In a great victory for American democracy, the Supreme Court ruled 8-0 today in Evenwel v. Abbott that when states fulfill their Equal Protection requirement to equalize populations within state legislative districts, they can use total population to do so.  The Court rejected the invitation to rule that states must use eligible voters as the measure, rather than total population.

Justice Ginsburg wrote for a six-person majority that included Chief Justice Roberts, as well as Justices Kennedy, Breyer, Sotomayor, and Kagan.  (Justices Alito and Thomas each concurred with the result but rejected the majority’s reasoning.)  Justice Ginsburg discussed the framers’ decision to write the Fourteenth Amendment to require representational equality in congressional House districts, which undermines the idea that the same amendment would prohibit states from taking the same approach to in-state legislative districts.  She also noted that the Court has never used eligible-voter data or registered-voter data in its analyses of permissible population variances among state districts.  The majority said that for decades in some cases and centuries in others, all states and countless local jurisdictions have used total population (with occasional small exceptions for non-permanent residents such as military personnel from out of state or inmates originally from out of state).

So why does this matter?  As Justice Ginsburg wrote:

As the Framers of the Constitution and the Fourteenth Amendment comprehended, representatives serve all residents, not just those eligible or registered to vote. Nonvoters have an important stake in many policy debates—children, their parents, even their grandparents, for example, have a stake in a strong public-education system—and in receiving constituent services, such as help navigating public-benefits bureaucracies. By ensuring that each representative is subject to requests and suggestions from the same number of constituents, total-population apportionment promotes equitable and effective representation.

It’s simple:  Everyone deserves representation.  And that is hard to square with the idea that only eligible voters should be counted.

As we wrote in our preview of the current Supreme Court term:

A ruling in favor of Evenwel would not just be a dramatic shift for the Court: It would be a dramatic shift in American politics, as well, with diverse urban areas losing political power to suburban and rural areas.  It is for this reason that Richard Hasen has called this case “an attempted [partisan] power grab in Texas and other jurisdictions with large Latino populations.”

There are other problems, as well.  For instance, if you base the population count on registered voters or on actual voters, then both systemic and intentional obstacles to voter registration and voting are made even worse, by further weakening the political influence of the targeted communities.  A community that has a lower registration rate or turnout for any reason should not be penalized by losing their right to representation in the legislature.

Today’s majority didn’t just give a powerful defense of using total population.  They also rejected an invitation to address the merits of using eligible voters.  An opinion upholding that approach as constitutional even if not mandatory could have served as a political weapon for conservatives seeking to use that system in the next round of state and local redistricting after the 2020 Census.  But Justice Ginsburg and the rest of the majority refused to take the bait, saying that simply was not an issue before the Court and need not be addressed.

But given her powerful defense of the current system of counting total population, conservatives will be hard pressed to argue for limiting the population count to those who are eligible to vote.  In today’s decision, only Justice Thomas’s concurrence concluded that such a system would be constitutional.