Congressional redistricting

Redistricting is the process of drawing United States electoral district boundaries.

In 32 states, the state legislature has primary responsibility for creating a redistricting plan, in many cases subject to approval by the state governor. To reduce the role that legislative politics might play, seven states (Arizona, California, Hawaii, Idaho, Montana, New Jersey and Washington) determine congressional redistricting by an independent or bipartisan redistricting commission. Four states, Florida, Iowa, Maine, and New York give independent bodies authority to propose redistricting plans, but preserve the role of legislatures to approve them. Seven states have only a single representative for the entire state because of their low populations; these are Alaska, Delaware, Montana, North Dakota, South Dakota, Vermont and Wyoming.

State constitutions and laws also mandate which body has responsibility over drawing the state legislature boundaries. In addition, those municipal governments that are elected on a district basis (as opposed to at-large) also redistrict.

Each state has its own standards for creating Congressional and legislative districts. In addition to equalizing the population of districts and complying with Federal requirements, criteria may include attempting to create compact, contiguous districts, trying to keep political units and communities within a single district, and avoiding the drawing of boundaries for purposes of partisan advantage or incumbent protection. In the states where the legislature (or another body where a partisan majority is possible) is in charge of redistricting, the possibility of gerrymandering (the deliberate manipulation of political boundaries for electoral advantage, usually of incumbents or a specific political party) often makes the process very politically contentious, especially when the majorities of the two houses of the legislature, or the legislature and the governor, are from different parties. The state and federal court systems are often involved in resolving disputes over Congressional and legislative redistricting when gridlock prevents redistricting in a timely manner. In addition, the losers to an adopted redistricting plan often challenge it in state and federal courts. Justice Department approval (which is known as pre clearance) was formerly required under Section 5 of the Voting Rights Act of 1965 in certain states that have had a history of racial barriers to voting.

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