## Facts

- Arizona voters created the Arizona Independent Redistricting Commission (AIRC) by initiative to draw legislative districts after each census.
- After the 2010 census, AIRC adopted a plan for Arizona’s 30 state legislative districts.
- AIRC first drew districts close to equal population, then adjusted lines to address compactness/contiguity, communities of interest, and compliance with the Voting Rights Act (VRA), including maintaining or increasing minority “ability-to-elect” districts.
- The final plan produced a maximum population deviation of about 8.8% between the largest and smallest districts.
- Several voters challenged the plan, alleging AIRC intentionally underpopulated Democratic-leaning districts and overpopulated Republican-leaning districts to advantage Democrats, violating the Equal Protection Clause’s one-person, one-vote requirement.
- AIRC asserted that deviations were tied to good-faith efforts to satisfy Section 5 of the VRA (then applicable to Arizona) and obtain federal preclearance; the Department of Justice precleared the plan.
- A three-judge federal district court upheld the plan, finding the deviations justified by VRA compliance goals.

## Issues

1. Whether a state legislative redistricting plan with an overall population deviation under 10% violates one-person, one-vote when challengers allege the deviations were driven by partisan advantage.
2. Whether efforts to comply with Section 5 of the Voting Rights Act (including preserving minority ability-to-elect districts) constitute a legitimate state policy that can justify minor population deviations.

## Decision

- The Supreme Court unanimously affirmed the judgment upholding the plan.
- Because the overall deviation was under 10%, the plan was presumptively constitutional, and challengers bore the burden to show deviations predominantly resulted from illegitimate factors.
- The Court held the record supported the finding that deviations predominantly reflected good-faith VRA compliance efforts rather than partisan favoritism.
- The Court treated compliance with Section 5 (as it applied when the map was drawn) as a rational, legitimate redistricting objective that can justify minor deviations.
- The Court rejected arguments that later changes to Section 5’s coverage regime undermined the legitimacy of the Commission’s reliance on Section 5 at the time of redistricting.

## Legal Principles

- State legislative districting need not achieve perfect population equality; minor deviations are permissible when tied to legitimate state policies.
- An overall population deviation under 10% is generally presumptively valid; challengers must prove the deviations predominantly stem from illegitimate considerations.
- Partisan advantage, standing alone, does not justify departures from population equality, but challengers must show it predominated over lawful objectives to invalidate an under-10% plan.
- Good-faith compliance with the Voting Rights Act, including steps taken to obtain Section 5 preclearance and preserve minority ability-to-elect districts, is a legitimate justification for minor deviations.
- Appellate review of trial-level factual findings in redistricting cases is deferential; findings are upheld absent clear error.

## Conclusion

The Court upheld Arizona’s legislative map because its under-10% population deviations were presumptively constitutional and, on the trial record, were best explained by the Commission’s good-faith effort to comply with the Voting Rights Act rather than by a predominant partisan purpose.


Harris v. Ariz. Indep. Redistricting Comm’n, 578 U.S. 253 (2016)