CLAIM:	People with severe mental illness are more likely to be victims rather than perpetrators of serious violence.
FACT:	The evidence is not clear cut.

Being a victim of crime, particularly a violent crime is a serious and frightening matter and deserves to be investigated thoroughly.

There are however relatively few studies of mentally ill victims of crime in Britain – and the conclusions of these studies are contradictory.

Equal numbers of victims and perpetrators

Some of the best studies in Britain of mentally ill victims of crime come from a research trial of 700 psychotic patients (UK 700 group). Two studies in 2003 and 2007 found between 16 to 23% reported being a victim of violence.

However an earlier study of this same group of patients found almost exactly the same number (22%) were also perpetrators of violence.

So whilst 23% of psychotic patients said they were victims of violent crime, 22% were committing violent crime and had physically attacked another person.

The difference is statistically negligible.

A study by Hughes and others in the Lancet in 2012, similarly found high levels of victimisation with around 24% of mentally ill adults had been subjected to violence of any kind – but they also found that ‘Mentally ill people were no more likely to have been physically attacked than non-mentally ill people’

Little evidence mental illness causes patients to be victimised.

And whilst some international studies appear to show high rates for people with mental illness to be victims of violent crime, there is little evidence this is related to their mental illness.

It’s not unusual for people with severe mental illness to live in poorer urban areas, to use street drugs, to be unemployed, and have problems living in settled accommodation. In such an environment people will arguably experience higher levels of violent crime than in the rest of the country – regardless of whether they have mental illness or not.

In these studies there is often no comparison or control for levels of violence experienced by people living in similar areas, with similar problems, but without co-existing severe mental illness.

No corroboration – self reports

Many studies of serious crime committed by the mentally ill can usually rely on a whole raft of police and criminal evidence, court reports and medical notes.

Much of the evidence for the mentally ill being victims of violence comes from personal interview with the patients themselves – the rate of violence experienced is self reported, and there is rarely any external corroboration.

Firmly held paranoid and persecutory thoughts are symptoms of some forms of severe psychosis, so it is not surprising that some members of this patient group may feel victimized regardless of the existing reality.

Without external confirmation it is difficult to assess how accurate some of these claims are.

Evidence on mentally ill homicide victims

A study published this year by the University of Manchester (NCISH) is looked at 1496 victims of confirmed homicides in England and Wales over a three year period between January 1 2003 and December 31 2005.

It found that 90 victims (6%) had been mental health patients.

But it also found that 213 patients (14%) had been convicted of a homicide within the same three year period.

Of the 90 mental health patient victims – 29 had been killed by another patient with mental illness.

A Danish study in 2001 showed apparently high levels for the mentally ill to be at risk of homicide, but provided no information on the perpetrators, living environment, or circumstances of the homicide – nor of the homicide rate for comparable subjects living in the same areas but without mental illness.

 

Conclusions

Whilst mentally ill people undoubtedly do experience high levels of violence, there is currently little robust evidence this is directly related to their illness.

Rigorous studies have shown equal numbers of seriously ill people are both the victims and perpetrators of violence.

The evidence from England and Wales suggests mental health patients are more likely to be perpetrators rather than victims of homicides.

The current evidence base does not support the claim that the mentally ill are more likely to be victims rather than perpetrators of serious violence.

 

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SOURCES

The two studies on mentally ill victims of the UK 700 group are:

Walsh E , Moran P, Scott C, McKenzie K, Burns T, Creed F, Tyrer P, Murray RM and Fahy T. Prevalence of violent victimisation in severe mental illness. British Journal of Psychiatry (2003), 18 3, 233-238

Dean K; Moran P; Fahy T; Tyrer P; Leese M; Creed F; Burns T; Murray R; Walsh E. Predictors of violent victimization amongst those with psychosis. Acta psychiatrica Scandinavica (2007)
116(5):345-53.

The study on perpetrators from the UK 700 group is from

Walsh et al, Reducing violence in severe mental illness: randomised controlled trial of intensive case management compared with standard care BMJ. 2001 November 10; 323(7321): 1093.

Patients as Homiicde Victims in England and Wales

Rodway C, Flynn S, While D, Rahman MS, Kapur N, Appleby L, Shaw J, Patients with mental illness as victims of homicide: a national consecutive case series. Lancet Psychiatry. 2014;1(2):129-134.

Danish homicide study

Urara Hiroeh, Louis Appleby Preben Bo Mortensen Graham Dunn. Death by homicide, suicide, and other unnatural causes in people with mental illness: a population-based study The Lancet, Volume 358, Issue 9299, Pages 2110 – 2112, 22 December 2001

 

The mental health charity MIND conducted a survey in 1996 (Not Just Sticks and Stones) which found 14% of respondents said they had been physically assaulted. It was unclear whether this was as a direct result of their mental illness or because of other social and demographic factors. It was based on self reporting and contained no control group. Its accuracy and evidential value therefore is arguably questionable.