What doctrine was upheld in Plessy v. Ferguson?

The doctrine upheld in Plessy v. Ferguson was "separate but equal." This landmark Supreme Court case, decided in 1896, validated state laws that established racial segregation in public facilities, asserting that as long as the separate facilities for the races were equal, segregation did not violate the Equal Protection Clause of the 14th Amendment.

The ruling effectively provided a legal foundation for the continuation and expansion of racial segregation in various aspects of public life, including education, transportation, and other public accommodations. This doctrine had significant implications for the civil rights movement, as it legitimized discriminatory practices and reinforced systemic racism in the United States.

The other options highlight important concepts in American legal and civil rights history, but they were not the focus of the Plessy v. Ferguson decision. For instance, equal protection under the law is a broader principle established by the 14th Amendment, universal suffrage pertains to voting rights, and affirmative action involves policies aimed at increasing opportunities for historically marginalized groups. However, none of these concepts were the central issue being addressed in the Plessy case. Thus, the importance of "separate but equal" lies in its historical context in reinforcing segregation laws until it was eventually struck down by the Supreme Court in