Are the Mentally Ill Dangerous?

Mental Illness is Common and Costly

  • Nearly 1 out of 5 Americans struggle with mental illness each year, and almost half of all Americans will develop a mental illness in their lifetimes [1].
  • Mental illnesses account for more disability in developed countries than any other group of illnesses, including cancer and heart disease, according to the World Health Organization [2].
  • Mental illness causes tremendous distress but less than half the people suffering with a mental illness in the U.S. get treatment [3].
  • Mental illness costs the U.S. about $300 billion per year, in addition to the high costs of chronic medical disorders that often accompany mental illness including diabetes, obesity, and cardiovascular disease [1].

Are People with Mental Illness Violent?

The widely-held myth:

  • 60% of Americans thought that people with schizophrenia were likely to be violent, and
  • 32% of Americans thought that people with major depression were likely to be violent [4].

The truth:

Most individuals with psychiatric disorders are not violent. 

  • “Only 3%-5% of violent acts can be attributed to individuals living with a serious mental illness. In fact, people with severe mental illnesses are over 10 times more likely to be victims of violent crime than the general population” [3] [5] [6].
  • “…violence by people with mental illness — like aggression in the general population — stems from multiple overlapping factors interacting in complex ways. These include family history, personal stressors (such as divorce or bereavement), and socioeconomic factors (such as poverty and homelessness). Substance abuse is often tightly woven into this fabric, making it hard to tease apart the influence of other less obvious factors” [4].

Promoting Mental Health

  • “Only 44% of adults with diagnosable mental health problems and less than 20% of children and adolescents receive needed treatment” [3].
  • “…adequate treatment of mental illness and substance abuse may help reduce rates of violence” [4].
  • “A climate that respects and protects basic civil, political, economic, social, and cultural rights is fundamental to the promotion of mental health” [2].

Help people with mental illness [3].

  • Reach out and let them know you want to help.
  • Learn and share the facts about mental health, especially when you hear stereotypes.
  • Treat people with mental illness with respect, just as you would anyone else.
  • Refuse to define them by their diagnosis or using words such as “crazy” or other negative labels.

[1] Centers for Disease Control and Prevention. (2013). CDC Report: Mental Illness Surveillance Among U.S. Adults. Retrieved from

[2] World Health Organization. (2004). Promoting mental health. Retrieved from

[3] U.S. Department of Health & Human Services. (2014). Mental Health Myths and Facts. Retrieved from

[4] Harvard Health Publications. (2011). Mental illness and violence. Retrieved from

[5] Metzl, J. M., & MacLeish, K. T. (2015). Mental illness, mass shootings, and the politics of American firearms. American Journal of Public Health, 105(2), 240–249. 

[6] Stuart, H. (2003). Violence and mental illness: An overview. World Psychiatry, 2(2), 121–124.

[7] Steadman, H. J., Mulvey, E. P., Monahan, J., Robbins, P. C., Appelbaum, P. S., Grisso, T., & … Silver, E. (1998). Violence by people discharged from acute psychiatric inpatient facilities and by others in the same neighborhoods. Archives of General Psychiatry, 55(5), 393-401.

[8] Elkington, K. S., Teplin, L. A., Abram, K. M., Jakubowski, J. A., Dulcan, M. K., & Welty, L. J. (2015). Psychiatric disorders and violence: A study of delinquent youth after detention. Journal of the American Academy of Child & Adolescent Psychiatry, 54(4), 302-312.