The number of appeals against convictions involving music lyrics has more than tripled since drill music became popular in the UK in the past few years, according to research shared with the Guardian.

Lawyers, academics, artists and people convicted in criminal trials where rap and drill lyrics have been used as part of prosecution evidence are increasingly raising concerns that stereotyping is playing a part in these prosecutions.

They are part of a campaign called Art Not Evidence, which calls for restrictions on the use of creative and artistic expression as evidence in criminal trials. It asks that rap music in particular should not be used to unfairly implicate individuals in criminal charges and should only be used where directly linked to an alleged crime.

Campaigners want to see expert witnesses on this form of music in criminal prosecutions be independent, as opposed to police officers who are part of the prosecution case, along with procedural safeguards against stereotyping.

Dr Abenaa Owusu-Bempah, an associate professor of law at London School of Economics and a leading authority in this area, shared research data with the Guardian looking at cases involving rap and drill used as part of prosecution evidence between 2005 and 2025. Between 2005 and 2018, there were 20 cases, but between 2019 and the first part of 2025, there were 33 cases, more than a threefold increase in the yearly rate.

Owusu-Bempah said her data was “the tip of the iceberg” because many cases where rap and drill lyrics are used as part of a prosecution case in a criminal trial do not reach the court of appeal, even if there has been a miscarriage of justice.

Crimes where these lyrics and videos were used as part of the evidence include murder, attempted murder, conspiracy to cause grievous bodily harm and possession of a firearm. About half of the cases involve joint enterprise and many involve gang membership. Where ethnicity was specified in the data Owusu-Bempah gathered, the individuals were overwhelmingly black and male and in their teens or early 20s. While some of the appeals were allowed, many were dismissed.

At an event on Wednesday evening supported by Clifford Chance solicitors, speakers including Ademola Adedeji, one of the “Manchester 10”, whose conviction was quashed in January after police misidentified him in a drill video, called for changes in the law. He was imprisoned for 1,181 days. Adedeji told the Guardian that although he was overjoyed to have had his conviction overturned it was not possible to simply pick up on life where it left off when he was wrongfully convicted.

“I was just 17 when I was convicted,” said Adedeji. “I had a place at university to study law. If the jury hadn’t convicted me I would have finished my degree by now. Instead, I’m struggling to get back on track with going to university. These things are much harder after you’ve come out of prison.”

Ty’rone Haughton, a poet who also attended the event, said he believed that stereotyping played a key role in many of these prosecutions.

“We all use iambic pentameter, as Shakespeare did. I’m a poet and people feel less threatened by the word ‘poet’ than ‘rapper’, but all of my stuff is inspired by rap.

“If prosecutions are looking at the words of rap music, why aren’t they also looking at other genres of music too like rock and heavy metal? And what about the words politicians sometimes use? The lexicon has shifted but that doesn’t mean that rap is a form of criminal morse code. It is just people expressing themselves.”

Owusu-Bempah said: “In the majority of court of appeal cases I looked at, the appeals were against sentence with music treated as an aggravating factor. Drill started becoming really popular in 2018 and 2019 and that’s when we started seeing a big increase in cases. Drill music is not gang music.”

Crown Prosecution Service sources said that after a review of the issue, CPS will launch a consultation on future guidance relating to this issue in the coming weeks. The sources added that drill or rap music evidence is only used when it is important and relevant to a case.