Al Capone Mabel Walker Willebrandt recognized that mob figures publicly led lavish lifestyles yet never filed tax returns, and thus could be convicted of tax evasion without requiring hard evidence to get testimony about their other crimes. She tested this approach by prosecuting a South Carolina bootlegger. In 1927, the Supreme Court ruled in "United States v. Sullivan" that illegally earned income was subject to income tax; Justice Oliver Wendell Holmes Jr. rejected the argument that the Fifth Amendment protected criminals from reporting illegal income. The IRS special investigation unit chose Frank J. Wilson to investigate Capone, with the focus on his
Capone (film) recognize Nitti, instead thinking that he is an FBI agent. Nitti's bodyguard tells Nitti that people said that Capone used to be a smart man, but Nitti – who had shown his ambition and loyalty throughout the movie – finally disregards this and expresses his true feelings about Capone, saying that Capone was stupid and forgetful, and only cared about killing people. As the two of them leave, Capone continues to lose his mind until he dies a year later. Screenwriter Howard Browne had written about Al Capone a number of times previously, including "Seven Against the Wall" for "Playhouse