Today, I came across a post on why the new DSM-5 definition of autism may actually be good. In it, the author talked about an apparent mass murder and the associated speculation of the killer having Asperger’s Syndrome. I googled, hoping to find out which mass murder she was writing about, but instead came across a Washington Post article which claimed a “significant” link beteeen mass murder and autism. I read the original study (Allely et al., 2014) on which this article was based, and I’m not impressed.
First, the actual question the authors aim to answer, is inverted. They research whether a significant number of mass or serial killers have autism and/or head injury. They found that this is so: roughly ten percent of the mass or serial killers the researchers read about, had suspected or diagnosed ASD, and a similar percentage had a possible or definite head injury. This may be significantly more than the prevalence of autism or head injury in the general population, but so what? The really important question is whether autistics or those who sustained head trauma are more likely to become serial killers. One thing I learned from Ton Dekrsen, author of Lucia de B., a book on the Dutch nurse falsely accused of serial murder on her patients, is that a statistical link that runs in one direction, doesn’t necessarily run in the other as well. Since serial or mass murders are rare, this is especially important.
Also please note that Allely et al. state that, of none of the six murderers (out of 239 total!) with “definite” autism, diagnostic data was available. “Probable” ASD also included a psychiatrist or psychologist having said the murderer had ASD. This raises suspicion, as psychologists and psychiatrists are not immune to media hyping wanting to label every murderer with the mental illness du jour. Dutch readers might remember psychiatrist Menno Oosterhoff accusing Volkert van der Graaf, who murdered politician Pim Fortuyn, of having Asperger’s in 2003. With no diagnostic data on any of the murderers with suspected or “definite” ASD, it is really speculative to even say that there is a one-directional link between mass murder and ASD. And don’t get me talking on the “possible” ASD people, who were simply described as “odd” or “loners” by their family members.
Allely et al. do say in their discussion that speculation about a link between autism and mass murder may lead to negative steretoypes. This of course is not a reason not to document it. If autistics are in fact more likely to be serial or mass murderers, there’s no reason not to write that into a research paper. The thing is, due to the rarity of serial and mass murders, this is unlikely to ever become truly apparent. And even if a definite link could be found, so what? I recently read in another book that, while there is a link between schizophrenia and violence, locking away all schizophrenics in England and Wales for the rest of their lives would save the lives of four potential murder victims each year.
Allely CS, Minnis H, Thompson L, Wilson P, and Gillberg C (2014), Neurodevelopmental and Psychosocial Risk Factors in Serial Killers and Mass Murderers. Aggression and Violent Behavior, 19(3)288-301. DOI: 10.1016/j.avb.2014.04.004.