News reports have linked the van attack that killed 10 pedestrians in Toronto this week to the possibility the alleged driver has Asperger’s syndrome, a clinical diagnosis that is currently considered to be part of autism spectrum disorder (ASD).
Alek Minassian, who has been charged with 10 counts of murder and 13 counts of attempted murder, has been described by former classmates and acquaintances as someone with social difficulties and behavioural tics.
It’s not the first time alleged perpetrators of violent acts have been linked to autism.
Autism advocates have been quick to respond — autism does not typically cause violence or motivate an individual to drive a van into pedestrians on a crowded city street.
So what does the science say? Are those with ASD more prone to violence and, if so, what precautions should be taken?
Reduced risk of violence
The straightforward and scientifically supported answer to the question is unequivocally that no, individuals with ASD are not prone to violence any more than any other individual in society.
On the surface, the link may appear to be warranted. There is a belief that, in addition to core social communication and other behavioural difficulties, individuals with ASD also present with limited or non-existent empathy towards others that may lead to a propensity for violence.
But one of the most rigorous studies to date on this topic has shown that, in fact, individuals with ASD are less likely to engage in violent acts.
This study, which examined almost 300,000 individuals in Sweden, explored psychiatric diagnoses, gender, age, and many other variables in the context of violent crime. Overall, 4.4 per cent of individuals with ASD in this large sample were convicted of violent crime in contrast to 2.6 per cent of individuals without ASD. This increased risk of 40 per cent would seem to suggest autism as an influential factor.
However, once co-occurring conditions were accounted for, the rate of violent acts by those with only ASD was less than the group without ASD.
And, importantly, the evidence indicates that having ASD actually reduced the risk of violence.
In essence, it is not having a form of autism that contributes to an individual’s propensity for violent acts; rather, other psychiatric conditions such as conduct disorder and/or adverse childhood experiences appear to be much stronger factors.
Other researchers have investigated this topic and arrived at similar conclusions.
So, what should we take from this? First, journalists should be more aware of their power to influence public perceptions of those with mental health challenges.
They should be clear on what ASD is before asserting that it had any role to play in the atrocities of late.
Second, focusing the narrative around a single potential causal factor for violent acts simplifies what is, inherently, a complex issue. Perpetrators of violence do not commit their acts because of any one single factor. To state that Asperger’s syndrome may cause an individual to behave in this manner is false at best, and very harmful to a large number of individuals.
Third, and most importantly, the public should be better informed about the array of amazing and unique individuals who have ASD.
As almost any individual with autism, their family, or people that support them will tell you, it does not contribute to propensity for violence; however, people with autism are often victims of it.
Researchers and clinicians struggle to provide this information to the public in an effective manner. There are significant efforts to improve society’s understanding of those with ASD — such as World Autism Awareness Day and many local, provincial, and national events to educate society about ASD — many of which have proven to be effective.
We now have to progress towards society’s acceptance of those with autism. This will involve learning about ASD and how we can all work and live together to our mutual benefit, without a climate of fear-mongering or inaccurate information.
If we can achieve that, we will all be better off.
Adam McCrimmon does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.