Does mental illness make you more likely to kill?

Behind the Headlines

Tuesday October 8 2013

Does being mentally ill make you more likely to kill?

It is unclear how many murders are caused by mental illness

The Sun has run with the front page headline, “1,200 killed by mental health patients,” featuring a story inside entitled “Broken People..Broken System”.

Since publishing its story, the newspaper has been widely criticized for being inaccurate and for stigmatising mentally ill people.

But is there any truth behind the Sun’s headline?


Where did The Sun find its 1,200 deaths figure?

The Sun's 1,200 deaths figure is taken from the 2013 report of the National Confidential Inquiry into Suicide and Homicide by People with Mental Illness. The report, prepared by The University of Manchester, was commissioned by Healthcare Quality Improvement Partnership on behalf of the NHS and government bodies across the UK.

The media reports and the inquiry findings state 1,216 homicides leading to a conviction were committed by patients or people with mental health illness over the period from 2001-2010 in the UK.

The report found that:

  • homicides per year by patients or people with mental health illness have fallen from 163 in 2004 to 86 in 2010.
  • suicide by mental health patients has risen – although this could be partly due to a change in the way causes of death are recorded. The researchers think that the figures represent a true rise in patient suicide, reflecting the rise in suicide in the general population


How accurate is The Sun’s coverage?

The Sun reports that: “A Sun investigation today reveals disturbing failings in Britain’s mental health system that have allowed high-risk patients to kill 1,200 people in a decade.”

Despite this not being The Sun’s own investigation, the numbers are approximately right. However, the interpretation is misleading.

The Sun attributes these homicides to mental health patients, but it should be noted that these 1,216 homicides were perpetrated either by:

  • any person who had come in contact with mental health services in the prior 12 months – patient homicide (738 homicides)
  • people with symptoms of mental health illness, defined as people who experience symptoms of hypomania, depression, delusions, hallucinations or other psychotic symptoms of any severity at the time of the offense (666 homicides)

There is some overlap between the groups and therefore the total comes to more than 1,216.

As the report states: “Not all perpetrators who had symptoms of mental illness at the time of the offence were patients and not all patients had symptoms of mental illness at the time of the offence.” Yet, the Sun’s coverage goes on to describe cases of homicide committed by people with mental health issues.


What did the report conclude?

The report found that over 10 years there were 738 patient homicides by people who had been in contact with mental health services within the past 12 months. To put these numbers in context, over the same period there were 6,605 homicide convictions just in England (so around 10% were committed by “mental patients”).

The inquiry also found that the average number of patients committing homicide per year in the UK (2001-2010) was 74 per year – a more meaningful headline figure. Because there are sometimes multiple victims, the corresponding figure for victims, taking account of multiple homicides, is 122 per year. Both these figures appear to be falling each year.

While the Sun focussed on several cases of people with schizophrenia, the inquiry actually found that many patient homicides were committed by people who, it says, did not have "severe" mental illness and instead had a primary diagnosis of personality disorder or drug and alcohol misuse. The number of patient homicides varied widely by diagnosis. The five main mental illnesses diagnosed within 12 months were:

  • schizophrenia
  • affective disorder
  • personality disorder
  • alcohol dependence or misuse
  • drug dependence or misuse

The perpetrators who had symptoms of mental illness (hypomania, depression, delusions, hallucinations, or other psychotic symptoms such as passivity) at the time of the homicide were defined as mentally ill at the time of the offence, however severe these symptoms were. For these people:

  • while symptoms of mental illness were present, we do not know if these symptoms caused them to commit the homicide
  • on average, 67 people per year committed homicide whilst experiencing an abnormal mental state
  • most of these people were not under mental health care and therefore most were not preventable by mental health services
  • these cases provide an indication of the total “contribution” to homicide from mental illness

The overlap between these two groups was limited. For example 35% of “patients” were mentally ill at the time of offence and 38% of those who were mentally ill at the time of offence were “patients”. The results also show that victims of patient homicide are more likely to be spouses or family members than strangers (for all four countries in the UK).


What else do we know about mental health and crime?

People with mental health illness are more likely to be the victims rather than the perpetrators of crime. In fact, new research has found that people with mental illness are three times more likely to be victims of crime than the general population.

It is important to understand what has contributed to people’s deaths, especially where there have been failings in the system of care. It is unclear from the inquiry’s report exactly how many homicides were preventable, but the Sun’s coverage gives an unrepresentative and unnecessarily stigmatising view of the facts.


Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.

Analysis by Bazian

Edited by NHS Choices


How helpful is this page?

Average rating

Based on 5 ratings

All ratings

3  ratings
1  ratings
0  ratings
1  ratings
0  ratings

Add your rating

Useful links

NHS Choices

News analysis: DSM-5 mental health guide controversy

A new version of a major guide to mental health was published in May 2013 amid a storm of controversy and bitter criticism

Why am I so angry?

Why we get angry, plus how learning how to deal with anger can reduce health risks and improve relationships

One in four affected

One in four of us will have mental health problems at some time in our lives. Find out how to get help

Time to change people's minds

Psychiatric nurse Lol Butterfield used his experience of depression to advise a character in the ITV soap Emmerdale

Coping with bereavement

A bereavement counsellor explains what bereavement is, how to cope and where to go for help and support

Free audio guides to boost your mood

Eight Moodzone mental wellbeing audio guides designed to help you better understand the problems you may be facing in your life