Psychotic Delusions Rarely Precede Acts of Violence By People With Mental Illnesses


A very small minority of “high-risk” individuals diagnosed with mental illnesses perform acts of violence repeatedly, and their acts of violence are rarely preceded by psychotic experiences, according to a study in Clinical Psychological Science. The findings contradict assertions of advocates for involuntary treatment like E. Fuller Torrey, wrote the authors.

“Advocates of involuntary treatment (Torrey, 2011) assert that untreated psychosis can lead directly to violence,” wrote the University of California, Berkeley-led research team. “This assertion leverages the conclusion of research reviews in the 1990s, which suggested that ‘it is not simply the presence of mental illness that induces violence, but rather the specific presence of delusions and hallucinations’ (Junginger, 1996, p. 92). For example, a patient with persecutory delusions may preemptively strike out to ‘protect’ herself or himself.”

The authors then discussed a variety of more recent studies that have “drawn the strength of these early conclusions into question,” including one study that found that “adherence to antipsychotic medication did not significantly reduce violent behavior” in violent patients with mental illnesses, apparently because their violent tendencies often began in childhood long before they exhibited any mental illness symptoms.

In an effort to investigate further, the researchers decided to focus specifically on the most violent and high-risk individuals that had been identified in the earlier MacArthur Violence Risk Assessment Study.

They defined violence as “acts of battery that resulted in physical injury, sexual assaults, assaultive acts that involved the use of a weapon, and threats made with a weapon in hand.” They then identified 100 patients in the MacArthur study “who were involved in two or more incidents of violence during the year after hospital discharge.” These represented 9% of the MacArthur sample, but accounted for 50% of all the violent acts. The researchers then analyzed the interview data to determine how often psychotic experiences such as delusions or hallucinations preceded these persons’ acts of violence.

“Of the 305 violent incidents in which high-risk patients were involved, only 11.5% of incidents were preceded by psychosis,” the researchers stated. There was also no evidence that the psychotic experiences in this small percentage of cases were causally related to the acts of violence.

The authors concluded that their findings “suggest that effective treatment of psychosis will have negligible direct effects on violence for most patients and important but partial effects for the remainder.”

Skeem, Jennifer, Patrick Kennealy, John Monahan, Jillian Peterson, and Paul Appelbaum. “Psychosis Uncommonly and Inconsistently Precedes Violence Among High-Risk Individuals.” Clinical Psychological Science, April 24, 2015, 2167702615575879. doi:10.1177/2167702615575879. (Abstract)

Psychosis rarely linked to violent crime, study says (University of California, Berkeley press release on HealthDay, June 12, 2015)


  1. Personally, I experienced my first “psychotic” episode, just two weeks after being put on my first antipsychotic, exactly when the drug was to “kick in.” And I’ll tell you, it was terrorizing. However, it was also very embarrassing, so much so I wouldn’t leave my bedroom for two days, and refused to even allow my beloved children to see me. A “psychosis” is frightening for the person going through it, but it doesn’t make one violent. To the contrary it makes one try to avoid being around other people, so they may work out the internal struggle. At least that was my experience.

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    • That was my experience too, Someone Else.

      Sometimes I had thoughts of harming others that sickened me. I guess that shows I wasn’t about to act on them. Still it made me afraid to be around others and isolate.

      The psychosis came about through the magical wonder drugs known as Haldol and Stellazine.

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      • RachelE,

        My grandmother was allergic to Stelazine, too. Thankfully for her, doctors back then knew enough to take her off a drug, to which she had an allergic reaction. And she was never put on any other psych drugs and lived happily and healthily to the ripe old age of 94.

        I suffered a first ever ‘psychosis’ from a child’s dose of Risperdal, as a grown adult. However, today’s doctors aren’t smart or ethical enough to take people off drugs they suffer a severe allergic reaction to, or what was confessed to be a “Foul up” in my medical records. Instead they massively tranquilize the person with tons of drugs to cover up an adverse reaction to today’s neuroleptics.

        My initial psychosis seemed like a ‘struggle’ with God, where He supposedly reminded me of all the times He’d protected me. It was terrifying and scary, although not related to me harming others, quite to the contrary. And I did escape the insanity fest that is mainstream psychiatry today, so I believe God is still watching out for me.

        But since your “psychosis came about through the magical wonder drugs known as Haldol and Stellazine,” two neuroleptics, your psychosis was likely due to something known as the central symptoms of neuroleptic induced anticholinergic intoxication syndrome. From

        “neuroleptics … may have additive effects when used in combination. Excessive parasympatholytic effects may result in … the anticholinergic intoxication syndrome … Central symptoms may include memory loss, disorientation, incoherence, hallucinations, psychosis, delirium, hyperactivity, twitching or jerking movements, stereotypy, and seizures.”

        This warning is oddly missing from the interaction checker on your two neuroleptics, but neuroleptics are neuroleptics, so this neuroleptic induced syndrome is likely what caused your psychosis. Feel free to impress your current doctor with your medical acumen by pointing this out, and suggesting to him, that he report this oversight on the site.

        By the way, I found that when checking for interactions between Geodon and Zyprexa, and this warning is missing from a lot of the interactions between various neuroleptics, like Risperdal and Seroquel, too.

        Best wishes in your healing journey.

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  2. “The findings contradict assertions of advocates for involuntary treatment like E. Fuller Torrey, wrote the authors.”
    It’s funny that anyone would take seriously the lies that come from this person’s mouth. “Turn over the furniture” & co guys who can’t wait to force someone down and inject them with poisons.

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