Photo by kat wilcox from Pexels: https://www.pexels.com/photo/crime-scene-do-not-cross-signage-923681/
WARNING: This post contains discussion of murder.
On the night of February 2, 1933, in Le Mans, France, René Lancelin headed home from a dinner party. René was upset because his wife Léonie and daughter Genevieve were supposed to have joined him at the party, but they had never shown up. He grew suspicious when he found the front door of his house bolted shut, which was unusual, and he went to the police. When the police broke into the house, they discovered the bodies of Léonie and Genevieve. Both women had been horrendously bludgeoned and stabbed to death.
The police then went to the bedroom of the Lancelin family’s maids, sisters Christine and Léa Papin, fearing that the two of them had also been murdered. But inside their room, the sisters were alive, and they were sitting together on their bed, naked and bloody. The sisters immediately confessed to the murders.
27-year-old Christine and 21-year-old Léa were placed in prison, in separate cells. Christine, in particular, grew extremely distressed due to this separation. At trial, their lawyer pleaded on their behalf not guilty by reason of insanity. Although the consulted doctors initially determined that the girls showed no signs of insanity, they reconsidered when it was revealed that the Papin family had a history of mental illness.
The doctors in this case then concluded that the Papin sisters suffered from folie à deux, which in French means “madness between two people.” The condition is also known as shared paranoid disorder, shared or induced delusional disorder, or shared psychosis. This is a psychological syndrome in which delusions and sometimes hallucinations are transmitted from one person (the ‘inducer,’ who already has a psychotic disorder) to another. (In less common cases with more than two people involved, the condition can be called folie à trois, folie à quatre, and so on.) While the exact etiology of the disorder is unknown, two main factors are believed to be stress and social isolation, and the majority of cases involve women.
In order to be diagnosed with folie à deux, the following criteria must be met (Sadock & Sadock, 2007, table 14.3-5):
The individual(s) must develop a delusion or delusional system originally held by someone else with a disorder classified in schizophrenia, schizotypal disorder, persistent delusional disorder, or acute and transient psychotic disorders.
The people concerned must have an unusually close relationship with one another, and be relatively isolated from other people.
The individual(s) must not have held the belief in question before contact with the other person, and must not have suffered from any other disorder classified in schizophrenia, schizotypal disorder, persistent delusional disorder, or acute and transient psychotic disorders in the past.
Under certain classification systems, only the secondary case (i.e. the ‘induced’ person) can receive a diagnosis of folie à deux (Menculini et al., 2020).
It was believed that the Papin sisters had suffered from shared paranoid disorder, which caused them to commit the heinous crime. Despite this diagnosis, the Papin sisters were convicted of the murders of Léonie and Genevieve. Léa, who was believed to have been heavily influenced by her sister, received a ten-year sentence, while Christine, the ‘inducer,’ received a life sentence. Separated from Léa, Christine grew depressed and died in 1937, having starved herself to death. What happened to Léa is less sure: after leaving prison she assumed a new identity, and she either died in 1982 or 2001. Due to its bizarre and grisly nature, this murder case has inspired a number of books, movies, and plays. Bong Joon-ho even cited it as an inspiration for his recent Oscar-winning film “Parasite” (Jung, 2020).
Do you want to learn more about this poorly understood condition? The MeSH term (medical subject heading) is “Shared Paranoid Disorder”. In the DSM-5, the condition is not listed as a separate disorder but is instead classified under “Other Specified Schizophrenia Spectrum and Other Psychotic Disorder” and is described as “delusional symptoms in [the] partner of [an] individual with delusional disorder.” In the International Classification of Diseases (ICD), the condition is referred to as “shared psychotic disorder” and has code F24.
Do you know of another interesting true crime case with medical connections? Email Rachel Brill at rgbrill@gwu.edu.
Works Cited
Diagnostic and statistical manual of mental disorders. 5th ed. American Psychiatric Association; 2013. https://doi.org/10.1176/appi.books.9780890425596
Jung, E. A. Bong Joon Ho on Why He Wanted Parasite to End With a ‘Surefire Kill’. Vulture. January 14, 2020. https://www.vulture.com/article/parasite-ending-explained-by-bong-joon-ho.html
Menculini G, Balducci PM, Moretti P, Tortorella A. “‘Come share my world’ of ‘madness’: a systematic review of clinical, diagnostic and therapeutic aspects of folie à deux.” International Review of Psychiatry. 2020;32(5-6):412-423. doi: 10.1080/09540261.2020.1756754. https://proxygw.wrlc.org/login?url=https://www.tandfonline.com/doi/full/10.1080/09540261.2020.1756754
Sadock BJ, Sadock VA. Kaplan and Sadock’s Synopsis of Psychiatry: Behavioral Sciences, Clinical Psychiatry. 10th ed. Lippincott Williams & Wilkins; 2007.
Shared Psychotic Disorder. ICD 10 Data. Accessed June 30, 2022. https://www.icd10data.com/ICD10CM/Codes/F01-F99/F20-F29/F24-
