Met Police Gangs Violence Matrix

February 2022

According to the Independent, London's Metropolitan Police faces legal action over Gangs Violence Matrix (GVM), a controversial database of alleged street gang members.

The GVM (also known as Gangs Matrix) has been subject to investigations and studies by Amnesty, Liberty, StopWatch and other human rights organisations and academics.

'Racially discriminatory' and 'unfit for purpose'

It has also been the subject of a high-profile review (pdf) ordered by London mayor Sadiq Khan and an independent review commissioned by then UK Prime minister David Cameron of England and Wales' criminal justice system by David Lammy MP.

These studies variously conclude that the GVM discriminates against racial and ethnic minorities and, according (pdf) to Amnesty, is 'unfit for purpose'. Both are charges also regularly levelled at the Met Police force.

In 2018, the Met Police's use of Gangs Matrix was served (pdf) with an enforcement notice by the UK privacy commissioner for 'potentially' breaking data protection laws, and for its failure to distinguish victims of crime and offenders.

Strategic and operational opacity

Secretly established in 2011, the GVM uses one or more algorithms to rank and categorise people included on the database, based on the risk each 'gang member' poses to others, and the extent to which the police and partner agencies interact with that person.

The Met does not inform people included on the database. Nor is there is any mechanism by which those included can discover what information is help about them, ask for their data to be reviewed or removed, or appeal against their inclusion.

It is understood the database is shared with other UK authorities such as immigration enforcement.

Operator: Metropolitan Police Service (MPS)
Metropolitan Police Service (MPS)
Govt - police
Predict gang violence risk
Technology: Ranking algorithm
Bias/discrimination - race, ethnicity, income, geography; Accuracy/reliability; Privacy
Governance; Complaints/appeals; Black box


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