The BAFTA-winning Kidulthood star, who investigates racism within the police force in a forthcoming BBC documentary, admits he was forced to come up with the unusual practise after frequent run-ins with the law.
He tells Britain's The Sun, ""You do come across officers who get angry when they discover you are not a criminal. They start pulling up the mats. It happens often enough to me that I keep a copy of one of my DVDs in my car so I can show it if I get stopped.""
However, Deacon insists he has noticed a change in the police force while filming the documentary, adding, ""I met police cadets aged 15 or 16 and I knew none of them were at all racist. They were joining the force to make a difference and to help the community.
""Slowly, the police are building up trust with communities - especially after last year's riots. The problem is it doesn't take much to damage that trust again.""