Violence involving prisoners


Last updated 14 May 2019 - see all updates

1. Main facts and figures

  • overall, there were 18,405 recorded assaults in public prisons in England and Wales in 2017, compared with 16,782 in 2016 – an increase of 10%
  • between 2012 and 2017, there was an increase in the rate of assaults per 1,000 prisoners in all ethnic groups, with the overall rate more than doubling for assailants in this period
  • prisoners with Mixed ethnicity were more likely than any other ethnic group to be involved in assaults in 2017, either as the assailant, the victim, or in an incident where the victim or assailant wasn’t clear (labelled as ‘fighter’ in the charts and tables)
Things you need to know

Previous edition of this page should not be used as there was a mistake in the labelling of the ethnicity classification. This has been corrected in this version.

This data records the number of violent incidents, not the number of individuals involved in violent incidents, nor how often each prisoner was involved. Individuals may therefore be included in the data more than once. This means that the rate of violent incidents per 1,000 prisoners should be considered with some caution.

The data is based on all assault incidents, but does not include information about staff or visitors who may have been victims or otherwise involved.

What the data measures

This data measures the number and rate of violent incidents per 1,000 prisoners in England and Wales in each calendar year from 2012 to 2017. The data is broken down by ethnicity.

There are separate breakdowns for the different roles prisoners played in each incident:

  • assailants are defined as prisoners who assault another prisoner
  • victims are prisoners assaulted by another prisoner
  • fighters are prisoners involved in a violent incident where they and one or more prisoners use violence and there is no clear assailant or victim

The data comes from the incident reporting system of Her Majesty’s Prison and Probation Service (HMPPS), formerly the National Offender Management Service (NOMS).

The ethnic categories used in this data

Prisoners reported their own ethnicity according to the following broad categories from the 2011 Census:

  • Asian/Asian British
  • Black/African/Caribbean/Black British
  • Mixed/Multiple ethnic groups
  • White
  • Other

2. By ethnicity (all violent incidents)

Violent incidents per 1,000 prisoners, and total number of incidents, by ethnicity and role in the incident (assailant, victim or fighter)
Assailant Fighter Victim
Ethnicity Assailant Incidents per 1,000 prisoners Assailant Number of incidents Fighter Incidents per 1,000 prisoners Fighter Number of incidents Victim Incidents per 1,000 prisoners Victim Number of incidents
Asian 167 1,158 141 977 153 1,060
Black 379 4,050 299 3,197 165 1,758
Mixed 432 1,622 300 1,126 188 707
White 180 11,207 124 7,769 148 9,231
Other 269 293 239 260 169 184
Unknown N/A* 75 N/A* 58 N/A* 75

Download table data for ‘By ethnicity (all violent incidents)’ (CSV) Source data for ‘By ethnicity (all violent incidents)’ (CSV)

Summary of Violence involving prisoners By ethnicity (all violent incidents) Summary

This data shows that:

  • in 2017, prisoners from the Mixed ethnic group were more likely than any other group to be assailants, victims or fighters – for every 1,000 prisoners of Mixed ethnicity, there were 432 incidents where they assaulted another prisoner, 188 incidents where they were victims of assault, and 300 incidents with no clear victim or assailant (labelled as 'fighter' in the chart and table)
  • Black prisoners were the second most likely ethnic group to be assailants (at 379 incidents per 1,000 prisoners) or fighters (at 299 incidents per 1,000 prisoners)
  • Asian prisoners were least likely out of all ethnic groups to be assailants (at 167 incidents per 1,000 prisoners)
  • White prisoners were the least likely out of all ethnic groups to be fighters (at 124 incidents per 1,000 prisoners) and victims (at 148 incidents per 1,000 prisoners)

3. By ethnicity over time (assaults only)

Assaults per 1,000 prisoners, and number of assaults, by ethnicity over time
Asian Black Mixed White Other Unknown
Time Asian Assaults per 1,000 prisoners Asian Number Black Assaults per 1,000 prisoners Black Number Mixed Assaults per 1,000 prisoners Mixed Number White Assaults per 1,000 prisoners White Number Other Assaults per 1,000 prisoners Other Number Unknown Assaults per 1,000 prisoners Unknown Number
2012 71 454 180 2,009 182 579 72 4,458 95 94 N/A* 211
2013 96 619 188 2,031 217 703 78 4,787 111 111 N/A* 145
2014 89 592 217 2,325 262 905 95 5,914 120 123 N/A* 80
2015 118 810 285 3,017 336 1,177 127 8,026 163 160 N/A* 60
2016 150 1,032 339 3,549 405 1,465 167 10,442 221 225 N/A* 69
2017 167 1,158 379 4,050 432 1,622 180 11,207 269 293 N/A* 75

Download table data for ‘By ethnicity over time (assaults only)’ (CSV) Source data for ‘By ethnicity over time (assaults only)’ (CSV)

Summary of Violence involving prisoners By ethnicity over time (assaults only) Summary

This data shows that:

  • between 2012 and 2017, the rate of assaults per 1,000 prisoners more than doubled for assailants in every ethnic group
  • in every year between 2012 and 2017, the Mixed ethnic group had the highest rate of incidents per 1,000 prisoners where they were the assailant – the rate increased from 182 to 432 incidents per 1,000 prisoners during that period, almost 2.5 times as many
  • Black prisoners accounted for the second highest rate of incidents per 1,000 prisoners where they were the assailant – but they also had the smallest percentage increase in the rate per 1,000 prisoners between 2012 and 2017 (from 180 to 379 incidents per 1,000 prisoners, just over twice as many)

4. Methodology

Rates by ethnicity have been taken from the HMPPS Offender Equalities Statistics bulletin. Numbers of incidents have been taken from the Ministry of Justice’s Safety in Custody statistics bulletin.

To calculate the prisoner population, a 12-month average (based on prisoner counts done at the start of every month) was used where this data was available. This data was not available for the prisoner population by age or by ethnicity, so quarterly data was used to calculate the prisoner population.

Ethnicity is based on self-reporting by prisoners and has not been independently validated. About 95% of prisoners reported their ethnicity for each year of the period studied.

Information is provided by prisons and published by the Ministry of Justice after data checks are completed.


Rates per 1,000 prisoners are rounded to the nearest whole number. You can see rates rounded to 1 decimal place if you download the data.

Related publications

GOV.UK Safety in custody statistics

Quality and methodology information

5. Data sources


Type of data

Administrative data

Type of statistic

Official statistics


Ministry of Justice

Publication frequency


Purpose of data source

This data is used by government to:

  • inform policy development
  • monitor the impact of changes over time
  • model future changes and their impact on the prison system

6. Download the data

Violence involving prisoners - Spreadsheet (csv) 27 KB

This file contains the following: ethnicity, year, value and numerator