578 U.S. 74 (2016)
Following the 2010 decennial census, Texas redrew its State Senate districts on the basis of total population drawn from census data.1 The resulting permanent map produced a maximum total-population deviation of 8.04 percent, well within the 10 percent range that presumptively satisfies one-person, one-vote requirements.2 Measured by eligible or registered voters, however, the same map generated a maximum deviation exceeding 40 percent.3
Appellants Sue Evenwel and Edward Pfenninger live in Senate districts one and four, which have especially large eligible- and registered-voter populations.4 They brought suit in the United States District Court for the Western District of Texas.5 They named the Governor and Secretary of State as defendants.6 Appellants claimed that total-population apportionment dilutes their voting power in violation of the Equal Protection Clause.7 They requested an injunction requiring districts of equal voter-eligible population.8
At the time of the redistricting, Texas remained subject to preclearance under the Voting Rights Act.9 This prompted the District Court to draw an interim map used in the 2012 elections.10 The legislature later enacted that map as the permanent plan.11 A three-judge district court dismissed the complaint for failure to state a claim.12 The Supreme Court noted probable jurisdiction and affirmed the dismissal.13
Whether the Equal Protection Clause requires state and local legislative districts to be apportioned on the basis of voter-eligible population rather than total population?14
As constitutional history, precedent, and practice demonstrate, a State or locality may draw its legislative districts based on total population.15
No. Constitutional history shows the Framers endorsed total-population apportionment for House seats under the Great Compromise and retained that baseline in the Fourteenth Amendment after rejecting voter-population proposals.16 Precedent from Reynolds v. Sims onward has evaluated one-person, one-vote compliance using total-population figures, and settled practice confirms that all fifty States use census total-population data for legislative districts.17 Applying the rule to the established facts, Texas drew its Senate map after the 2010 census using total-population figures, producing an 8.04 percent maximum deviation that falls safely inside the presumptively permissible 10 percent range.18 The same map produces more than 40 percent deviation when measured by eligible or registered voters.19
Appellants Evenwel and Pfenninger, who reside in Senate districts one and four with especially large eligible-voter populations, therefore cannot prevail on their claim that the Equal Protection Clause mandates equalization of voter-eligible population.20
The Equal Protection Clause permits a State to apportion its legislative districts on the basis of total population rather than voter-eligible population.21
Related opinions on this issue
Justice Thomas concurs in the judgment but writes separately to emphasize that the Court has never supplied a sound basis for the one-person, one-vote principle itself.22 He maintains that the Constitution leaves States wide latitude to choose among total population, eligible voters, or other nondiscriminatory bases when apportioning their own districts.23 In his view the majority errs by attempting to extract a single theory of representation from constitutional history; the choice among competing theories properly belongs to the people of each State rather than to this Court.24
Joined by Justice Thomas (except As To Part Iii-b)
Justice Alito concurs in the judgment, agreeing that practical considerations and precedent permit Texas to use total population.25 He refuses, however, to endorse the argument that the constitutional formula for allocating House seats among the States compels total-population districting inside a State.26 That formula, he explains, originated in raw political compromises over power between large and small States and between free and slave States, not in any abstract theory of representational equality.27
He would therefore decide only that Texas acted permissibly in the case before the Court.28