Redistricting is the process of drawing boundaries for electoral and political districts in the U.S. and is usually done every ten years after the census. The U.S. Constitution requires each Representative in Congress represent an equal number of citizens and mandates a census to determine the number of citizens and apportion seats to each state. Here is an overview of the constitutional requirements, redistricting practices and the problem of gerrymandering.
Apportionment required by the Constitution and conducted by the Census Bureau
The U.S. Constitution (in Article I, Section 2) requires that Representatives be apportioned among the several states according to their respective numbers and specifies that there be at least one Representative for every 30,000 citizens (and each state must have at least one Representative). Every ten years, the Census Bureau conducts a nationwide census and informs each state how many seats it will have in the U.S. House of Representatives for the next decade.
Redistricting procedures vary by state
Individual states have the responsibility of drawing legislative boundaries for congressional districts as well as for state legislative districts. In most states, the state legislature redistricts seats, usually subject to concurrence by the state governor. A few conduct redistricting through an independent or bipartisan commission in order to minimize the impact of partisan or legislative politics. A handful allow an independent commission to propose redistricting plans subject to approval by the state legislature.
Seven states have only a single representative due to low population: Alaska, Delaware, Montana, North Dakota, South Dakota, Vermont and Wyoming. The National Conference of State Legislatures maintains an excellent resource page on state redistricting plans and processes.
Each state maintains standards for creating electoral districts. Beyond equalizing the population of districts and complying with other federal requirements, criteria may include creating compact, contiguous districts; keeping political units and communities within a single district; and avoiding the drawing of boundaries for purposes of partisan advantage or incumbent protection.
State and federal court systems become involved in resolving disputes over redistricting when the process cannot be completed in a timely manner or where there are allegations of gerrymandering or racial discrimination.
Gerrymandering
Gerrymandering is the practice of dividing election districts to give special advantages to one group and usually to give one political party an electoral majority in a large number of districts while concentrating the opposition’s voting strength in the fewest districts possible. This is done by manipulating the geographic boundaries of electoral districts to create partisan, incumbent-protected districts.
Gerrymandering may be used to skew electoral results for (or against) a particular party or a political, racial, linguistic, religious, or class group.
The Voting Rights Act prohibits voting practices and procedures including redistricting plans that discriminate on the basis of race, color or language minority group. The Act also prohibits 16 states, either in full or in part, from making changes affecting voting like redistricting plans without establishing that the change does not have a discriminatory purpose or discriminatory effect. The U.S. Attorney General or the U.S. District Court for the District of Columbia may approve the jurisdictions’ voting plans.