This 1884 decision is the only nineteenth century case in which the Supreme Court allowed the federal government to enforce the Fifteenth Amendment by punishing private individuals for obstructing a citizen’s right to vote.
In Ex parte Yarbrough, also known as the Ku Klux Klan case, Jasper Yarbrough and his fellow Klansmen were convicted in federal court of using violence against an African American, Berry Saunders, to prevent him from voting in a federal election. The Supreme Court unanimously upheld the conviction. Justice Samuel F. Miller broadly interpreted the Fifteenth Amendment as a guarantee that a citizen must not be prevented from voting in federal elections because of his race. In James v. Bowman
Congressional power to enforce amendments
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