Plessy v. Ferguson, case in which the U.S. Supreme Court, on May 18, 1896, by a seven-to-one majority (one justice did not participate), advanced the controversial “separate but equal” doctrine for assessing the constitutionality of racial segregation laws. Plessy v. Ferguson was the first major inquiry into the meaning of the Fourteenth Amendment’s (1868) equal-protection clause, which prohibits the states from denying “equal protection of the laws” to any person within their jurisdictions. Although the majority opinion did not contain the phrase “separate but equal,” it gave constitutional sanction to laws designed to achieve racial segregation by means of separate and supposedly equal public facilities and services for African Americans and whites. It served as a controlling judicial precedent until it was overturned by the Supreme Court in Brown v. Board of Education of Topeka (1954).

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