The mass shooting in Oregon by Chris Harper Mercer and his mother's publicly writing about his autism diagnosis have stirred controversy in the autism community as to whether or not his autism was responsible for the mass murder of innocent people. A facebook page was created implying that numerous autistic people were shooters and that autism is associated with violent crime and murder. After a plethora of protests and petitions, Facebook removed the page. In response, there were a flurry of articles published on the internet by a list of authors that reads like a who's who list of some of the most prominent members of the neurodiversity movement, including Michael John Carley, Emily Willingham and the Autistic Self Advocacy Network and Matt Carey of the Left Brain Right Brain blog. The common theme of these articles is that there is no association whatsoever between autism and violence.
Renowned writer Andrew Solomon also weighed in, writing in a new york times article about autism shooters, asking why no one was suggesting diabetes and pattern baldness as causes of mass shootings if they were suggesting autism was one. See Gadfly's answer toward the end of the post.
This is nothing new. The Newgate shootings of Adam Lanza less than three years ago are still fresh in the minds of most people, particularly Lanza's diagnosis of Asperger's. Well-known neurodiversity advocate John Elder Robison was quick to write a response absolving autism for blaming murderous behavior. The IACC, which has had several members of the neurodiversity movement (and zero pro-cure autistics) serving on it since its inception also wrote an article disputing the association between autism and violence after the Lanza shootings.
Aside from the fact that all of these writers advocate neurodiversity, another common denominator in all these pieces is the nearly complete neglect to cite any scientific evidence that there is absolutely no association between autism and violent crime. The trivial exception to that being Carey's citing a study by Ghaziuddin and the studies by Mouridsen in Denmark purporting not to show an association between autism and violence. These were the three publications cited by the IACC's statement on the Sandyhook shooting.
What does the actual literature show? One of the problems of Ghaziuddin's report was that he only did literature reviews of isolated cases and neglected to check court records to ascertain the relationship between autism and violence. This is an old paper nearly twenty-five years old. What do other more recent publications have to say? Only the abstract of Mouridsen's 2012 paper is available online and I have not been able to read the entire paper. One limitation of his 2008 paper is that it only includes convictions and not arrest data such as cases of people on the spectrum that were thrown out for lack of evidence, let alone killers who committed suicide.
Are these writers correct that there is no general association between autism and violent crime, particularly murder? The short answer is probably yes, though it is still questionable (at least to Gadfly) how much is known about the prevalence of violence in autism spectrum disorders.
However, even if there is no clear-cut association between autism and violence and the vast majority of autistic persons are not prone to violence, particularly murder, could there be a subset of those on the spectrum who are predisposed to violence and murder as a result of their brain dysfunction, including co-morbid mental conditions that appear in addition to the symptoms of the ASD? The answer to this question appears to be yes also.
Various case studies have been reported in the literature that gives suggestive evidence (though not specific proof of this). For example Baron-Cohen reported on a 21-year-old man who would take a knife to his 71-year-old girlfriend. Psychiatrist Donna Schwartz-Watts cites three case histories of individuals on the spectrum who committed murder. She concludes their illness was in fact related to their crimes. Newman and Ghaziuddin(author of the original 1991 study concluding there was no relationship between ASD's and crime), in the journal of autism and developmental disorders, stated that there was a relationship between some forms of autism with premorbid psychiatric conditions and certain violent crimes (I have not read this article, but the reports on it).
Psychologist Matt Lerner writes about how theory of mind, impulsivity and other problems may in fact be related to violent crime in some (emphasis added) autistic individuals.
Though the research in this area may have its limitations and not come to any definite conclusions, it would suggest that there is a small subset of persons on the autism spectrum who are predisposed to violent acts, including mass murder. Part of the reason for this may be comorbid psychiatric conditions such as schizoaffective disorder, depression, bipolar, and other things that accompany some of the many forms of autism.
To answer Andrew Solomon's question. Diabetes and pattern baldness are not brain conditions that affect behavior, autism is. There is no comorbidity with mental disorders documented in diabetes and pattern baldness the way there has been in autism. It's another neurodiversity comparison between apples and hurricanes.
The neurodiversity movement often try to separate comorbidity from autism, saying that the seizure disorders that accompany autism are separate from the autism itself. We should just regard this as epilepsy and not part of the individual's autism. Even if the research proves that some mass murderers have a form of autism with comorbidities, they will state that it is these comorbidities that are the culprit and not the autism per se. However, I believe when epilepsy and comorbidities exist they are all a part of one brain disorder with the autism being one symptom. I don't believe you can separate one from another. They are all part and parcel for the course. Therefore, I suspect it is likely that in a small number of cases (though not the vast majority) there is an association between murder and autism. I concede that further research may have to be done to completely validate that conclusion. However, I don't think it is helpful for members of the ND movement and others to claim there is no association whatsoever between autism and murder when at least some scientific evidence would seem to contradict them.