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Mental Illness Does Not Equal Dangerous, Mostly

Understanding the mix of features that can lead to crime

Last spring, I was with my children and four more in a nearby village where I often write in a local café. A small, older man who is friendly, has an impressive vocabulary, walks fast, keeps moving, avoids eye contact, speaks with clipped, broken statements and an illogical flow of ideas is a familiar figure in the town. The café staff will ask him what he wants and hand him a coffee or a meal. He chats with/at people on the bench outside, spews encouragements for high grades and hard work, gives emphatic tips on your baseball swing with gestures, jumps up and then walks away while continuing the conversation or rather the monologue which is sort of about you and sort of not. He excitedly advises you even if you never shared anything, as if he wants to give you something. The kids were taken aback. I explained that I had seen him here for years and he is beloved in his own way by the locals. They chatted with him briefly as he bee-lined back to us, and then right past continuing his commentary.

Most mentally ill people are not dangerous. And yet public perception lags miles behind this reality. A recent Kenneth Cole billboard drew fierce criticism for stating, “Over 40M Americans suffer from mental illness. Some can access care… All can access guns." In fact, only 3-5% of firearm assaults are linked to people with serious mental illness and those with mental illness are more likely than others to be the victim of a crime, as the American Psychiatric Association quickly pointed out.

Yet high profile crimes, such as the on-air Virginia shooting in August of two young reporters, Alison Parker and Adam Ward by former colleague, Vester Flanagan, continue to inflame and confuse the public as to just how dangerous the mentally ill are.

Mental illness means many different things. While one cannot diagnose without in person examination, it appears that entitlement, rage, job loss, paranoia and vengeance were at play in this case. A few personality traits, such as lack of conscience and entitlement combined with a very specific kind of psychosis are a set up for violent crime. A severe stressor can act as a trigger. Knowing the risk factors and the dangerous mixes can help us anticipate and protect.

Six clarifications about mental illness and violence:

  1. Mental illness is not one thing, but many varied conditions. People cannot be grouped into one category.
  2. Mental Illness is not synonymous with dangerous and most mentally ill people are not dangerous.
  3. People with mental illness differ in demeanor, biology, and presentation. Different people manifest the same disease in varying ways to greater or lesser degrees. There are often have overlaps and mixes of conditions. No one fits a strict formula.
  4. Mental organization is necessary to plot crimes so severely psychotic people are usually too impaired to do so. Impulsive crimes are a different matter.
  5. The DSM (Diagnostic and Statistical Manual of Psychiatric Disorders), until the most recent version, made a distinction between mental illness and personality disorders: Axis I for M.I. Axis II For P.D. We now know that much of personality is based on biology, as are many mental illnesses, so there are no longer separate axes. Whether we categorize them as mental illnesses or not, personality disorders are considered a risk factor for violence, while general mental illness (with the exception of certain delusional states and substance abuse) disorders) is not.
  6. Risk factors for violent behavior from an article on mental illness and violence in the Harvard Mental Health Letter include:
  • Violence history
  • Substance abuse
  • Command hallucinations or paranoid delusions
    by Chloe Barron
    Source: by Chloe Barron
    by Chloe Barron
    Source: by Chloe Barron
  • Youth
  • Being male
  • Personality disorders
  • Personal crises
  • Social stress such as poverty
  • Early exposure to violent acts
by Chloe Barron
Source: by Chloe Barron
by Chloe Barron
Source: by Chloe Barron

A couple things about each of these risk factors:

History of violence:

This is similar to history of suicidal attempts, which is the greatest risk factor for suicide. If you have crossed that boundary once, it is easier to do it again.

Substance abuse:

If you are under the influence of a drug, your biology is altered and you might do uncharacteristic things. Some substances such as PCP stimulate violence. This New York Times piece by Bernard Horn, advisor to the Public Leadership Institute, elucidates the link between substance abuse and violence.

Command hallucinations/ paranoid delusions:

Many hallucinations and delusions, though classified as psychotic, are not paranoid in nature and do not involve violent commands. Command hallucinations can, but do not necessarily, involve inner voices that tell you to cause harm. Paranoid delusions include justice-seeking drives that could but not necessarily, lead to aggressive actions. Most people who suffer from psychosis are not harmful to others, but they may be harmful to themselves because when reality testing is poor, judgment fails. You might think you can fly for example and jump off of a building.


Adolescents have a sense of immortality and an unrealistic sense of safety, so they take more risks. Because hormones are pulsing and the brain has not yet matured, they may be more susceptible to impulses, peer pressure, substance abuse temptations and dis-inhibitions which can lead to violent or dangerous acts.

Being male

There is a link between increased levels of testosterone and violence. There is also a link between decreased cerebrospinal fluid 5-HIAA, a metabolite of serotonin in violent criminals. Serotonin influences mood and social behavior. About 90% of those in jail are male. Thus, if you are male with excess testosterone and decreased serotonin you are more at risk.

Personality disorders

The Cluster B Personality Disorders such as anti-social, borderline, narcissism and histrionic can involve poor impulse control, lack of conscience, brief psychotic episodes, egocentricity or entitlement. People who are unable to comprehend or care about the needs of others or are unfazed by legal or moral laws are more at prone to commit violent or vile acts.

Let’s surmise about the aforementioned case for the sake of seeing how traits intersect and inflame each other. The fact that the perpetrator employed social media in his heinous act speaks to vanity and grandiosity (character/ personality disorder issue) as well as vengeful insanity (paranoid/ psychotic issue) and a version of “I’ll show you who I am and what I am made of, how dare you fire me,” (stress, humiliation after job loss issue) However, this is a gross simplification. Many inner forces, fantasies and impulses identified and unidentified can be operating and interacting. While there is much yet to ascertain about brain and behavior and we can never grasp every aspect of another person, we can at least try to untangle the elements and anticipate.

Personal Crises:

Being fired is a trauma. A loss of income or identity, feeling devalued, rejected or humiliated and no longer having a purpose and a sense of place can have a monumental psychological impact. Other crises such as divorce, illness or betrayal can blindside or crush. People have varying degrees of resilience. Some people are extremely sensitive to “narcissistic injury,” – they are gripped by humiliation or shame in the face of a perceived failure. Others can summon stamina, self-esteem, grit and a mindset that allows them to pick up pieces.

Poverty or Social Stress;

People get desperate. This is painfully depicted in the classic Vittorio De Sica film The Bicycle Thief where an impoverished man who must support his family finally saves enough to get a bicycle so he can get a job. The bike is stolen right away. In a desperate moment, he sees an unlocked bike, hesitates, grabs it, flees and is caught. One more hardship can put someone over edge. It can be unbearable to come far after great effort and fall in an instant.

Early exposure:

If a behavior is very familiar to you are more likely to adopt it. Modeling may be a conscious or unconscious process. One version of this is identification with the aggressor wherein victim turns to perpetrator to mitigate pain and increase a sense of control. Passivity transformed into action is often a positive but can sometimes lead to disaster.

Understanding the interplay of mood and personality disorders, disposition, stressors and capacity for resilience can help us get a better rein on seemingly random acts.

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