Redistricting in Arizona

The U.S. state of Arizona, in common with the other U.S. states, must redraw its congressional and legislative districts every ten years to reflect changes in the state and national populations. Redistricting normally follows the completion of the United States Census, which is carried out by the federal government in years that end in 0; the most recent Census took place in 2010. Historically, Arizona's legislature has had control over the redistricting process. However, Proposition 106, passed in 2000, delegated the power to draw congressional and legislative boundaries to a bipartisan independent commission. The Arizona Independent Redistricting Commission (AIRC) comprises two Democrats, two Republicans, and one independent chair. County and local redistricting, which normally takes place along the same timeline as congressional and legislative redistricting, is carried out by the individual county and local governments rather than the AIRC.

Reapportionment of representatives between the states every ten years based on new census figures is required by Article I, Section 2 of the U.S. Constitution and Section 2 of the Fourteenth Amendment. The Constitution, Supreme Court jurisprudence and federal law allow significant latitude to the individual states to draw their congressional and legislative districts as they see fit, as long as each district contains roughly equivalent numbers of people (see Baker v. Carr, Wesberry v. Sanders, and Reynolds v. Sims) and provides for minority representation pursuant to the Voting Rights Act. While control over redrawing district lines has been in the hands of state legislators for most of American history, a number of states, including Arizona, have adopted independent or bipartisan commissions for redistricting purposes in the last twenty years.

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