Mayor publishes Gangs Matrix review

21 December 2018

Gangs Matrix – Mayor publishes review recommending comprehensive overhaul

  • Review makes nine recommendations, including investigation into whether a disproportionate number of young black men on the Matrix is legitimate
  • Recognises the Gangs Matrix has a positive impact on reducing offending or being a victim of violence
  • Sadiq says Matrix overhaul should be completed by December 2019


The Mayor of London, Sadiq Khan, has today published a wide-ranging review of the Metropolitan Police’s Gangs Matrix, which recommends a comprehensive overhaul of the database to restore trust in its use and ensure it is used both lawfully and proportionately.


The Gangs Matrix was set up in the aftermath of the 2011 riots by the Met to identify those at risk of committing, or being a victim of, gang-related violence in London. The Matrix has proved controversial due to issues in the way individuals are added and, when they are removed, the way data is stored securely and applied consistently. Concerns have also been raised that it leads to discrimination against certain communities, resulting in mistrust of the police and rising tensions.


The review, which fulfils a commitment in the Mayor’s Manifesto and his Police and Crime Plan, includes detailed analysis of more than 7,000 people who have been on the Gangs Matrix, together with surveys of frontline local authority staff and those in communities directly affected by violence. It makes nine recommendations, that when implemented, will help make the Matrix more transparent and bring it into line with data protection legislation. The report calls for this comprehensive overhaul to be completed by the end of 2019 and for the Matrix to be subject to annual reviews to ensure it is operating effectively.


The review found: 


  • That while the Gangs Matrix is a useful law enforcement tool for reducing violent crime in London, it requires a comprehensive overhaul
  • The Matrix has a positive impact on reducing levels both of offending and being a victim
  • That reductions in offending are sustained even after an individual is removed from the Matrix
  • A person’s involvement with the police does drop after being removed from the Matrix
  • Significant issues around public understanding of the Gangs Matrix and a lack of transparency by the Met in communicating its aims and the purpose of the Matrix – not only to the public but also to local authorities.
  • Inconsistencies and gaps in the management, processes and oversight of the Gangs Matrix across London.
  • That the representation of young black men on the Matrix is disproportionate to their likelihood of either causing or being a victim of gang violence and communities have deep reservations about how it operates. Further investigation is to be carried out to understand if this disproportionality is legitimate and to be transparent about this process.
  • That three quarters of those on the Matrix were under the age of 25, and that 80 per cent were black.


The review also highlighted that on average a person spends more than two years on the Matrix and at any time 38 per cent have a zero-harm score – reflecting the lowest risk of committing violence. The Met is recommended to carry out a full review of those with a zero-harm score against stringent criteria and if they do not meet those standards, they should be immediately removed.


It also recommends that the Mayor’s Office for Policing and Crime (MOPAC) and the Met should engage with the Equality and Human Rights Commission as they deliver the recommendations in producing an Equalities Impact Assessment.


In compiling the review, MOPAC also worked closely with the Information Commissioner’s Office, which published an investigation into the Matrix last month which found it led to multiple and serious breaches of data protection laws.


The Mayor of London, Sadiq Khan, said: “I made a firm commitment to Londoners to carry out a full review of the Met’s Gangs Matrix with the aim of restoring trust and confidence in the way it is used by the police.


“The review has shown that the Gangs Matrix can be an effective enforcement tool and is helping to tackle violence on our streets. But to many Londoners, the way it is applied and enforced is a cause for concern and it needs to be comprehensively overhauled to ensure it is used lawfully and proportionately.  


“By implementing the review’s nine recommendations, the Matrix can address the serious breaches of data protection laws and ensure only those at genuine risk of causing or being a victim of violence are included. It’s important these recommendations are carried out quickly and transparently to ensure Londoners have confidence in how it is used by the Met.”        


- Ends –


Notes to editors

  • A review of the Metropolitan Police Service Gangs Matrix can be found here:
  • A reference group of experts, and people working with gangs and in communities, was convened to advise on the review. The review also had independent legal advice.
  • While gang-flagged violence accounts for a relatively small proportion of overall levels of violent crime in London, it represents a significant percentage of the most serious and harmful offending and victimisation. 57 per cent of gang-related stabbings featured a serious or fatal injury, compared to 34 per cent of non-gang-flagged stabbings.
  • Those on the database are split into three harm bandings with red consisting of those deemed being the highest risk of offending and green the lowest.


The nine recommendations are:


- The Gangs Matrix should be comprehensively overhauled and reviewed annually to ensure the right people are on it 

- A thorough reappraisal of the Green category, with a focus on those with a zero-harm score. If an individual does not meet strict criteria they should be removed. 

- Both MOPAC and the Met engage with the Equality and Human Rights Commission as they deliver the recommendations in this Review and work to produce an Equalities Impact Assessment- The Met should strengthen its governance of the Matrix creating single points of responsibility to ensure no discriminatory practice and data breaches are properly assessed and mitigated.

- The Met improves data capture across all aspects of the Matrix process.

- The Met urgently improves its current Matrix processes to ensure that personal data and information are stored, managed, shared, protected and transmitted safely and appropriately.

- The Met improves transparency by producing, by the end of February 2019, publicly available information about how the Matrix works, how information is shared and the benefits of an individual being on the database.

- MOPAC will oversee implementation of the recommendations by requiring the Met to report annually on progress against recommendations to the Ethics and Audit panels and publishing those reports.

- The Met should consider whether the lessons learned from this review are applicable to its other operational tools.

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