a famous US court case in 1925 in Dayton, Tennessee. A teacher, John Scopes, was put on trial because he taught Charles Darwin's theory of evolution, which was illegal under local law. The case was informally called the 'monkey trial'. The American Civil Liberties Union got Clarence Darrow to defend Scopes, and William Jennings Bryan helped to argue the case against him. Scopes was judged guilty but freed for technical reasons. The law was only changed in 1967.