According to the ruler in placid versus Ferguson case what made the segregation acceptable

In the Plessy v. Ferguson case, the ruling established the legal doctrine of "separate but equal." According to the Supreme Court's ruling in 1896, segregation was deemed acceptable as long as the separate facilities provided to different racial groups were equal in quality. This meant that as long as the separate facilities provided to Black and White individuals were seen as equal in the eyes of the law, segregation was considered constitutional and permissible. This ruling upheld racial segregation in many public institutions, such as schools, transportation, and other public facilities, leading to widespread racial discrimination and inequality for decades.