AMERICAN GANGSTER star RZA was taught to be a cop while filming the crime movie - by the same officers who chased him as a kid. The Wu-Tang Clan rapper turned the tables on his youth as a tearaway on the streets of New York to play a NYPD officer in the Ridley Scott-directed film. And he was stunned to recognise the faces of the officers recruited to show him the ropes. RZA - real name Robert Diggs - says, "As a kid in New York, I must have been chased by the cops every week. "On the set, Universal spared no expense. We had cops teaching cops. Some of those cops knew me. I actually became friends with them. I have a new respect for police."