In the 1896 case of Plessy v. Ferguson, the Supreme Court upheld the constitutionality of racial segregation under the "separate but equal" doctrine. The case originated when Homer Plessy, a man of mixed race, was arrested for sitting in a "whites only" railroad car in Louisiana, violating state segregation laws. The Supreme Court ruled in a 7-1 decision that the segregation of races in public facilities was legal, provided that the separate facilities were equal in quality.
The majority opinion, delivered by Justice Henry Billings Brown, stated that the law did not imply the inferiority of African Americans and that social inequalities were not a violation of the 14th Amendment's Equal Protection Clause. This ruling effectively legitimized state-sponsored segregation for many decades and became a legal foundation for the Jim Crow laws that enforced racial segregation in the Southern United States. The "separate but equal" doctrine remained in place until it was ultimately overturned by the Supreme Court in the 1954 case Brown v. Board of Education.