Rival gangs use the songs to goad each other - and this often escalates into real-world violence. As a result, the music has offered prosecutors the chance to link murderous thugs to their crimes.
BBC News
By Steve Swann
image captionDrill rap videos are increasingly being used as evidence in trials
Drill music has captured headlines since it started to emerge in the UK in 2012. With its often provocative lyrics, it s been blamed by police for fuelling violence.
It is also increasingly being used as evidence in trials with courts hearing allegations it incites gang rivalries. But some defence lawyers and academics say it stops defendants - often young black men - getting a fair trial. The BBC has looked into the detail of dozens of prosecutions across the UK.
Wood Green on 2 February 2019 was more reminiscent of a Hollywood film than a winter s night in north London , the Old Bailey was told.