Autism, Asperger’s Syndrome, Crime, and Violence

Image Courtesy of Stuart Miles, FreeDigitalPhotos.net
Image Courtesy of Stuart Miles, FreeDigitalPhotos.net

Are people with autism or Asperger’s syndrome more likely to commit acts of violence or other crimes?  Over the years, many studies have been conducted to explore this question, and the collective evidence from this research indicates that people with autistic spectrum disorders (ASDs) are no more likely (and perhaps even less likely) than neurotypicals to commit violent crimes.

Many people assume that those on the autistic spectrum are more likely to commit crimes for a number of reasons:

    • They have a limited understanding of social rules, so they may misread social signals (for example, a person with Asperger’s syndrome might believe that someone wants to be friends or fail to notice when he is frightening another person, which can lead to charges of stalking).
    • They often have poor emotional and impulse control, which can lead to distressing outbursts.
    • They are usually naïve, and therefore vulnerable to exploitation by unscrupulous people, so they can be manipulated into participating in criminal activities.
    • They are often guided by rationality and logic, and it is possible to find logical reasons to commit crimes (on the other hand,  it is easier to find logical reasons to not commit crimes, given the consequences of criminal activity).
    • Special interests are very important to those with ASDs, and it is possible that individuals on the spectrum could develop illegal special interests (however, the findings of various studies suggest that this is very uncommon).

On the other hand, there are compelling reasons why those with ASDs would avoid committing crimes:

    • People on the spectrum are inclined to adhere rigidly to rules, including rules of law.
    • Despite the persistent myth that people on the spectrum lack empathy, research has found that those with ASDs actually suffer from too much empathy rather than too little. They fail to respond to those in distress because they are overwhelmed with emotion or lack the social understanding to react appropriately, not because they are indifferent to the suffering of others.
    • People who abuse drugs are more likely to behave violently and commit crimes, and drug use is far less common among those with ASDs than neurotypicals (Merritt, 2009).

Autistic Spectrum Disorders, Crime, and Violence: Research Findings

Evidence regarding violence and criminal convictions suggests that overall rates for most types of serious crime are similar or lower for those on the autistic spectrum:

    • Ghaziuddin et al. (1991), who conducted a review of 132 studies, found that the rate of violence among those with Asperger’s syndrome was just over 2%, compared to approximately 6% to 7% for the general U.S. population.
    • Hare et al. (2000), in a psychiatric hospital population study, found that those with ASDs were less likely to have committed sexual offenses than neurotypicals, equally likely to have committed murder, and more likely to have set fires.
    • Murphy (2003) found that people with Asperger’s syndrome in a psychiatric hospital received lower scores on a violent behaviour index than those with schizophrenia or personality disorders, and were less likely to abuse drugs and alcohol.
    • Woodbury-Smith et al. (2006) found that high-functioning individuals with ASDs had significantly lower rates of criminal offending than neurotypicals in the UK. The only type of crime for which offense rates were higher was criminal damage to property. Some study participants did report having been violent in the past. However, this study was quite small, including only 25 individuals with ASDs and 20 neurotypicals in the comparison group, so more research is needed to draw conclusions.
    • Elvish (2007) found that those with ASDs are less likely than neurotypicals to commit sexual offenses against children.
    • Mouridsen et al.’s (2007) study of Danish offenders found that rates of conviction for people with Asperger’s syndrome were similar to those of neurotypicals. However, those on the spectrum were more likely to commit acts of arson.
    • Murphy (2007) conducted an assessment of patients at Broadmoor Hospital in the UK, finding that none of those with Asperger’s syndrome met the criteria for psychopathy, a personality disorder characterized by lack of empathy, a tendency to use people, and increased likelihood of committing crimes.
    • Dein and Woodbury-Smith (2010), after conducting a research review, concluded that those with Asperger’s syndrome are less likely than neurotypicals to commit acts of violence or sexual offenses, but more likely to set fires and commit fraud.
    • Cheely et al. (2012), in a study of juvenile crimes, found that juvenile offenders who were diagnosed with ASDs were more likely to have committed crimes against people and less likely to have committed property crimes. However, most of the crimes against people occurred at school, where autistic students face not only severe environmental stressors, but also bullying in many cases, which can cause them to lash out defensively. This is probably the reason why this study found a higher rate of aggression among kids with ASDs, whereas studies of adults have typically found similar or lower rates of violent crime in the ASD population.
    • Lerner et al. (2012) found that people with high-functioning ASDs are no more likely than neurotypicals  to commit violent crimes.
    • King and Murphy (2015), after conducting an extensive review of studies, found that people with ASDs are not over-represented in the criminal justice system, and those who have been convicted of crimes are less likely to violate their probation, most likely because they are inclined to follow clearly specified rules.

Autistic Spectrum Disorders and the Criminal Justice System

People with ASDs may be wrongfully branded as criminals because they become confused during investigations. They do not function well in unfamiliar environments, and they may not understand the social rules associated with legal procedures. Moreover, they may be too trusting of their questioners, and they can misinterpret police statements or naively disclose personal fantasies when questioned (Allen et al., 2007). Also, during questioning or other legal proceedings, those with ASDs may display seemingly inappropriate emotional responses or tones of voice, which could lead to false assumptions about guilt or lack of remorse (Taylor et al., 2009). All of these tendencies make people with ASDs vulnerable to wrongful accusations and convictions.

Overall, the evidence suggests that those with ASDs are not more inclined than neurotypicals to commit violent crimes, and actually less likely to commit sexual crimes. Moreover, when those with ASDs do commit crimes, they usually do so because they have failed to understand other peoples’ points of view rather than because they wanted to cause harm, or because they lashed out in response to bullying. Those with ASDs are actually far more likely to be victims of crime than perpetrators due to their naiveté and lack of social understanding.

Note: Asperger’s syndrome has been removed from the DSM as a diagnostic category, and is now considered part of the larger autistic spectrum. However, many people still use and identify with the term, and it has been an area of focus for prior studies, so we continue to use Asperger’s syndrome in this article series. 

For more articles on ASDs, see the main Autism and Asperger’s Syndrome page.

References

    • Allen, D., Evans, C., Hider, A., Hawkins, S., Peckett, H., & Morgan, H. (2008). Offending behaviour in adults with Asperger syndrome. Journal Of Autism and Developmental Disorders, 38(4), 748-758.
    • Cheely, C.A., Carpenter, L.A., Letourneau, E.J., Nicholas, J.S., Charles, J. & King, L.B. (2012). The prevalence of youth with autism spectrum disorders in the criminal justice system. Journal of Autism and Developmental Disorders, 42(9), 1856-62.
    • Dein, K., & Woodbury-Smith, M. (2010). Asperger syndrome and criminal behaviour. Advances in Psychiatric Treatment, 16(1), 37-43.
    • Elvish, J. (2007). The exploration of autistic spectrum disorder characteristics in individuals within a secure service for people with learning disabilities. Thesis for Doctorate in Clinical Psychology, The Tizard Centre, University of Kent.
    • Ghaziuddin, M., Tsai, L., & Ghaziuddin, N. (1991). Brief report: violence in Asperger syndrome, a critique. Journal of Autism and Developmental Disorders, 21(3), 349-354.
    • Hare, D. J., Gould, J., Mills, R., & Wing, L. (2000). A preliminary study of individuals with autistic spectrum disorders in three special hospitals in England. National Autistic Society.
    • Katz, N., & Zemishlany, Z. (2005). Criminal responsibility in Asperger’s syndrome. The Israel Journal of Psychiatry and Related Sciences, 43(3), 166-173.
    • King, C., & Murphy, G. H. (2014). A systematic review of people with autism spectrum disorder and the criminal justice system. Journal of Autism and Developmental Disorders, 44(11), 2717-2733.
    • Lerner, M. D., Haque, O. S., Northrup, E. C., Lawer, L., & Bursztajn, H. J. (2012). Emerging perspectives on adolescents and young adults with high-functioning autism spectrum disorders, violence, and criminal law. Journal of the American Academy of Psychiatry and the Law Online, 40(2), 177-190.
    • Merritt, T. A. (2009). Drug use and abuse by people with autism. Honors Thesis, Western Michigan University.
    • Mouridsen, S. E., Rich, B., Isager, T., & Nedergaard, N. J. (2007). Pervasive developmental disorders and criminal behaviour: A case control study. International Journal of Offender Therapy and Comparative Criminology, 52, 196-205.
    • Murphy, D. (2003). Admission and cognitive details of male patients diagnosed with Asperger’s syndrome detained in a special hospital: Comparison with a schizophrenia and personality disorder sample. The Journal of Forensic Psychiatry, 14(3), 506-524.
    • Murphy, D. (2007). Hare Psychopathy Checklist Revised profiles of male patients with Asperger’s syndrome detained in high security psychiatric care. The Journal of Forensic Psychiatry & Psychology, 18(1), 120-126.
    • Sarris, M. (2014). What Do We Really Know About Autism and Crime? Interactive Autism Network.
    • Taylor, K., Mesibov, G., & Debbaudt, D. (2009). Asperger Syndrome in the Criminal Justice System (By Judge Kimberly Taylor (retired), Dr. Gary Mesibov, and Dennis Debbaudt (2009), Modified and Reformatted for an AS Population by Nomi Kaim). Asperger/Autism Network.
    • Woodbury-Smith, M. R., Clare, I. C. H., Holland, A. J., & Kearns, A. (2006). High functioning autistic spectrum disorders, offending and other law-breaking: findings from a community sample. The Journal of Forensic Psychiatry & Psychology, 17(1), 108-120.