The Metropolitan Police has defended the use of drill music lyrics as evidence in criminal cases following a campaign to change the law to restrict their use.

Drill rap videos and lyrics have been used as evidence in recent murder trials, and police have alleged that some of the music showed rappers boasting about real-life violent behaviour.

A report by the Centre on the Dynamics of Ethnicity said drill rap lyrics were used as evidence against 252 defendants between 2020 and 2023.

Campaign group Art Not Evidence, which includes lawyers and academics, is lobbying the government to change the law to create an assumption that “creative expression” is not admissible evidence.

Det Sgt Matt Corbin, who gives evidence in court as a police drill music expert, said it was “important” the force could use the material.

“There are people out there who unfortunately have committed horrendous and atrocious acts of violence,” he said. “We want to be able to use that material to secure convictions.”

Corbin said that if people chose to reveal true or criminal information within their music, then the police would use it as evidence.

Art Not Evidence said drill lyrics were being used in cases to show “gang aesthetics” which were “taken at face value and misinterpreted” by those with “a lack of knowledge of the culture of the genre”.

It said the use of lyrics to gain convictions for young black people contributed to existing racial disparities in the criminal justice system and created a “chilling effect” for freedom of expression.

Corbin said young people were driven to reveal true information in songs to gain status.

The officer acknowledged the debate around artistic expression, and said the force did not want to “demonise any particular genre of music”, adding that the lyrics must not be “overused” in court.

Valentina Locci, whose 15-year-old son Leonardo Reid was killed in Islington, north London, by gang members, said it was right that drill lyrics had been used to bring Leonardo’s killers to justice.

She said lyrics about someone’s death were “the most horrifying thing” for a member of a family to hear.

Locci said: “If it’s OK for you to write about a dead person then it should be OK for us to use them [the lyrics] in court to help bring justice.”

A spokesperson for Art Not Evidence said they welcomed the Met Police’s recognition that care and safeguards were needed when putting rap and drill music evidence before juries.

“The question is whether the safeguards currently in place are sufficient,” they said.

“Experience has shown that creative expression is still used in ways that invite prejudicial assumptions about criminality or gang membership, despite having limited or no relevance to the offence being tried.”

They called for “clear statutory safeguards” so that the music was only used when it was “genuinely relevant, reliable and not unduly prejudicial”.

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