MR. JUSTICE BRENNAN delivered the opinion of the Court.
In Wesberry v. Sanders, 376 U.S. 1 (1964), we held that "[w]hile it may not be possible [for the States] to draw congressional districts with mathematical precision," id., at 18, Art. I, § 2, of the Constitution requires that "as nearly as is practicable one man's vote in a congressional
The Missouri congressional redistricting statute challenged in these cases resulted from that State's second attempt at congressional redistricting since Wesberry was decided. In 1965, a three-judge District Court for the Western District of Missouri declared that the Missouri congressional districting Act then in effect was unconstitutional under Wesberry but withheld any judicial relief "until the Legislature of the State of Missouri has once more had an opportunity to deal with the problem. . . ." Preisler v. Secretary of State of Missouri, 238 F.Supp. 187, 191. Thereafter, the General Assembly of Missouri enacted a redistricting statute, but this statute too was declared unconstitutional. The District Court, however, retained jurisdiction to review any further plan that might be enacted. Preisler v. Secretary of State of Missouri, 257 F.Supp. 953 (1966), aff'd, sub nom. Kirkpatrick v. Preisler, 385 U.S. 450 (1967). In 1967, the General Assembly enacted the statute under attack here, Mo. Rev. Stat., c. 128 (Cum. Supp. 1967), and the Attorney General of Missouri moved in the District Court for a declaration sustaining the Act and an order dismissing the case.
Based on the best population data available to the legislature in 1967, the 1960 United States census figures, absolute population equality among Missouri's 10 congressional districts would mean a population of 431,981 in each district. The districts created by the 1967 Act, however, varied from this ideal within a range of 12,260 below it to 13,542 above it. The difference between the least and most populous districts was thus 25,802. In percentage terms, the most populous district was 3.13%
The District Court found that the General Assembly had not in fact relied on the census figures but instead had based its plan on less accurate data. In addition, the District Court found that the General Assembly had rejected a redistricting plan submitted to it which provided for districts with smaller population variances among them. Finally, the District Court found that the simple device of switching some counties from one district to another would have produced a plan with markedly reduced variances among districts. Based on these findings, the District Court, one judge dissenting, held that the 1967 Act did not meet the constitutional standard of equal representation for equal numbers of people "as nearly as practicable," and that the State had failed to make any acceptable justification for the variances. 279 F.Supp. 952 (1967). We noted
Missouri's primary argument is that the population variances among the districts created by the 1967 Act are so small that they should be considered de minimis and for that reason to satisfy the "as nearly as practicable" limitation and not to require independent justification. Alternatively, Missouri argues that justification for the variances was established in the evidence: it is contended that the General Assembly provided for variances out of legitimate regard for such factors as the representation of distinct interest groups, the integrity of county lines, the compactness of districts, the population trends within the State, the high proportion of military personnel, college students, and other nonvoters in some districts, and the political realities of "legislative interplay."
We reject Missouri's argument that there is a fixed numerical or percentage population variance small enough to be considered de minimis and to satisfy without question the "as nearly as practicable" standard. The whole thrust of the "as nearly as practicable" approach is inconsistent with adoption of fixed numerical standards which excuse population variances without regard to the circumstances of each particular case. The extent to which equality may practicably be achieved may differ from State to State and from district to district. Since "equal representation for equal numbers of people [is] the fundamental goal for the House of Representatives," Wesberry v. Sanders, supra, at 18, the "as nearly as practicable" standard requires that the State make a good-faith effort to achieve precise mathematical
There are other reasons for rejecting the de minimis approach. We can see no nonarbitrary way to pick a cutoff point at which population variances suddenly become de minimis. Moreover, to consider a certain range of variances de minimis would encourage legislators to strive for that range rather than for equality as nearly as practicable. The District Court found, for example, that at least one leading Missouri legislator deemed it proper to attempt to achieve a 2% level of variance rather than to seek population equality.
Equal representation for equal numbers of people is a principle designed to prevent debasement of voting power and diminution of access to elected representatives. Toleration of even small deviations detracts from these purposes. Therefore, the command of Art. I, § 2, that States create congressional districts which provide equal representation for equal numbers of people permits only the limited population variances which are unavoidable despite a good-faith effort to achieve absolute equality, or for which justification is shown.
Clearly, the population variances among the Missouri congressional districts were not unavoidable. Indeed, it is not seriously contended that the Missouri Legislature came as close to equality as it might have come. The District Court found that, to the contrary, in the two reapportionment efforts of the Missouri Legislature since Wesberry "the leadership of both political parties in the Senate and the House were given nothing better to work with than a makeshift bill produced by what has been candidly recognized to be no more than . . . an expedient political compromise." 279 F. Supp., at 966. Legislative
We therefore turn to the question whether the record establishes any legally acceptable justification for the population variances. It was the burden of the State "to present . . . acceptable reasons for the variations among the populations of the various . . . districts . . . ." Swann v. Adams, supra, at 443-444.
We agree with the District Court that Missouri has not satisfactorily justified the population variances among the districts.
Missouri contends that variances were necessary to avoid fragmenting areas with distinct economic and social interests and thereby diluting the effective representation of those interests in Congress. But to accept population variances, large or small, in order to create districts with specific interest orientations is antithetical to the basic premise of the constitutional command to provide equal representation for equal numbers of people. "[N]either history alone, nor economic or other sorts of group interests, are permissible factors in attempting to justify disparities from population-based representation. Citizens, not history or economic interests, cast votes." Reynolds v. Sims, supra, at 579-580. See also Davis v. Mann, 377 U.S. 678, 692 (1964).
We also reject Missouri's argument that "[t]he reasonableness of the population differences in the congressional districts under review must . . . be viewed in the context of legislative interplay. The legislative leaders all testified that the act in question was in their opinion a reasonable legislative compromise. . . . It must be remembered . . . that practical political problems are inherent in the enactment of congressional reapportionment legislation."
Similarly, we do not find legally acceptable the argument that variances are justified if they necessarily result from a State's attempt to avoid fragmenting political
Missouri further contends that certain population variances resulted from the legislature's taking account of the fact that the percentage of eligible voters among the total population differed significantly from district to district—some districts contained disproportionately large numbers of military personnel stationed at bases maintained by the Armed Forces and students in attendance at universities or colleges. There may be a question whether distribution of congressional seats except according to total population can ever be permissible under Art. I, § 2. But assuming without deciding that apportionment may be based on eligible voter population rather than total population, the Missouri plan is still unacceptable. Missouri made no attempt to ascertain the
Missouri also argues that population disparities between some of its congressional districts result from the legislature's attempt to take into account projected population shifts. We recognize that a congressional districting plan will usually be in effect for at least 10 years and five congressional elections. Situations may arise where substantial population shifts over such a period can be anticipated. Where these shifts can be predicted with a high degree of accuracy, States that are redistricting may properly consider them. By this we mean to open no avenue for subterfuge. Findings as to population trends must be thoroughly documented and applied throughout the State in a systematic, not an ad hoc, manner. Missouri's attempted justification of the substantial underpopulation in the Fourth and Sixth Districts falls far short of this standard. The District Court found "no evidence . . . that the . . . General Assembly adopted any policy of population projection in devising Districts 4 and 6, or any other district, in enacting the 1967 Act." 279 F. Supp., at 983.
Finally, Missouri claims that some of the deviations from equality were a consequence of the legislature's attempt to ensure that each congressional district would be geographically compact. However, in Reynolds v. Sims,
[For dissenting opinion of MR. JUSTICE HARLAN, see post, p. 549.]
[For dissenting opinion of MR. JUSTICE WHITE, see post, p. 553.]
MR. JUSTICE FORTAS, concurring.
I concur in the judgment of the Court in these cases, but I cannot subscribe to the standard of near-perfection which the Court announces as obligatory upon state legislatures facing the difficult problem of reapportionment for congressional elections.
In Wesberry v. Sanders, 376 U.S. 1 (1964), this Court recognized that "it may not be possible to draw congressional districts with mathematical precision," and it held that the Constitution requires that they be drawn so that, "as nearly as is practicable," each representative
The Court now not only interprets "as nearly as practicable" to mean that the State is required to "make a good-faith effort to achieve precise mathematical equality," but it also requires that any remaining population disparities "no matter how small," be justified. It then proceeds to reject, seriatim, every type of justification that has been—possibly, every one that could be—advanced.
I agree that the state legislatures should be required to make "a good-faith effort to achieve" a result that allocates the population or the residents
In considering whether the State has "approximated" an equal division and allocation of the population, I sympathize with the majority's view that a de minimis rule of allowable disparities tends to demean in theory and in practice the constitutional objective because it suggests that it is not necessary even to aim at equality. On the other hand, to reject de minimis as a statement of the limits on the rule of equality should not lead us to toss aside the wise recognition of the inscrutability of fact and the imperfection of man which is implicit in the Wesberry standard: "as nearly as practicable." This phrase does not refer merely to arithmetical possibilities. Arithmetically, it is possible to achieve division of a State into districts of precisely equal size, as measured by the decennial census or any other population base. To carry out this theoretical possibility, however, a legislature might have to ignore the boundaries of common sense, running the congressional district line down the middle of the corridor of an apartment house or even dividing the residents of a single-family house between two districts. The majority opinion does not suggest so extreme a practical application of its teaching, and I mention it only because the example may dramatize the fallacy of inflexible insistence upon mathematical exactness, with no tolerance for reality.
Whatever might be the merits of insistence on absolute equality if it could be attained, the majority's pursuit of precision is a search for a will-o'-the-wisp. The fact is that any solution to the apportionment and districting
Nothing that I have said should be taken as indicating that I do not believe that the Wesberry standard requires a high degree of correspondence between the demonstrated population or residence figures and the district divisions. Nor would I fix, at least at this relatively early stage of the reapportionment effort, a percentage figure for permissible variation.
In the present cases, however, I agree that the judgment of the District Court should be affirmed. The history of this reapportionment and of the legislature's failure to comply with the plain and patient directions of the three-judge District Court and the failure of the legislature to use either accurate 1960 census figures or other systematically obtained figures for all the districts— these factors strongly support the District Court's refusal
% Variation District No. Population. From Ideal. One 439,746 + 1.80 Two 436,448 + 1.03 Three 436,099 + 0.95 Four 419,721 - 2.84 Five 431,178 - 0.19 Six 422,238 - 2.26 Seven 436,769 + 1.11 Eight 445,523 + 3.13 Nine 428,223 - 0.87 Ten 423,868 - 1.88
Far more significant than variations between successive enumerations are errors—virtually all undercountings—which are produced by the inherent limitations of the enumerating system. A Census Bureau estimate indicates that the 1960 census counted only 96.9% of the whole population, 3.1% of the people not being found and counted by the enumerators. Undercounting was not evenly distributed over the whole population. Instead, members of certain groups, notably young adult Negroes, were far more likely to be missed by the enumerators. For nonwhites in all age groups the census was estimated to understate the actual population by 9.5%. For young adult Negro males, undercounting reached nearly 20% for some five-year age groups. See generally, Siegel, Completeness of Coverage of the Nonwhite Population in the 1960 Census and Current Estimates, and Some Implications, Report, Conference on Social Statistics and the City (Washington, D. C., June 22-23, 1967) 13 (Heer ed., 1968). Because the heavily undercounted groups are not evenly distributed over the country, the differential rates of undercounting produce divergences between the actual relative populations of particular areas and those indicated by the census.
"For the present, we deem it expedient not to attempt to spell out any precise constitutional tests. What is marginally permissible in one State may be unsatisfactory in another, depending on the particular circumstances of the case. Developing a body of doctrine on a case-by-case basis appears to us to provide the most satisfactory means of arriving at detailed constitutional requirements in the area of state legislative apportionment."