On April 20, 2016, the Supreme Court decided Harris v. Arizona Independent Redistricting Commission, No. 14-232, holding that a redistricting plan is not unconstitutional where the maximum population deviation between the largest and the smallest district is less than 10 percent and other evidence does not demonstrate that the plan likely was created through reliance on impermissible factors.
The Arizona Constitution provides for an independent redistricting commission that consists of two Democrats, two Republicans, and one independent. The Commission members are selected decennially. Following each decennial census, the Commission redraws Arizona’s legislative districts. First, it draws a grid across Arizona to create districts of equal population. Then, it adjusts the grid, “to the extent practicable,” to further the interests of (a) population equality, (b) geographic compactness and continuity, (c) communities of interest, (d) locality boundaries, (e) visible geographic features, including undivided tracts, and (f) political competitiveness, to the extent that this interest does not detract from the others. Finally, the Commission adjusts the resulting boundaries as necessary to comply with the United States Constitution and the Federal Voting Rights Act, 42 U.S.C. §§ 1973, et seq.
The Voting Rights Act contains a non-retrogression requirement: it “forbids the use of new reapportionment plans that would lead to a retrogression in the position of racial minorities with respect to their effective exercise of the electoral franchise.” A plan is impermissibly retrogressive if it “diminishes the number of districts in which minority groups can elect their preferred candidates of choice” (“ability-to-elect districts”) as compared to the prior “benchmark” plan. The Federal Department of Justice does not identify for States the number of ability-to-elect districts in a benchmark plan; nor does the Justice Department explain how it will calculate the number of ability-to-elect districts in a newly proposed plan. But a State may confirm that it has satisfied the Voting Rights Act’s non-retrogression requirement if it submits the proposed plan to the Justice Department and receives no objection within 60 days.
In 2010, Arizona’s Commission undertook its redistricting process. After it gridded Arizona into equal districts, the maximum population deviation among districts was 4.07 percent. Because the benchmark plan effected 10 ability-to-elect districts, the Commission sought to ensure that the 2010 plan also established ten ability-to-elect districts. After completing the rest of its iterative process, and believing the plan created 10 ability-to-elect districts, the Commission tentatively approved the draft 2010 plan in October 2011 and published it for public comment.
Concurrently, a Commission statistician suggested that the Justice Department might disagree about the number of ability-to-elect districts in the proposed plan. The Commission thereafter adopted several changes to the proposed plan in an effort to ensure that the 2010 plan contained 10 ability-to-elect districts. The Commission adopted the noncontroversial changes unanimously, but its partisan members disagreed about a boundary change between two of Arizona’s more-partisan districts. After the Commission’s Voting Rights Act specialist suggested that changes to this debated boundary could effect an 11th ability-to-elect district that would “unquestionably enhance” the chances that the Justice Department would preclear the plan, the Commission’s independent member supported the changes. The Commission subsequently adopted the plan by a 3-2 vote, with its Republican-appointed members dissenting. The final plan’s total population deviation among districts was 8.8 percent. The Justice Department precleared the plan on April 26, 2012.
Plaintiffs challenged the 2010 plan on Fourteenth Amendment Equal Protection Clause grounds and argued that “the plan reflects unreasonable use of partisan considerations.” The Court held that
[b]ecause the maximum population deviation between the largest and the smallest district is less than 10 percent, the [plaintiffs] cannot simply rely upon the numbers to show that the plan violates the Constitution.” The Court dismissed as unsupported by the record plaintiffs’ argument that discrepancies in under- and over-population between Democratic and Republican districts supported the plaintiffs’ claim. The Court concluded that the plaintiffs failed to show that the 2010 plan’s deviations and boundary shapes more likely than not resulted from the Commission’s use of illegitimate factors. Finally, the Court held that Shelby County v. Holder, 570 U.S. ___ (2013) was not relevant to its analysis because the Court issued Shelby County after the Commission drafted the 2010 plan.
Justice Breyer delivered the unanimous opinion of the Court.