Kelly was a small-time bootlegger until he met his wife, Kathryn, who introduced him to friends of hers, with whom he kidnapped Charles F. Urschel, an Oklahoma City oilman, on July 22, 1933. D.O.I. agents captured Kelly on September 26, 1933, and sentenced him to life in prison, 17 of which he spent on Alcatraz. In 1951 he was transferred to Leavenworth, where he died of a heart attack.