School districts have had to grapple with two different kinds of segregation: de jure, or enforced by law, and de facto, or not enforced by law but still existent. The Supreme Court's Brown v. Board of Education decision declared de jure segregation, prevalent in the South, unconstitutional, but it said nothing about de facto segregation, prevalent in the North.
De facto segregation existed mainly because of housing patterns. For a variety of reasons, middle-class whites started to leave America's cities, opting for the suburbs. At the same time, many blacks started to move into the cities. This resulted in primarily black cities, which led to primarily black schools. Also, blacks tended to live in primarily black neighborhoods and whites tended to live in primarily white neighborhoods; because most schools educated students from the immediate neighborhood, this led to segregated schools, even though no laws required segregation. Segregation in the North became very widespread; "by the 1970's, public schools in the North were more segregated than those in the South," and in 1971, "the Supreme Court...sustained busing as a lawful remedy for unconstitutional segregation." [1] Public sentiment favored integration but did not favor busing as a means of attaining it. Despite this, many Northern school boards went ahead with plans to integrate public schools via busing.