Mahan v. Howell

Electoral districts were supposed to be as equal in population as possible. But Mahan v. Howell established two qualifications to that principle: that states could be more flexible in creating state legislative districts than in creating U.S. congressional districts, and that preserving such existing political units as counties and cities was a valid consideration in drawing state electoral districts.

"One person, one vote"--that principle is one of the basic slogans of U.S. democracy. It is also one of the reasons that electoral districts are constantly being redrawn. An electoral district is the unit within which a person votes. To elect U.S. Representatives, a person votes in a congressional district. To elect members of the state legislature, a person votes in a legislative district. Ideally, each type of electoral district has the same number of people in it.

In the 1960s, civil rights leaders claimed that African Americans were crowded into big electoral districts, while white Americans were divided up into smaller districts. As a result, white people had the chance to elect more than their fair share of representatives to state and national office. Many states were ordered to re-draw their electoral districts in order to make them more fair.