Dangerous by Default? The Harmful Myth That People with Mental Illness Are Criminals

Abstract

The stereotype that people with mental health disorders are inherently dangerous drives fear, bad policy, and worse outcomes. Research shows: (1) most violence is not caused by mental illness; (2) people living with serious mental illness (SMI) are far more likely to be victims of violence than perpetrators; and (3) structural stigma channels psychiatric crises into police and jails, reinforcing the myth. The fix is not more criminalization, but better care, crisis alternatives, and accurate communication.

What the evidence actually shows

Most violence is not attributable to mental illness.

High-quality epidemiology finds that serious mental illness alone accounts for only a small fraction of interpersonal violence at the population level. In a widely cited synthesis and related work, the population-attributable risk of violence from SMI alone was roughly 4%, meaning ~96% of violence would still occur if SMI vanished tomorrow. Risk of violent behavior is far more tightly linked to factors like substance misuse, prior violence, youth, and social stressors than to diagnosis per se (Swanson et al., 2015).

People with mental illness are more often victims than perpetrators

A landmark community study found adults with SMI had a >11-fold higher rate of violent victimization than the general population; later reviews confirm elevated victimization risk across settings. In other words, the typical person with SMI is at risk from others, not the other way around (Teplin et al., 2005).

Yes, some diagnoses show elevated relative risk—but context explains most of it.

A modern review notes adjusted relative risks of ~2–4 for violent outcomes across several psychiatric disorders compared to people without diagnoses, yet emphasizes the crucial role of co-occurring substance use and social adversity—the variables that actually drive most risk and are targetable for prevention (Whiting et al., 2021).

Why the “criminal by default” myth persists

1) Salient news, rare events.

News coverage over-associates mental illness with violence (especially gun and family violence) and under-reports recovery; a content analysis of 400 stories (1995–2014) found violence was the dominant frame (55%), whereas only 14% described successful treatment. Media narratives shape public fear, policy, and even clinical judgment (McGinty et al., 2016).

2) Structural stigma and criminalization.

Where crisis services are thin, police and jails become default “first responders.” Federal statistics show a substantial share of incarcerated people report mental health problems, illustrating how unmet needs are shifted into carceral systems—settings ill-suited to treatment and prone to poor outcomes (Maruschak et al., 2021).

3) Diagnostic overshadowing in general medicine.

Physical complaints from psychiatric patients are too often dismissed as “just the mental illness,” delaying care for heart disease, infection, and other conditions. Recent concept analyses and reviews describe this diagnostic overshadowing as a key mechanism of health harm and earlier mortality (Hallyburton, 2022).

4) Everyday language.

Labels like “the mentally ill” feed essentialism. The 2022 Lancet Commission documents how public, self-, and structural stigma degrade health and access to care—and offers concrete anti-stigma actions (Thornicroft et al., 2022).

What actually reduces crime and harm (hint: it’s care, not blame)

Build civilian crisis responses.A robust continuum—24/7 crisis lines (988), mobile crisis teams, and crisis receiving centers—diverts emergencies away from police/jail and toward treatment. SAMHSA sets out national guidance and reports rapid scaling since 988 launched in 2022.

Treat co-occurring substance use and reduce social stressors.

Because substance misuse and destabilizing life events mediate much of the violence risk, investment in integrated SUD treatment, supportive housing, and employment should be a public-safety priority. Large epidemiologic work shows these factors—not diagnosis alone—explain most variance in risk (Elbogen & Johnson, 2009).

Use evidence-based community care.

Models like Assertive Community Treatment (ACT) or adaptations that explicitly address justice involvement can reduce crises and custodial days when implemented well, especially alongside housing and benefits coordination. (Evidence is mixed when programs are narrowly hospital-reduction focused; newer forensic-adapted ACT designs show more promise for reducing detention) (Cuddeback et al., 2008).

Fix healthcare bias to prevent avoidable deaths.

Health systems should audit for parity in screening (e.g., cardiovascular risk) and deploy checklists to prevent overshadowing during ED and primary-care encounters—concrete steps recommended in recent diagnostic-inequality reviews (Liberati et al., 2025).

Change how we talk and report.

Media guidelines urge reporters not to imply that mental illness routinely causes violence and to include help resources and prevalence context; trauma-informed reporting reduces fear without minimizing real risks.

A quick myth-to-fact translation you can use

• Myth: “Most violent crimes are due to mental illness.”

  
  

  Fact: Only a small share (~4%) of violence is attributable to SMI alone; most violence stems from substance misuse, prior violence, and situational stressors (Swanson et al., 2015).

• Myth: “People with mental illness are dangerous.”

  
  

  Fact: They are disproportionately victims of violence; prevention means stabilizing housing, income, relationships, and access to care (Teplin et al., 2005).

• Myth: “Jail is where care finally happens.”

  
  

  Fact: Carceral settings concentrate unmet need and perform poorly on treatment. Building 988 + mobile crisis + crisis centers keeps people—and communities—safer.

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Conclusion

Equating mental illness with criminality is not just inaccurate; it’s harmful public health. It deters help-seeking, degrades medical care through bias, and justifies channeling treatable crises into jails. The evidence points to a different map: expand civilian crisis care, treat co-occurring substance use, reduce social stressors, and report responsibly. When we replace stigma with systems that work, communities become safer and people live longer, healthier lives (Thornicroft et al., 2022).

References

• Cuddeback, G. S., Morrissey, J. P., & Cusack, K. J. (2008). How many forensic assertive community treatment teams do we need? Psychiatr Serv, 59(2), 205-208.

• Elbogen, E. B., & Johnson, S. C. (2009). The Intricate Link Between Violence and Mental Disorder: Results From the National Epidemiologic Survey on Alcohol and Related Conditions. Archives of General Psychiatry, 66(2), 152-161.

• Hallyburton, A. (2022). Diagnostic overshadowing: An evolutionary concept analysis on the misattribution of physical symptoms to pre-existing psychological illnesses. Int J Ment Health Nurs, 31(6), 1360-1372.

• Liberati, E., Kelly, S., Price, A., Richards, N., Gibson, J., Olsson, A., Watkins, S., Smith, E., Cole, S., Kuhn, I., & Martin, G. (2025). Diagnostic inequalities relating to physical healthcare among people with mental health conditions: a systematic review. eClinicalMedicine, 80, 103026.

• Maruschak, L. M., Bronson., J., & Alper, M. (2021). Indicators of Mental Health Problems Reported by Prisoners: Survey of Prison Inmates, 2016 (Bureau of Justice Statistics, Issue. J. S. B. Justice Department.

• McGinty, E. E., Kennedy-Hendricks, A., Choksy, S., & Barry, C. L. (2016). Trends In News Media Coverage Of Mental Illness In The United States: 1995-2014. Health Aff (Millwood), 35(6), 1121-1129.

• Swanson, J. W., McGinty, E. E., Fazel, S., & Mays, V. M. (2015). Mental illness and reduction of gun violence and suicide: bringing epidemiologic research to policy. Annals of Epidemiology, 25(5), 366-376.

• Teplin, L. A., McClelland, G. M., Abram, K. M., & Weiner, D. A. (2005). Crime victimization in adults with severe mental illness: comparison with the National Crime Victimization Survey. Arch Gen Psychiatry, 62(8), 911-921.

• Thornicroft, G., Sunkel, C., Alikhon Aliev, A., Baker, S., Brohan, E., El Chammay, R., Davies, K., Demissie, M., Duncan, J., Fekadu, W., Gronholm, P. C., Guerrero, Z., Gurung, D., Habtamu, K., Hanlon, C., Heim, E., Henderson, C., Hijazi, Z., Hoffman, C.,…Winkler, P. (2022). The Lancet Commission on ending stigma and discrimination in mental health. Lancet, 400(10361), 1438-1480.

• Whiting, D., Lichtenstein, P., & Fazel, S. (2021). Violence and mental disorders: a structured review of associations by individual diagnoses, risk factors, and risk assessment. Lancet Psychiatry, 8(2), 150-161.