Evenwel, et al. v. Abbott, et al.

LII note: The U.S. Supreme Court has now decided Evenwel, et al. v. Abbott, et al..


Does the “one-person, one-vote” principle of the Fourteenth Amendment’s Equal Protection Clause permit states to draw their legislative districts on the basis of total population, or does it require States to use voter population?

Oral argument: 
December 8, 2015

In this case, the Supreme Court will decide the Fourteenth Amendment’s “one-person, one-vote” principle requires states to apportion eligible voters equally across districts. The Texas Constitution requires that the State legislature reapportion its legislative districts after each federal decennial census. In 2013, Texas adopted a new redistricting plan (“Plan S172”). Texas drew its senatorial districts based only on total population. Sue Evenwel is a registered Texas voter. Evenwel argues that the one-person, one-vote principle requires states to divide their districts so that they each comprise a substantially equal number of eligible voters.Texas Governor Greg Abbott contends that the Constitution does not require states to utilize any specific measure, and thus they are free to equalize districts on the basis of total population. The Court’s decision could affect the voting power of eligible voters, and the method and amount of data collection states must engage in to constitutionally apportion voting districts.

Questions as Framed for the Court by the Parties 

Did the three-judge district court correctly hold that the “one-person, one-vote” principle under the Equal Protection Clause allows States to use total population, and does not require States to use voter population, when apportioning state legislative districts?


After each federal decennial census, the Texas Constitution requires that the State legislature reapportion its legislative districts. To that end, Texas must distribute members of the House of Representatives to each county according to its the total population, by using a ratio of state population to number of House members. However, the Texas Constitution does not say how senatorial districts should be apportioned. The Texas Constitution once mandated apportionment “according to the number of qualified electors,” but the provision was removed by constitutional amendment in 2001. Today, the Texas Constitution requires “contiguous” senatorial districts; “each district [is] entitled to elect one Senator.”

In 2013, Texas adopted a new redistricting plan (“Plan S172”). Texas drew its senatorial districts based only on total population. Sue Evenwel is a Texas citizen and registered voter. In April 2014, Evenwel filed suit in the U.S. District Court for the Western District of Texas against then-Governor Rick Perry and Secretary of State Nandita Berry, alleging that Plan S172 violates the “one-person, one-vote” principle of the Equal Protection Clause. Evenwel alleged that Plan S172 created substantially large disparities in the number of eligible voters residing in each district. Evenwel argued that the Equal Protection Clause requires Texas to apportion districts “to equalize both total population and voter population.”.

The district court dismissed the case. The court found that Evenwel did not show that Plan S172 “fail[ed] to achieve ‘substantial equality of population’—what [Evenwel] refer[ed] to as the ‘one-person, one-vote’ principle.” The court explained that “mathematical equality is not necessary,” and that “minor deviations, defined as ‘a maximum population deviation under 10%’” are permissible. Although the Supreme Court has relied on total population “as the metric of comparison,” the district court noted that the Court has not mandated the use of total population or any other metric. Relying on the Court’s decision in Burns v. Richardson, 384 U.S. 73 (1966), Evenwell alleged that Texas needed to achieve equality of voter population. However, the district court found that the Court in Burns did not endorse voter population as a required metric. Also relying on Burns, the district court concluded that decisions on how to most appropriately measure population are best left to the states, and found no constitutional violations in Texas’s redistricting plan. Furthermore, the district court found that Evenwel’s claims that Texas must employ a particular metric involved “choices about the nature of representation” that it could not resolve, and thus constituted a judicially unreviewable political question.

Pursuant to 28 U.S.C. 2284, Evenwel appealed directly to the Supreme Court, and the Court noted probable jurisdiction on May 26, 2015. While this action was pending, Greg Abbott succeeded Rick Perry as Governor of Texas and assumed his role as appellee.


Evenwel argues that the one-person, one-vote principle guarantees each individual’s a vote of equal weight, and that using voter population as the apportion base for legislative districts is the only way to protect that right. But Abbott argues that the Court’s Equal Protection Clause jurisprudence permits the States to draw districts using total population.


Evenwel relies primarily on two Supreme Court cases, Reynolds v. Sims and Burns v. Richardson, to argue that Texas must equalize voter population across its districts. Evenwel maintains that the Court, in a line of cases ending with Reynolds v. Sims, 377 U.S. 533 (1964), focused on the constitutional rights of eligible voters to determine whether an apportionment basis was constitutional. Specifically, Evenwel explains that the Court in Reynolds focused on political equality amongst eligible voters, reasoning that the Constitution protects “the right of all qualified citizens to vote.” Evenwel argues that the Court held that an apportion system is unconstitutional if an individual’s vote is worth substantially less than votes cast “in other parts of the State.” Evenwel concedes that total population may serve as an acceptable apportionment base when it also closely reflects the eligible voter population, but contends that this does not apply to Plan S172, because the Texas districts do not contain relatively equal numbers of eligible voters.

Contrary to Abbot, Evenwel argues that Burns v. Richardson, 384 U.S. 73 (1966), did not foreclose the Court from reviewing Texas’ apportionment method. Evewel explains that the Burns Court “express[ed] concern” about using eligible voters as an apportionment basis, “because it ‘depends . . . upon the extent of political activity of those eligible to register and vote.’” But Evenwel contends that the Court “carefully left open” the question of whether total population or voter base was a more appropriate measure. Furthermore, Evenwel rejects Abbotts’ argument that the apportionment of seats in the U.S. House of Representatives by total population shows that states may also use total population to apportion their districts. Rather, Evenwel argues that the Court has consistently rejected this “federal analogy” argument.

Abbott argues that Burns does not require states “to apportion legislative seats based on some [specific] measure of voter population” to satisfy the Equal Protection Clause. Rather, Abbott contends that Burns interpreted the Equal Protection Clause as leaving apportionment definitions to the States, and thus the Court should respect a state’s choice of apportionment base unless it “arbitrar[ily], irrational[ly], or invidious[ly]” “exclude[s] a certain population.” Abbott explains that Burns “identifies two generally permissible” apportionment bases—total population and citizen population—but does not endorse either one over the other. Although the Burns Court permitted voter-registration population as an apportionment base, Abbott asserts that this decision was made “because of . . . [the] unique circumstances” of Hawaii (the state in question) and not “because it led to the same place as apportionment based on eligible voters.” Accordingly, Abbott argues that the use of total population as an apportionment base is constitutional. Moreover, Abbott claims the Court’s precedent does not “assume[] congruence between total population and voter population.” Rather, Abbott argues that the Court “consistently distinguished between residents, citizens, and voters,” and that it looked to “total population as a measure of equal apportionment of state legislative districts” in several other cases.

Abbot explains that Evenwel mischaracterizes his arguments as a federal analogy. Rather, Abbott contends that section two of the Fourteenth Amendment purposefully adopts the notion that “total-population equality [is] a permissible method of apportionment.” Abbott asserts that the Fourteenth Amendment’s legislative history shows that the Framers of the Amendment never intended for eligible voter population to serve as an apportionment base for state legislative districts.


Under the one-person, one vote framework, Evenwel contends that states must satisfy two elements: (1) states, in good faith, must try to equally apportion voter population across districts; and (2) the voter population deviation between districts should be less than 10 percent. Evenwel explains that redistricting plans are prima facie discriminatory if deviation exceeds 10 percent, compared to a hypothetical district in which the apportionment base is perfectly divided. Thus, Evenwel claims that her challenge can prevail by showing such deviation, and that there is no need to show any further invidious discrimination. Evenwel believes that the deviations in Plan S172 are so large—ranging from 40.08 percent to 49.23 percent—that the plan should be per se unconstitutional.

But Abbott maintains that the Court has clearly held that challenges under the one-person, one-vote doctrine must demonstrate invidious vote dilution. Abbott points to Whitcomb v. Chavis, 403 U.S. 124 (1971), and Reynolds, which held, Abbott claims, that “unconstitutional vote dilution [claims] require[] a showing of invidious discrimination.” To satisfy this requirement, Abbott contends Evenwel must “show either that the reapportionment was irrational or made with the purpose of diluting votes.” Abbott maintains that “a claim of mere disparate impact” is not sufficient. And Abbott argues that, under Mahan v. Howell, 410 U.S. 315 (1973), purposeful discrimination cannot be shown where the state made “an honest and good faith effort to equalize population among legislative districts.” Abbott argues Texas made a good faith effort to equalize population among districts by using a reliable measure of total population. As discussed, Abbott maintains that the Court does not require states to use any particular apportionment base, and that the Court has blessed plans that seek population equality.


The Supreme Court will determine whether Plan S172 violates the Equal Protection Clause by diluting the voting power of eligible voters in Texas. Evenwel argues that the Fourteenth Amendment requires Texas to equalize the number of eligible voters in each district. But Abbot contends that states may choose whether to apportion their districts based upon the total population, citizen population, or voting-eligible population. The Court’s decision could affect the voting power of eligible voters, and the method and amount of data collection states must engage in to constitutionally apportion voting districts.


Evenwel contends that protecting the voting power of each citizen is deeply rooted in the Court’s precedent, and in the republican and federalist philosophies that guided the Framers’ construction of the Constitution. The Cato Institute argues that apportioning state voting districts by population does not further these deeply rooted principles. Some argue that the states should be able to mirror the federal government, which apportions each state’s “seats in the House of Representations by total population rather than voter population.” But the Cato Institute maintains that this “federal analogy” is irrelevant to drawing state-level voting districts. The Cato Institute argues that the method of House apportionment was intended to preserve the balance of power between the states and the federal government, by ensuring that states could not artificially inflate their power in Congress. The Cato Institute explains that if the states were apportioned seats in Congress by their number of eligible voters, and the states controlled who was an “eligible voter,” states would be incentivized to extend voting rights “to gain an advantage in national elections.” But if extended to the state level, the Cato Institute maintains that the analogy falls apart, because “[n]o state allows different counties to define the franchise [i.e., voter eligibility] differently for state legislative elections.”

By relying on total population, Evenwel worries that Texas’s redistricting plan artificially “dilutes” the relative weight of some citizens’ votes by creating districts that substantially differ in the number of eligible voters. The Mountain States Legal Foundation contends that this disparity effectively discriminates against some voters on the basis of geography, which the Court has declared states cannot do. Project 21 claims that voter-based apportionment would enhance the representational rights of underrepresented minorities by giving those communities greater electoral power.

But Abbott and supporting amici believe that a focus on citizens’ voting equality misinterprets the principles of republicanism underlying the Constitution. The American Civil Liberties Union (“ACLU”) reasons that each state has an obligation to provide its citizens a republican form of government under the Constitution, and contends that a government, to be republican, must represent “all the people.” The ACLU asserts that “an apportionment system based on total population” is one way of ensuring equal representation, because it protects the interests of “all the people,” and not just registered voters.The ACLU argues that apportionment based upon total population incentivizes elected officials to consider the broader interests of their communities and thus protects the “universal and equal representation” of all people, not just voters. Accordingly, the cities of Los Angeles and New York fear that equalizing only eligible voters within districts would unjustifiably diminish the political, social, and economic interests of immigrants, children, and disenfranchised Americans. Specific to Texas, the Texas Senate Hispanic Caucus cautions that a focus on citizenship will cause a fundamental shift in politics by minimizing the voices of “growing and diverse communities” in South and West Texas.


Evenwel contends that Texas possesses ample data to apportion its legislative districts on the basis of eligible-voter population. Evenwel notes that the American Community Survey (“ACS”) annually estimates the distribution of voting-age citizens across the country and that this data is sufficiently precise for use in reapportionment. Additionally, the American Civil Rights Union (“ACRU”) argues that citizenship based metrics correspond with the federal government’s application of voting rights laws. Therefore, Evenwel believes that requiring Texas to equalize voter population across legislative districts would not impose an additional burden.

Nevertheless, Abbot contends that voter apportionment is plainly impracticable, “[t]o the extent [Evenwel] argue[s] that Texas must equalize both total and voter population.” Former Directors of the U.S. Census Bureau note that all States currently use U.S. Census data for redistricting, but that the census data does not always reflect voter status. Additionally, the former directors and a group of professors caution that ACS does not meet the rigorous degree of statistical precision that important Constitutional decisions should require.


The Court will decide whether voter population is the appropriate apportionment base to satisfy the one-person, one-vote principle. Evenwel argues that the one-person, one-vote principle protects eligible voters from vote dilution, and that using voter population as the apportionment base is necessary to prevent dilution. Abbott stresses the impracticability of using such an apportionment base and argues that utilizing total population does not unconstitutionally dilute an individual’s voting power. The Court’s decision could affect the voting power of eligible voters, and the method and amount of data collection states must engage in to constitutionally apportion voting districts.

Edited by 


Additional Resources