On May 18, 1896, the U.S. Supreme Court ruled 7-1 in Plessy v. Ferguson that racial segregation on railroads or similar public places was constitutional, that stated as long as the segregated facilities were equal in quality forging the “separate but equal” doctrine,
The decision legitimized the many state laws re-establishing racial segregation that had been passed in the American South after the end of the Reconstruction Era(1865–1877). This remained in place until 1954.
In his dissent, Justice John Marshall Harlan wrote, “Our constitution is color-blind, and neither knows nor tolerates classes among citizens. In respect of civil rights, all citizens are equal before the law.”

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https://en.wikipedia.org/wiki/Plessy_v._Ferguson