The Scopes Trial—formally known as The State of Tennessee v. John Thomas Scopes and informally known as the Scopes Monkey Trial—was a landmark American legal case in 1925 in which high school science teacher, John Scopes, was accused of violating Tennessee's Butler Act

Butler Act

The Butler Act was a 1925 Tennessee law prohibiting public school teachers from denying the Biblical account of man’s origin. It was enacted as Tennessee Code Annotated Title 49 Section 1922...

 which made it unlawful to teach evolution

Evolution

Evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organisation, including species, individual organisms and molecules such as DNA and proteins.Life on Earth...

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Scopes was found guilty, but the verdict was overturned on a technicality and he went free.