Key Amendment in Brown v. Board of Education

In the landmark Supreme Court case Brown v. Board of Education (1954), the court ruled that segregation in public schools was unconstitutional. This case overturned the precedent set by Plessy v. Ferguson (1896), which upheld the constitutionality of racial segregation under the 'separate but equal' doctrine. The ruling was significant in advancing civil rights in the United States. Which amendment did the Court primarily rely on in its decision to rule against school segregation?