During much of the twentieth century, segregation was legal in Southern schools. Advocates of segregation supported their position by using the "separate but equal" concept.
Prior to 1951, the NAACP focused its energy on slowing chipping away at pro-segregation legislation. In 1951, Thurgood Marshall, a leading member of the NAACP, began coordinating the organization's efforts to directly challenge the seperate-but-equal doctrine.
Marshall's goal was to overturn the Plessy v. Ferguson decision and the constitutionality of segregation itself, using five different law suits. One of these argued the case of Oliver Brown of Topeka, Kansas, who wanted to overturn a state law permitting cities to maintain segregated schools.
The Supreme Court heard Brown's argument in the case of Brown v. Board of Education. On May 17, 1954, Chief Justice Warren read the Court's unanimous decision, which said that segregation based on race deprives children of the minority group. It ruled that the doctine of separate but equal had no place in the field of public education.
The ruling of the trial was a momentous and clear constitutional ruling. The Court still left desegregation to local school boards, which limited the ruling's effectiveness.