<Li> The first, on June 5, 1917, was for all men between the ages of 21 and 30 . </Li> <Li> The second, on June 5, 1918, registered those who attained age 21 after June 5, 1917 . A supplemental registration, included in the second registration, was held on August 24, 1918, for those becoming 21 years old after June 5, 1918 . </Li> <Li> The third registration was held on September 12, 1918, for men age 18 through 45 . </Li> <P> The Selective Service Act was upheld by the United States Supreme Court in the Selective Draft Law Cases, 245 U.S. 366 (1918). The Solicitor General's argument, and the court's opinion, were based primarily on Kneedler v. Lane, 45 Pa. 238, 252 (1863), and Vattel's 1758 treatise The Law of Nations . </P>

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