Long after the Brown v. Board of Education decision, some states had not desegregated their schools because

In Brown v. Board of Education, the Supreme Court ruled that segregated public schools were unconstitutional. In a later ruling, it told schools to desegregate with “all deliberate speed” but did not set a firm deadline, which allowed some states to delay. So the best answer is “the Supreme Court had not set a deadline for doing so.”

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