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Impact case study

Preventing the Risk of Suicide and Self-harm Behaviour in Prison Populations

Unit(s) of assessment: Psychology, Psychiatry and Neuroscience

Research theme: Health and Wellbeing

School: School of Social Sciences


Prison suicide rates in England and Wales are eight times that of the general population; with self-harm rates at a record high. NTU research led to changes in policy and practice, at a national and regional level, regarding assessment and prevention of suicide and self-harm, contributing to demonstrable reductions in suicide and self-harm within UK justice services. Specifically, this research has underpinned:

  • A new HMPPS-approved diagnostic tool to improve safety in over 100 prisons
  • National guidance issued to thousands of prison and probation staff
  • Innovative assessment and interventions minimising suicide and self-harm risk.
  • Recommendations in two NICE guidance documents.

Research background

In the UK, people in contact with the criminal justice system (CJS) are high risk populations for suicide and self-harm behaviour. At a time of unprecedented levels of suicide and self-harm in prisons and after release, there is regulatory body, expert and government agreement that prisons must take action to address critical failures and protect the lives of people in prison and the wider CJS. The Ministry of Justice Safety in Custody statistics for England and Wales (March 2020) reported 76 suicides in prison over a 12-month period, a rate of 90 per 100,000 against a suicide rate of 11 per 100,000 in the general population as reported by the Office for National Statistics in 2020. Furthermore, self-harm in prison was reported at a record high (64,552, up 11% from previous year).

Although the risks and management of harmful behaviours have been widely researched, literature around self-harm and violent behaviour has remained largely separate, both in community and in prison contexts. NTU research into organisational and theoretical models of self-harm and suicide, and its relationship to violence, has led the way in demonstrating how research methodologies may improve risk management and prevention in UK justice services. This research covers two areas:

Dual Harm: identifying characteristics for dual violence and self-harm behaviour in prison (2014-2018)

NTU researchers conducted the first study on ‘dual harm’ behaviour (exhibiting both violence and self-harm) in UK prisons and to evaluate their wider prison behaviour and offending characteristics. This study was the first to identify the institutional behaviour profile of complex, high-risk dual harm prisoners in a range of prison environments. Official data on in-prison incidents, demographics and offending information were analysed for 326 prisoners in two prisons in England. Key findings from this research demonstrated that up to 42% of offenders who assault others will also engage in self harm. The profile for dual harm prisoners notably differed from other groups, with far greater proportions of damage to property and fire-setting. A recent study (2017-8) on self-harm by dual harm prisoners demonstrated their increased risk of self-harm and excessive contribution to the overall incident burden on prisons. The research also demonstrated that restrictive regimes (including segregation) increased the likelihood of more lethal methods of self-harm. These findings led to changes in management guidance for prisons including a wider use of joint risk assessment and single case management suggested for prisoners with a dual-harm profile.

Suicide Prevention: examining pre-custody and custody assessment, intervention and evaluation (2010-2018)

Research studies (2013-14) confirmed the utility of psychological theories in predicting self-harm and suicide in prisons and demonstrated that changes to organisational factors, senior management support for cultural change, and cross-professional collaborative working can significantly reduce suicide in a prison. In 2015, Associate Professor Slade co-authored a study which examined the prevalence of suicide ideation amongst people arrested and taken into police custody, and then referred to a mental health service operating in the police stations. This service was funded by Guy’s and St Thomas’ Charity. This pre-custody research identified the prevalence of suicide risk within Police Custody and concluded the current systems of assessment and prioritisation fell short in their response to suicide risk within pre-custody (police/court) stages leading to acute severe mental illness and suicidality in prison.

Following this study, NTU co-led a study with South London and Maudsley NHS Foundation Trust, funded by NHS England, which evaluated pathways through the criminal justice system for prisoners under the care of prison mental health services. This study, funded by NHS England, aimed to examine the pre-custody pathway for people with serious mental health disorders in prison. This study concluded that greater consistency in access to pre-prison health services in the criminal justice system is needed, especially for those with pre-existing vulnerabilities.

In 2018, Associate Professor Slade completed a systematic review in collaboration with the Samaritans, funded by the Ministry of Justice, which examined the differential effects of exposure to suicidal behaviour on prisoners. This review demonstrated that the negative effects of exposure are strongest in those with greatest proximity to the death and evidenced the most effective avenues of communication, emotional expression and peer support, directly informing the content and delivery format for a novel postvention intervention in prisons.


NTU research has directly informed successful risk assessment and prevention policy and protocols, including the first UK-wide HMPPS Safety Diagnostic Tool. NTU research has also changed NICE guidance and led to a novel suicide postvention service in prisons. These policies and tools are now standard practice in over 100 prisons and across all probation services in England and have improved safety and wellbeing for tens of thousands of people in prison or in contact with probation services. Regionally, testimonials demonstrate that NTU research has underpinned changes in the day-to-day practices of hundreds of staff within UK prison and probation services and police forces. NTU research has informed the development of effective practices which have demonstrably reduced suicide and self-harm rates amongst those in the criminal justice system in the UK.

Informing national assessment and intervention

Slade’s work has been incorporated into the new screening assessment undertaken by Police Officers after police interviews to identify individuals at risk of suicide. An evaluation (August 2019) led to a revised assessment strategy which was rolled out across Nottinghamshire Police at the end of 2019; with an adapted version implemented by the National Probation Service for all Approved Premises residents (750-1200 per month) in Summer 2020. Detective Inspector Dowson with Nottinghamshire Police recognised that the “novel assessment devised by Dr Slade was a huge step forward to ensure we offer comprehensive cover in our attempts to identify and reduce the likelihood that individuals in police custody will attempt or die by suicide. Following Dr Slade’s research, almost 1 in 3 of attendees now receive the additional support, referral or guidance they need…in 2019/2020, there was a reduction from 5 to 0 apparent suicide after contact with Police”.

Slade’s systematic review on the impact of exposure to suicidal behaviour, directly informed the requirements for a new intervention in prisons after a suicide by Samaritans, an internationally recognised authority on suicide prevention. The MoJ/HMPPS committed to improving access to support for people in prisons following self-inflicted deaths, through the provision of this service across England, in The Cross-Government Suicide Prevention Workplan, which commits every area of Government to taking action on suicide. The intervention was initially piloted in 15 prisons in England in 2019. Slade’s research confirmed the effectiveness of the intervention with the evaluation report stating “Taken together, the above findings provide evidence of feasibility and effectiveness of some key elements of Postvention Support…. it did, on balance of probabilities, have a positive effect on emotional coping and current suicidality".

Informing recommendations in NICE guidance

Slade’s publication is one of two peer-reviewed qualitative studies on preventing suicide in community and custodial settings to be cited by the National Institute for Health and Excellence (NICE) supporting the specific recommendation that each prison should set up a multi-agency partnership for suicide prevention in residential custodial and detention settings, including clear leadership. Two of Slade’s publications are cited in the NICE Guideline ‘Mental health of adults in contact with the criminal justice system’, providing evidence of significant limitations within current practice and underpinning the need for the changes to NICE guidance.

Informing national risk assessment procedures for HM Prison Service and National Probation Service

NTU research directly informed changes to the revised HMPPS-wide Safety Diagnostic Tool (SDT), which formed a core element of the HM Prison and Probation Service’s National Safety Strategy as outlined by the Prisons Minister to the Justice Committee in June 2019. This tool was revised, directly based on Slade’s research to identify prisoners with a history of dual harm; with practice gance provided in the national Dual Harm Safety Briefing. There are 45,000 registered users for the SDT, with over 200 staff, across over 100 public and private prisons accessing data daily, to inform risk assessment and strategic management for violence and selfharm. Slade’s research underpinned specific guidance in the MoJ OASys Risk of Serious Harm guidance for harm to self and dual harm; the core guidance document for the risk assessment for over 250,000 people in prison or under probation supervision in England and Wales. These changes were based directly on Slade’s work on the patterns and management of dual harm behaviour. Further, Slade’s research provided the theoretical framework for the key policy document: ‘Understanding Risk Guidance’ a national HMPPS document in 2017 to support all prison staff in suicide risk decision making.

Informing prevention and practice development with HMP Nottingham and HMP Lowdham Grange

NTU research into organisational approaches to suicide prevention in prison underpinned a rapid risk review of eight self-inflicted deaths in HMP Nottingham. This review was used to inform HMP Nottingham’s Suicide Prevention policy and action plan. Recommendations from this review contributed to a demonstrable reduction in risk factors contributing to suicide in HMP Nottingham. As reported by the Deputy Governor of HMP Nottingham, the review, which ‘drew directly from [Slade’s] research’ was ‘extremely valuable and allowed swift action to be taken, with the recommendations from the report accepted and leading to changes to both policy and practice’. The review resulted in notable changes to the “process of delivering public protection notifications by probation and offender management staff (over 50 prisoners per month) and the development and implementation of a first-night interview by trained safer custody staff to every prisoner on entry […] (over 400 prisoners per month) [..]The Updated Review... identified that the [33%] reduction in deaths from 6 in 2017 to 4 in 2018 could be attributed to the reduction of specific areas of risk within our operational practice introduced as a direct result of the actions undertaken based upon the 2017 report [… ]. During 2019, there were no self-inflicted deaths in at HMP Nottingham”.

NTU research has also led to change at HMP Lowdham Grange, a SERCO-operated prison in the High Secure and Long Stay estate, with 920 male offenders. Based on NTU research, and following consultancy and an NTU training event, the prison developed a self-harm case formulation service and policy entitled ‘The psychological contributions to the Assessment, Care in Custody and Teamwork Process to aid the management of clients at risk to self’ which now provides theoretically informed assessments for those at risk of self-harm. The Head of Psychology reports “The service is…available to a significant… number of residents, with 34 clients in the last 6 months. I concur with the evaluation report ‘the utilisation of case formulations has a positive impact on the men in prison at risk of suicide and self-harm and is valuable to all of those involved’. This service has made a tangible difference to individuals at risk… we have seen a sustained reduction in suicide rates with no suicides recorded in 2019 or first half of 2020; along with a 23% reduction in self-harm between 2018 and 2019”.

Related staff


  • Slade, K. (2018) Dual harm: an exploration of the presence and characteristics for dual violence and self-harm behaviour in prison. Journal of Criminal Psychology, 8 (2), 97-111.
  • Slade, K., Forrester, A. and Baguley, T. (2020) Co-existing violence and self-harm: dual harm in an early-stage male prison population. Legal and Criminological Psychology, (2), 182-198.
  • Forrester, A., Samele, C., Slade, K., Craig, T. and Valmaggia, L. (2016) Suicide ideation amongst people referred for mental health assessment in police custody. Journal of Criminal Psychology, 6 (4), 146-156.
  • Slade, K., Samele, C., Valmaggia, L. and Forrester, A. (2016) Pathways through the criminal justice system for prisoners with acute and serious mental illness. Journal of Forensic and Legal Medicine, 44, 162-168.
  • Slade, K. and Forrester, A. (2015) Shifting the paradigm of prison suicide prevention through enhanced multi-agency integration and cultural change. Journal of Forensic Psychiatry and Psychology, 26(6):737-758.
  • Slade, K., Edelmann, R., Worrall, M. and Bray, D. (2014) Applying the Cry of Pain model as a predictor of deliberate self-harm in an early-stage adult male prison population, Legal and Criminological Psychology, 19 (1), pp. 131-146.
  • Slade, K., Scowcroft, L. and Dolan, B., 2019. The impact of exposure to suicidal behaviour in institutional settings, Nottingham: NTU. [external report for HMPPS]