Severe mental illness and dangerousness-part 1
For decades clinicians and academics have argued and published works that claim that people with severe mental illnesses are no more dangerous than other members of the public. Whereas this is largely true it fails to account for the small number of people with severe mental illness who go on to commit homicide or severely injure people.
This is not surprising given those in the healthcare sector are charged with managing and curing illness and find it difficult to accept failure. Therefore, their perceptions are biased towards the population level data that suggests risk is low.
A recent study seems to follow this pattern in focusing on population level data. At that level people with serious mental illness are more than ten times more likely to be victims of violent crime than perpetrators of it.
At a population level this argument is of course sound, however it has helped to mask proper examination of the minority of people with severe mental disorders who become dangerous.
These cases have been attracting sporadic attention over the decades when an incident captures the public’s attention such as the Campbell (1984) Clunis (1992) Silcock (1992) and the more recent Calocane case (2023).
Severe mental illness does however raise the statistical risk of violent behaviour, but the numbers are far smaller than suggested, and thus consideration of the specific factors at play matter. Population-level research tracking violent crime found that serious psychiatric disorders account for a limited fraction of overall violence in society. Most violence is committed by people without any formal mental illness diagnosis.
Thankfully this is now changing, and several researchers have begun to drill down in order to more fully understand severe mental illness and dangerousness, more importantly how to spot it and intervene to attempt to prevent tragedy.
When violence does occur in the context of mental illness, some factors appear consistently; untreated psychosis raises risk as does substance use combined with severe mental illness. Neither schizophrenia on its own nor substance use alone reliably predicts violence, but when they occur together in an untreated person, the risk profile shifts dramatically. Often the telltale signs are missed by the healthcare professionals who are responsible for the person’s mental healthcare. In addition, inquiries after a tragedy has occurred, have suggested that the views of family and friends are often given little weighting when assessing risk.
The National Institute of Mental Health’s (NIMH) Epidemiological Catchment Area (ECA) study was the first community-based study that examined this issue. The ECA study concluded that people with serious mental illness, mainly schizophrenia, bipolar disorder and major depressive disorder were two to three times more violent than those without such illnesses. “Lifetime violence among individuals with serious mental illness was 16% compared with 7% among individuals without mental illness. The risk of violence in the seriously mentally ill increased to 43% with co-morbid substance abuse.”
Hundredfamilies.org, set up by families of victims of homicides committed by mentally ill individuals, state that “Although Mental health problems are common in Britain and the majority of mental health patients are never violent, Mental Health Services remain the most violent sector of the NHS. 70% of all physical assaults in the NHS take place in mental health and learning disability services. One in five mental health staff report being assaulted, the highest rate for any sector within the NHS, including A&E.”
They go on to state:
“In Britain official figures show that on average there are more than 120 victims of killings by people with mental illness every year.”
So, although at population level the risk is low there are a significant number of cases where life is unnecessarily lost due to untreated, poorly managed, mentally ill people.
In the next article approaches to severe mental illness that might close the gap between risk and outcome is discussed.
Sources:
1-https://neurolaunch.com/dangerous-psychological-disorders/
2-https://pmc.ncbi.nlm.nih.gov/articles/PMC6179640/
