Gangs Matrix

The Gangs Matrix is a police database consisting of the names the Metropolitan Police perceive to be in a gang and likely to commit violence. The Gangs Matrix was created as a response to the 2011 riots which started in Tottenham and spread across the UK. At StopWatch we are actively trying to encourage people to check if their name is on the Matrix and support those who wish to get their names removed.

The Gangs Matrix is the cause of much controversy as it is disproportionately made up of young black males. StopWatch recently published a report called The Colour of Injustice: ‘Race’, drug and law enforcement in England and Wales which highlighted the disproportional use of stop and search, and the over-policing of black communities. 

In addition to StopWatch’s work, Amnesty International have also been campaigning against the use of the Matrix and last year published a report called Trapped In The Matrix: Secrecy, stigma, and bias in the Met’s Gangs Database. The Amnesty report found numerous human rights and data protection issues with the Gangs Matrix. The composition of the database was particularly striking with:

  • 80% are aged between 16–24 years old
  • 64% of those on the matrix are ranked as green or low risk
  • 78% are black males
  • 75% have been victims of violence
  • 35% have never been convicted of a serious offence 
  • 15% are minors

How does it work?

Individuals can put on the matrix for a variety of reasons ranging from social media activity, known criminal activity and can be referred by third party institutions such as housing associations, Pupil Referral Units (PRUs) and other children and community services. You may not have been involved in any criminal activities to be listed on the Gangs Matrix. A third of individuals on the matrix have never committed a crime.


The Gangs Matrix uses an algorithm to determine a score which is then colour coded. Each nominal on the database is categorised as either Green Yellow or Red. The colour is intended to reflect the extent to which that individual poses a risk to others. An individual’s colour score determines the extent to which the police and partner agencies interact with the suspected “gang member”.

Each borough creates their own localised Matrix and is in charge of adding and removing names. The data is stored and relayed back to a centralised database. The personal data of individuals recorded on the Matrix will include some or all the fields of the following information:

  • Full name
  • Nickname
  • Date of birth
  • Home address
  • Ethnicity code
  • Information on whether the individual is a prolific firearms offender or knife carrier
  • Rank and score per Matrix criteria
  • Police intelligence information
  • Partner intelligence information

What happens if I'm on the Matrix?

The repercussions of being on the database can vary. The Information Commissioner’s Office (ICO) enforcement notice states that the Metropolitan Police Service (MPS) will seek to take enforcement action against identified gang nominals across a range of civil and criminal areas. This means that where prosecution for specific gang-related offences is not possible, “gang members” are targeted more generally. This can include disruption of:

  • Prison license conditions
  • Benefits
  • Housing (including eviction)
  • TV licensing

And / or enforcement of:

  • Increased stop and search
  • Immigration action
  • Parking enforcement / license conditions
  • Exclusions

Stop-Watch, Amnesty International and the ICO have all released reports questioning the legitimacy of the Gangs Matrix. These reports highlight the disproportionality of black young males currently stored on the system and the illegality of sharing data with third party institutions. The Mayor’s Office for Policing and Crime (MOPAC) have also released its review of the Gangs Matrix providing an overlook of the Gangs Matrix’s use, composition and practicalities.

How do I know if I'm on the Matrix?

To find out if you are on the Matrix you must make a Subject Access Request (SAR) to your local police station (click on the image for a copy). Templates and information on what you will need to take with you can be found below. If you would like some assistance, or have any questions regarding making a Subject Access Request, feel free to contact us: info@stop-watch.org

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