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
Al Capone target him. His driver was found tortured and murdered, and there was an attempt on Weiss's life in the Chicago Loop. On September 20, 1926, the North Side Gang used a ploy outside the Capone headquarters at the Hawthorne Inn, aimed at drawing him to the windows. Gunmen in several cars then opened fire with Thompson submachine guns and shotguns at the windows of the first-floor restaurant. Capone was unhurt and called for a truce, but the negotiations fell through. Three weeks later, Weiss was killed outside the former O'Banion flower shop North Side headquarters. The owner of Hawthorne's restaurant