Suicide in prison: a new study on risk factors in the prison environment

In many countries, rates of suicide in prison are high, and it is recognised that prisons can exacerbate mental ill health, heighten vulnerability and increase the risk of self-harm and suicide. Taanvi Ramesh, an Assistant Psychologist in the Mental Health Team at HMP Bedford, discusses the recent international study that she and others conducted on suicide rates in 24 high-income countries in Europe, Australasia, and North America, which compared general and prison population suicide rates and explored the links between suicide and incarceration rates and prison-related factors.

People in prison have long been recognised as a vulnerable population at risk of suicide, and there has been significant research to identify associated risk factors. However, rates of prisoner suicides remain elevated in many high-income countries, indicating that the current approach is not effective in preventing these deaths. While research into the individual-level characteristics associated with prisoner suicide has been beneficial to a degree, a multilevel approach incorporating risk factors related to the prison environment alongside individual-level risk factors may be necessary to reduce these preventable deaths in custody.

An international study,¹ which I conducted with Professors Seena Fazel and Keith Hawton at the University of Oxford, shows the increased risk of suicide for men and women in prison, compared to the general population, in 24 high-income countries between 2011–2014. Our study found that the risk of suicide increased at least three-fold for male prisoners compared to the general male population. For females, this risk was amplified, with female prisoners being at least nine times more likely to die from suicide compared to the general female population.

Female prisoners [are] at least nine times more likely to die from suicide compared to the general female population.

Our findings showed that the countries with the lowest rates of prisoner suicide were the USA, Poland and Canada, and the countries with the highest rates of prisoner suicides were Norway and France. Norwegian prisons had an annual average of 180 prisoner suicides per 100,000 members of the prisoner population, while the USA had an annual average of just 23 prisoner suicides per 100,000 members of the prison population. In addition, the country with a substantially increased risk of suicide amongst prisoners compared to the general population was Norway: Norwegian prisoners were 14 times more likely than their general population counterparts to die of suicide. Other countries with high levels of increased risk were Italy and Portugal.

For the 24 countries, we collected data on rates of incarceration indicating the annual numbers of individuals imprisoned per 100,000 members of the general population. An earlier study in 2011, conducted by Professor Fazel and colleagues, found no association between rates of incarceration and rates of prisoner suicides across 12 high-income countries. However, our 2017 study of 24 countries found that there was an association between rates of incarceration and rates of prisoner suicide: rates of prisoner suicide were higher in countries where fewer individuals were imprisoned per 100,000 members of the general population, and vice versa.

Our proposed explanation for this link relates to the characteristics of offenders who are imprisoned in countries with low incarceration rates. If a country is imprisoning fewer offenders per 100,000 members of the general population, this is likely to indicate that only offenders that have committed more serious or violent offences are imprisoned, while those charged with minor or non-violent offences are given community sentences. As such, in countries with low incarceration rates, the prisoner population will include a large proportion of people who have committed more serious or violent offences and, most likely, a large proportion of people suffering from mental illness. Having committed a serious or violent offence has been found to be associated with an increased risk of suicide and, similarly, evidence of mental illness has also been found to be linked to increased suicide risk. As such, lower incarceration rates may mean that the prison population is riskier and more vulnerable, thereby resulting in higher rates of prisoner suicide.

Lower incarceration rates may mean that the prison population is riskier and more vulnerable, thereby resulting in higher rates of prisoner suicide.

Individual-level risk factors linked to prisoner suicide were identified by a 2016 study, which found that factors linked with a higher risk of prisoner suicide included a history of self-harm or suicide attempts, prior psychiatric treatment, adverse life events, a family history of suicide, a prior prison stay, a short stay (fewer than 30 days) in prison for the current prison stay, and current mental health problems, primarily major depressive symptoms, anxiety disorders and psychosis.

Although this provides a useful insight into individual-level risk factors, less is known about how the prison environment may play a role in the increase of suicide risk. Therefore, we decided to also investigate a number of factors related to the prison environment. These included the ratio of prison staff to prisoners, prisoner population turnover, and average cost per prisoner per day, amongst others; none of the nine investigated prison characteristics were found to be associated with rates of prisoner suicide.

A frequently discussed aspect of the prison environment is the increased levels of overcrowding of prisons in recent years. Globally, the prison population continues to rise year on year and, along with continual governmental constraints on funding, prison environments have undergone changes to accommodate offenders in custody. For example, some prisons have converted single cells to shared cells in order to house greater numbers of offenders. The Institute for Criminal Policy Research reported that in 2017, 119 out of 205 countries reported prisoner populations exceeding their official prison capacity.

Prisoner suicide is unlikely to have singular associations with environmental factors, such as overcrowding, as suicide involves a more complex combination of risk factors.

This raises the question of whether the increased rate of overcrowding in prisons might be associated with rates of prisoner suicide. A 2006 study of prisoners in England and Wales found that prisons with higher rates of overcrowding also had higher rates of prisoner suicide. However, our study of 24 countries found there to be no association between rates of overcrowding and rates of prisoner suicide. A possible explanation for this may be that having a cellmate is a protective factor against suicide, perhaps due to social interaction or, if a suicide attempt occurs, having someone there who can alert staff and/or intervene quickly.

Another likely explanation for this finding – and for the finding that there are no links with other factors related to the prison environment – is that prisoner suicide is unlikely to have singular associations with environmental factors, such as overcrowding, as suicide involves a more complex combination of risk factors. Prison overcrowding may be a contributory factor, but our study shows that changes to overcrowding in prisons alone is unlikely to reduce rates of prisoner suicide. Similarly, although the ratio of prisoners to prison staff may not be linked to rates of suicide, it is likely that the quality of the interactions with prison staff will have an impact. However, this factor has not been well researched, nor can it be easily investigated on a large scale. Further work is required to assess these more sensitive markers of prisoner life and their impact on prisoner suicide.

National strategies that aim to prevent suicide in prisons need to be implemented effectively, informed by the evidence.

Our recommendation therefore for future research is to advise a multilevel approach to identify interactions of individual-level risk factors together with factors related to the prison environment that may lead to increased risk of prisoner suicide. For our study, data was unavailable for a number of prison-level factors that may have been more closely related to prisoner suicide rates; for example, rates of prisoners engaging in mental health treatments, assault rates within prisons, amount of meaningful activity offered to prisoners, as well as access to methods of suicide, such as ligature points (i.e. access to bars from which to attempt hanging).

Of course, research into risk factors alone will not be enough to reduce the rate of prisoner suicides. National strategies that aim to prevent suicide in prisons need to be implemented effectively, informed by the evidence. These strategies need to draw on all areas of the criminal justice system to incorporate targeted interventions for both individual-level and prison-level characteristics associated with increased risk. The National Institute for Health and Care Excellence (NICE) in England and Wales is currently drafting guidance for the prevention of suicides in custodial settings; these guidelines will be informed by research in the field and are aimed at informing the national prison and health services of the best practice for preventing these deaths.

Internationally, prisoner suicide remains a challenge. However, with constrained funding, staff shortages and limited research, current policy has not been able to effectively target and prevent these deaths. With prisoners globally at least three times more likely than their general population counterparts to die by suicide, suicide risk in prison needs to become much more of a government priority in all countries, before more vulnerable individuals take their own lives.

¹The paper is titled ‘Suicide in prisons: an international study of prevalence and contributory factors’. It is open access and available at: http://www.thelancet.com/journals/lanpsy/article/PIIS2215-0366(17)30430-3/supplemental

More information

PRI recently published Mental health in prison: A short guide for prison staff, which seeks to help prison staff understand and respond appropriately to the mental health needs of adult prisoners. It focuses on how prison staff can promote and protect mental health and well-being and enable those with existing conditions to function better in the prison environment. Guidance is based on a human rights-based and holistic approach, as required by the UN Standard Minimum Rules for the Treatment of Prisoners (the Nelson Mandela Rules).