Facts
- After the 2010 Census, Texas enacted a state senate redistricting plan using total census population as the apportionment base.
- The plan’s maximum deviation in total population across districts was 8.04%, within the generally accepted 10% range for state legislative plans.
- When measured by voter-based baselines (eligible or registered voters), the plan produced deviations exceeding 40%.
- Two Texas voters residing in districts with comparatively large eligible- and registered-voter populations alleged their votes were diluted relative to voters in districts with fewer eligible or registered voters.
- The plaintiffs sought an injunction requiring Texas to redraw districts to equalize voter population rather than total population.
Issues
- Whether the Equal Protection Clause’s one-person, one-vote requirement compels a state to equalize legislative districts by eligible or registered voters instead of total population.
- Whether a state violates equal protection by drawing state legislative districts on the basis of total census population despite substantial variation in voter-based measures across districts.
Decision
- The Supreme Court unanimously affirmed dismissal of the complaint for failure to state a claim.
- The Court held that a state may constitutionally draw legislative districts based on total population.
- The Court did not decide whether a state may choose to use a voter-based metric (such as eligible voters) in place of total population.
- Justice Thomas and Justice Alito concurred in the judgment, emphasizing the limited scope of the holding and cautioning against reading the Court’s reasoning as making total population mandatory.
Legal Principles
- The Equal Protection Clause permits states to comply with one-person, one-vote by apportioning state legislative districts using total census population.
- Constitutional history and post–Fourteenth Amendment practice support representational equality: elected officials represent all residents, including nonvoters such as children and noncitizens.
- One-person, one-vote precedents require substantially equal district populations, but do not establish that the Constitution requires equalization by any particular voter-based metric.
- Longstanding, uniform state reliance on decennial census total-population data supports the constitutional permissibility and administrability of total-population districting.
- The decision leaves open whether alternative apportionment bases (including voter-based measures) are constitutionally permissible in other circumstances.
Conclusion
The Court held that Texas did not violate equal protection by apportioning state senate districts using total population, rejecting a claimed constitutional right to districts equalized by eligible or registered voters while expressly reserving whether states may adopt voter-based apportionment metrics.