The Fourteenth Amendment became the law of the land in 1868. However, for most of the late 19th century and the first half of the 20th, racial discrimination was mandated by law in many states and the Supreme Court did not strike it down until 1954's Brown v. Board of Education. What doctrines did the Court use to justify letting this discrimination stand before Brown? What finally led the Court to enforce the Fourteenth Amendment and strike down so-called Jim Crow laws