In a pair of cases decided in 1964, the Supreme Court of the United States famously established the “one person, one vote” test. This meant that all congressional districts would be required to have the same number of people, while state legislative districts must have roughly the same number. The consequences of those decisions were both immediate and far-reaching. A wave of mid-decade redistricting swept the country, as virtually every congressional and legislative district had to be, at a minimum, tweaked to account for population discrepancies. Rural districts in particular lost representation, while the depopulation of urban centers helped usher in the rise of the suburbs in Congress.
Last week, the Supreme Court shocked watchers by agreeing to hear a case that could have consequences of a similar magnitude. In 1966, in a follow-up to the Reynolds v. Sims decision, the court had held that states did not necessarily need to use persons as the basis for their representation schemes. Since then the court has at times been asked to adopt various different metrics. It generally resisted these entreaties, although Justice Clarence Thomas has, at times, urged the court to take up these cases.
So most were caught off guard when the court decided to take up Evenwel v. Abbott. The plaintiffs in that case asked the court to clarify that onlycitizens should be counted for purposes of drawing legislative districts. The “why” of this is a bit complex, but it grows out of a (superficial, in my mind) tension between the 14th Amendment, which apportions voting districts on the basis of population, and the Voting Rights Act, which requires that states ensure there are a sufficient number of citizens of voting age in a given group to enable that group to elect a candidate of its choice.
If the court were to find for the plaintiffs – and it seems unlikely that the court would have gratuitously taken up this case, absent a circuit split, if there weren’t some substantial support for the plaintiffs’ position – it would mean that, once again, virtually every legislative and congressional district in the country would have to be redrawn (although this would not, as some have suggested, affectapportionment – i.e. the number of seats allocated to each state). This would occur at a time when Republicans control a record-high number of state legislatures and a majority of state governments. Republicans would be able to update their maps to account for changes in political orientations in their states since the previous round of redistricting.
But this would have implications for Democratic-controlled states as well. Consider that in 2012, counties with high citizen populations were more likely to vote for Mitt Romney (the t-stat is 9.047). Of the 35 states with four or more congressional districts, there was a statistically significant, positive correlation between the share of county residents who were citizens and the share of voters who cast ballots for Mitt Romney in 18 of the states, most of which are among our largest: California, Colorado, Florida, Illinois, Indiana, Kentucky, Maryland, Michigan, Minnesota, Missouri, Nevada, New York, Ohio, Oregon, Pennsylvania, Texas, Virginia and Wisconsin.
