Violence, mental illness and law enforcement

In past columns dealing with stigma surrounding mental illness, I have discussed the mistaken impression held by many that people with mental disorders are inherently dangerous or violent.

I label this a mistaken impression not because the mentally ill are never violent, but because research has shown people with mental disorders are actually more likely to be victims of assault than perpetrators.

A recent issue of Psychiatric Services featured articles on new research clarifying the relationship between mental illness and violence and examining various ways to prevent it.

One study conducted in 1998 found the link between mental illness and violence is indirect and very often triggered by factors external to illness itself.

Unfortunately, mentally ill individuals are more likely to abuse substances and people who abuse substances are more likely to engage in violent behaviour.

Socioeconomic struggles represent another factor that can lead to violence within this group. Because severe mental illness can be very disabling, patients often have little income and live in poverty in disorganized environments where the probability of violence is higher than average.

When factors such as substance use, poverty and housing were controlled for, this study found mentally ill individuals were no more likely to be violent than people in the general population.

Another paper reviewing 31 US research studies on the topic of violence and mental illness found between two and 13 per cent of mentally ill subjects had committed a violent act while between 20 and 34 per cent reported being a victim of violent crime.

A particularly interesting article assessed the effectiveness of specially trained police officers in deescalating violence when dealing with mentally ill individuals.

This study examined 598 police calls in the Las Vegas area that were dealt with by a specialized crisis intervention team. Officers in this unit receive training to deal with mental health calls and the study sought to determine whether or not this sort of team promotes public safety and diverts ill people from jail to treatment.

Almost 65 per cent of calls involved people with known mental disorders – most common was bipolar disorder followed by depression and schizophrenia. Of those with a known mental illness, 71 per cent were prescribed medication but more than 60 per cent were not taking the medication appropriately.

Individuals with known mental illness were also much more likely to be intoxicated when police arrived at the scene (61 per cent vs. only 38 per cent of those without known mental illness).

Nearly half of all calls were for suicide threats or attempts and another 15 per cent were responding to domestic disturbances.

Although subjects posed a threat to police in 25 per cent of calls, force was only used in six per cent of events. Only two cases resulted in minor injury to the subject, three to minor injury to police and five resulted in injury to someone else.

Almost three quarters of calls resulted in hospitalization and 71 per cent of those hospitalizations were involuntary commitments. Only four per cent of calls resulted in arrest.

Since this was the first study to explore the extent to which specially trained police are able to defuse dangerous crises without force, more research is needed before a decisive conclusion can be reached. However, this study is promising.

Even when faced with potential for violence, the specially trained officers rarely used force, relied on non-lethal measures and did not seriously injure any subjects.

I advocate for any measures that will divert ill individuals from the legal system into appropriate treatment that could help them improve their functioning and life circumstances.


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