The fourteenth amendment says, " no state to any person within it's jurdiction the equal protection of the law." how did the supreme court expand this protection in the 1950s?

The amendment broadens the definition of national citizenship, which overrides the decision of Dred Scott v. Sandford (1857), which excluded slaves and their descendants, from enjoying constitutional rights. This amendment requires states to provide equal protection before the law to all people within their jurisdictions. The importance of the Fourteenth Amendment was exemplified when it was interpreted to prohibit racial segregation in public schools in the Brown v. Board of Education