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Mass Shooting and the Myth of the Violent Mentally Ill

Are mass shooters always mentally ill? We should not assume that they are.

When the latest school shooting took place a few days ago at the Marjory Stoneman Douglas High School in Parkland, Florida, President Trump tweeted:

“So many signs that the Florida shooter was mentally disturbed, even expelled from school for bad and erratic behaviour. Neighbours and classmates knew he was a big problem. Must always report such instances to authorities, again and again!”

With declarations such as these, President Trump and a number of his colleagues made school shootings a question largely about mental health, implying that the cause of such actions is that the people carrying them out are mentally ill. In doing so they help perpetuate the stereotype that mentally ill individuals are violent and dangerous, and thus reinforce stigmatising beliefs about mental illness that, though common, are unfair and erroneous.

Associating mental illness with violence is, in a certain respect, a natural reaction to an action that to most people seems unfathomable. It is natural in the sense that in trying to understand mass shootings—and to find something to blame them on—especially when they involve children, one immediately asks who would do such a thing and a common answer is that nobody who thinks like us, like most people, would. In this, purely statistical sense, a person who acts in this way is abnormal.

One could then take the further step and associate this behavior to other kinds of behavior that is often incomprehensible to the unaccustomed eye and which is associated with mental illness—such as behavior exhibited by depressed individuals or by people suffering from anxiety, psychosis, obsessions, and compulsions. Though mental illness is not necessarily accompanied by strange behavior (and exhibiting strange and abnormal behavior does not mean you have a mental illness), the belief that it is is held by many people and so the connection is easy to make. So one way the association between mental illness with extreme violent behavior can be made is by associating it first with incomprehensible behavior, and then connecting it with other behavior we experience as incomprehensible. Another way to make the association could be by saying that only someone who is “sick” could do such a thing—and the sickness in this case would not be associated with heart disease or diabetes, but with sickness of the mind.

However the link may be made, and however easy it may be to be led to make this link, this association is not only not supported by empirical evidence, but it is also counterproductive—both when it comes to addressing mental illness, and to addressing mass shootings and gun violence in general.

This is not to deny that some mass shooters are mentally ill. Some are. Just as some (most) mass shooters are not mentally ill. In either case though, generalizing to the whole population (that of the mentally ill or to the not mentally ill) is unfair and not supported by evidence.

There is substantial research that shows that the correlation between mental illness and violence is much lower than is commonly assumed and that mass shooters are not in their majority mentally ill. Even in cases of severe mental illness, like schizophrenia, research shows that there is no significant link between mental illness and mass shootings or other forms of extreme violence. In fact, the evidence shows that the percentage of mentally ill people that are violent is less than the percentage of violent people in non-mentally ill populations. For instance, data shows that, at most, only around 5 percent of crimes in the U.S. are performed by people with mental illness and that the percentage is the same for violent crimes—which means that 95 percent of violent crimes are committed by non-mentally ill individuals.

And, of course, most mental illness is not correlated with violence at all. There is no link between violence and most mental disorders like, for instance, ADHD, Asperger’s, anxiety disorders, OCD, anorexia or bulimia nervosa.

People living with such disorders, just like people with mental disorders of any kind, are no more violent than people who do not have these conditions. So associating violence with mental illness stigmatizes a whole group of people unfairly.

Though mental illness of any kind in itself is not predictive of violence, a tendency towards extreme violent behavior is associated with other risk factors including various environmental stressors, past trauma (e.g., physical abuse), substance abuse, domestic violence, a history of incarceration, parental criminal history and access to firearms. For example, there is substantial evidence that people with mental illness who do end up committing violent crimes (just as people who are not mentally ill but commit violent crimes) are also substance users, a factor which is a more reliable indication of violent behavior than the presence of mental illness.

It is factors such as these that, regardless of mental health, are predictive of violent tendencies and violent behavior. Ignoring such determinants of violence boils down to a form of scapegoating—trying to easily make sense of mass shootings by blaming them on mental illness while ignoring scientific research that shows that this phenomenon is much more complicated than that and that addressing it effectively will have to involve focusing on other factors, including sociocultural ones.

I have written in a past blog post about the effects that stigma has on mental illness and how it affects the quality of life and the recovery prospects of people living with mental disorders. I argued there that perpetuating wrong stereotypes about mental health is a public health issue but it is also a question of social justice. This is also the case when it comes to blaming mental illness for mass shootings.

One effect that this stigmatization can have on people with mental illness is that they will avoid seeking treatment in order not to be labeled as dangerous. Clearly, this is a form of harm towards innocent people, since it compromises their recovery prospects and thus their quality of life. But this also means that potentially dangerous people—people with violent tendencies—will also not seek therapy since, they too, will not want to be labeled as mentally ill and thus carry the stigma that goes with such a label.

In the end, it is misguided to causally connect extreme violence with mental illness and, more importantly, it is unlikely that doing so will have any effect in preventing such incidents from happening again. Instead of taking the easy route of scapegoating we should try to understand and address the various determinants of violence, including sociocultural determinants, and make sure that people with violent tendencies have access to affordable therapy and that, regardless of their mental health, they do not have access to guns.