Maurice Morton Milligan (November 23, 1884 – June 19, 1959), a U.S. Attorney for the Western District of Missouri, is most famous for the successful 1939 prosecution of Kansas City boss Tom Pendergast.
Born in Richmond, Missouri, he received his bachelors and law degrees from the University of Missouri. He practiced law, was Richmond city attorney, and then probate judge for Ray County, Missouri. Milligan was a federal prosecutor from 1934 to 1945. After toppling Pendergast, Milligan ran in 1940 for the U.S. Senate seat held by Harry S. Truman. He and Missouri Governor Lloyd C. Stark split the anti-Pendergast vote in the Democratic primary and Truman won. Truman had defeated Milligan's brother, Jacob "Tuck" Milligan, in the Democratic primary for Truman's first Senate term in 1934. Maurice Milligan began his assault on the Pendergast machine following the 1936 election and he got convictions on 259 of 278 defendants. Milligan's case against Pendergast centered on a $750,000 insurance payoff scam and failure to pay federal income taxes from 1927 to 1937. Pendergast ultimately pleaded guilty to two charges of income tax evasion and was fined $10,000 and sentenced to 15 months in federal prison. In 1948 Milligan wrote a book about his exploits: Missouri Waltz, The Inside Story of the Pendergast Machine by the Man Who Smashed It (ISBN 1-299-19592-X). He died in Kansas City, Missouri. He is interred in Sunny Slope Cemetery in Richmond, Missouri.