On June 29, 2015, the Supreme Court issued its ruling in Arizona State Legislature v. Arizona Independent Redistricting Commission. In a 5-4 decision, the Court affirmed the district court's decision, finding that the redistricting commission created by Arizona’s voters via ballot initiative in 2000 does not violate the U.S. Constitution’s Elections Clause.
The case challenged a state constitutional amendment adopted in 2000 by Arizona voters which created a politically neutral commission drawing new boundaries for the state’s congressional districts every ten years. Before the amendment, the state legislature, as in many states, had been responsible for setting and adjusting district lines.
The Commission drew district boundaries in 2001 and again in 2011. After the 2011 redistricting, however, the Republican-controlled state legislature sued the Commission, arguing that use of the Commission to draw maps violated the U.S. Constitution’s Elections Clause. At issue was a portion of the Elections Clause that provides that, the “times, places and manner of holding elections for Senators and Representatives, shall be prescribed in each state by the legislature thereof.” Because redistricting traditionally has been construed to fall within the ambit of “manner” of holding elections, Arizona argued that the strict language of the clause meant that congressional districts can be drawn only by state legislatures.
A panel of three federal judges rejected the challenge in a 2-1 decision, holding that the use of the term “legislature” in the Elections Clause should be read to refer to the entirety of a state’s legislative process, including ballot initiatives passed by the voters.
Affirming the district court’s decision, the Supreme Court also rejected the Arizona legislature’s “wooden” interpretation of the Election Clause. In doing so, the Court preserved a valuable tool used by citizens across the country to reform redistricting practices.
Had the Court reached the opposition conclusion, it could have had far reaching ramifications, throwing into doubt a number of longstanding state practices across the country. A growing number of states in recent years, including California, have given independent commissions the power to set the boundaries of their congressional districts. In fact, almost half of the states now use redistricting commissions in some form, including as a backup if the legislature is unable to pass a redistricting plan. Efforts to adopt similar sorts of reforms are currently underway in Illinois, Ohio, and South Dakota – with Arizona and California frequently serving as models for proposed reforms. The decision also could have thrown in doubt dozens of other election laws  ranging from Washington State’s top two primary to Mississippi’s voter identification law that were enacted through ballot initiative.
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