lawrence Bittaker and Roy Norris (The Toolbox Killers)
In 1979, Lawrence Bittaker and Roy Norris abducted, tortured and murdered five teenage girls. The duo earned the nickname “The Toolbox Killers” from the variety of instruments they used to torment their victims inside a van they dubbed the “Murder Mac.” Both had long criminal histories before they met at the California Men’s Colony prison in 1977. While incarcerated, they shared twisted and sadistic fantasies involving young girls, with Bittaker’s desires including murder. Their shared delusions spiraled into a plan that led to the brutal killing spree.
Like other cases, it’s hard to say if Norris would have committed murder on his own. Norris objected to killing their first victim, Lucinda Schaefer. It was Bittaker who insisted it had to be done.
Former FBI special agent John Douglas described Bittaker, diagnosed as borderline psychotic, as the most frightening individual he had ever profiled. Experts, including James Alan Fox, a professor of criminology at Northeastern University, and Jack Levin, a professor emeritus of sociology and criminology at Northeastern University, have identified Bittaker and Norris as a classic case of folie à deux, in which the murders likely wouldn’t have happened if the two hadn’t teamed up.
Other notorious examples of folie à deux include Leonard Lake and Charles Ng (The Hillside Stranglers), Doug Clark and Carol Bundy (The Sunset Strip Killers), and Susan (later “Suzan”) and James (later “Michael”) Carson (The Witch Killers).
Folie à Deux and the Courts
According to Holoyda, the field of psychiatry no longer recognizes a diagnosis of folie à deux.
“In the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), shared psychotic disorder was eliminated,” he says. “There is, however, acknowledgement of a presentation entitled ‘delusional symptoms in the partner of the individual with delusional disorder,’ which can be diagnosed under the ‘other specified schizophrenia spectrum and other psychotic disorder’ category.”
Indeed, under the current DSM-5 definition, it states: “In the context of a relationship, the delusional material from the dominant partner provides content for delusional belief by the individual who may not otherwise entirely meet criteria for delusional disorder.” This makes it difficult for juries to accept a diagnosis of mental illness and for legal teams to establish a solid foundation for an insanity defense.
Given shared psychotic disorder’s removal from DSM-5, says Holoyda “such a defense is likely to diminish in frequency going forward.”