Al Capone
Al Capone was a powerful and influential gangster in Chicago during the Prohibition Era. He hired Tom Dekker to investigate a speakeasy called "Doc's Place". It was run by the Seventh Doctor, who was trying to stop Agonal's evil manipulation of Capone and others. (PROSE: Blood Harvest)
He was imprisoned in Alcatraz (PROSE: Players) for tax-related transgressions. when Romana and Narvin suggested a technicality regarding taxes to Livia as a means by which she could resign during wartime while maintaining her reputation, Romana commented that it was how they got Al Capone. Narvin did not understand the reference, which disappointed Romana, and she thought that Ace would have understood. (AUDIO: Desperate Measures)
The Eleventh Doctor was uncertain if it had been Al Capone or Genghis Khan who had told him that villains wanted records of exactly how bad they'd been. (PROSE: Borrowed Time)