The history of racial segregation in the United States provides examples of each:
1. The Supreme Court decision in Plessy v. Ferguson legalized segregation in transportation and other public facilities, so long as the facilities were "separate but equal"; as history shows, facilities were always separate, but rarely equal.
2. In many areas of the United States, segregation was maintained through local custom. Neighborhoods, stores, and restaurants did not allow equal access; although it was not necessarily defined by law, it was just as rigidly enforced.