One Person, One Vote, One Still Unsettled Democratic Principle

It's the bedrock of modern American democracy: one person, one vote. But that seemingly simple principle can raise major ambiguities when it comes to legislative districting. Who, after all, counts as 'one person,' when drawing election districts? All residents, all citizens, all voters?

Today, the Supreme Court unanimously rejected a challenge that sought to make "one person" mean "one voter." States are free to use total population numbers, the Court ruled. But it didn't foreclose the possibility that, when it comes to "one person, one vote," there could be more than one way of counting.

One Person? Or One Voter?

The case, Evenwel v. Abbott, arose after Texas began reapportioning its state senate districts following the 2010 census. Under the principle of "one person, one vote," those districts have to be roughly proportional; each state senator should represent about the same amount of people.

When drawing those lines, Texas does the same as all states: it uses total population numbers from the census. But those numbers include plenty of non-voters: unregistered Texans, non-citizens, children, and felons.

So, while the Texas system allowed for a more-or-less equal distribution on the basis of population, some districts had many more eligible and registered voters than others, deviating by up to 40 percent. Conservative activists sued, arguing that the Equal Protection Clause required Texas to equalize both total population and voter population.

A Strong Defense of Total Population

The Court resoundingly rejected that argument today. It is "plainly permissible" for States and localities to base legislative districts on total population, Justice Ginsburg wrote for the Court. However, the Court's opinion stopped short of requiring states to use total population, or even affirmatively defining the limits what "one person, one vote" could mean.

The Court gave several reasons for allowing the status quo to remain. First, there was long historical precedent for the use of total population, including the Founding Fathers' apportionment of representatives according to a state's total population -- minus non-voting slaves, who were counted as three fifths a person. Later, Congress expressly rejected a proposal to use voter population as the basis for apportioning House seats.

Similarly, Supreme Court precedent has consistently looked at total-population figures to determine whether legislative districts were equal. There's good reason for that, as well, Justice Ginsburg explains, as representatives represent all people, not just voters.

But It Might Not Be Limited to That

But the strong defense of "one person" as any person, voter or not, stopped short of saying that total population was the only way to meet the requirements of "one person, one vote." The limits of "one person, one vote" remain unsettled. "We need not and do not resolve," the Court explained, whether "states may draw districts to equalize voter-eligible population rather than total population."

Indeed, the possibility of alternatives to total population was highlighted in both Justice Alito's and Justice Thomas's concurrences. The constitutionality of alternative systems, Justice Alito emphasized, remains an open question. Justice Thomas went the farthest, claiming that a state may permissibly "use total population, eligible voters, or any other nondiscriminatory voter base." Yet he was alone in making such a direct endorsement.

So, the current system remains largely unchanged. The Court has fully endorsed the use of total population, but in doing so, it has also emphasized the possibility that "one person, one vote" may not be limited to current practice. Whether any states will pursue alternatives -- and whether those alternatives will pass constitutional muster -- remains to be seen.

Related Resources:

• Supreme Court Rejects Conservative Challenge to 'One Person, One Vote' (The Washington Post)
• Justices Take Cautious Approach to 'One Person, One Vote' (FindLaw's U.S. Supreme Court Blog)
• Studies Show: Ginsburg Was Correct in Voting Rights Act Dissent (FindLaw's U.S. Supreme Court Blog)
• SCOTUS to Review Texas Congressional Redistricting Map (FindLaw's U.S. Supreme Court Blog)