It is fitting that the case comes out of Texas. As I wrote last week, the Hispanic population boom helped earn the state four additional Congressional seats after the release of the last census, in 2010. Given Hispanics’ partisan tendencies, at least a couple of those seats seemed bound to go to the Democrats, along with some House and Senate seats. But the Republicans who control the Texas State House, and with it the redistricting process, were able to devise a plan to keep that from happening, largely by using highly sophisticated gerrymandering techniques to dilute Hispanic voting blocs. That plan, devised in 2011, was halted in court and is still facing a legal challenge. But when it comes to state and local districts, success in the Evenwel case would likely render any such gerrymandering unnecessary. (Some legal scholars believe the same would eventually hold true for Congressional districts, too — for more on that question, check out this Election Law Blog post by Rick Hasen, a professor of law and political science at the University of California, Irvine.)

If the court rules that states and municipalities must base their political districts on populations of “eligible voters” — that is, citizens who are 18 and older — districts would become less Hispanic and more Anglo. Most of the news coverage of the case has provided the easiest-to-grasp reason for this: because most noncitizens are Hispanic immigrants. But the removal of children from the population figures would have a far greater impact, according to civil rights lawyers involved in the case — especially in places like Texas. A large number of noneligible voters in the state are Hispanic children, most of whom (per the State Demographer’s Office) happen to be citizens. By switching to an “eligible voter” standard, you effectively disappear the higher Hispanic birthrate, at least until those babies and toddlers turn 18.

“If you’re no longer drawing lines on population but you’re selectively using criteria like age, that hits our community very hard,” Nina Perales, vice president of litigation at the Mexican American Legal Defense and Educational Fund — which is helping to fight the case — told me during an interview last month in San Antonio. “Put aside the whole citizenship issue. The largest group of people who would be subtracted from the apportionment base would be children, and because we have disproportionately so many more children than the Anglo population has, that starts shifting seats all by itself, before you start to even consider citizenship.”

RUTENBERG: “An Element of Fairness”

During an interview at his home in Maine last summer, Ed Blum, the founder of the Project on Fair Representation, told me his interest in the case stems from his conviction that the current standards undermine the rights of voting citizens. “I want an element of fairness brought in,” Blum told me, “because I do think it’s unfair when each district has 100,000 persons but one district has 90,000 who are eligible to vote whereas a neighboring district only has 40,000 or 50,000 eligible to vote — 50,000 get one representative whereas 90,000 people get one representative.” In Blum’s view, then, not all eligible voters are equally represented. The original suit called upon the court to force Texas to take into account eligible voters’ “right to an equally weighted vote.” Blum told me he was not wedded to stripping citizen children from the population, but it’s hard to see how the court could, or would, parse that from a requirement to weight districts toward eligible voters.

And the lawyers for Blum’s group seem committed to a strict definition of “eligible voters,” even when faced with patently unjust hypotheticals. As our colleague Adam Liptak wrote, during this month’s oral arguments Justice Ruth Bader Ginsburg asked William Consovoy, a lawyer for the plaintiffs, whether women should have been excluded from political population counts before they had the right to vote. Consovoy, after some pressing, answered: “An equal weight for voters has to matter. A noncitizen or any other disenfranchised person would not have the ability to bring a one-person, one-vote claim.” He said disenfranchisement could be, and had been, remedied through other political and legal means. He didn’t say it outright, but he was partly referring to the Voting Rights Act of 1965, which drew the final curtain on the discriminatory voting laws of the Jim Crow era — the same law Blum’s group had successfully moved the court to gut in 2013.

BAZELON: And the Verdict Will Be ...

If Blum’s case succeeds in creating a requirement that states use voter rolls or eligible voters for political districts, it would be incredibly disruptive across the country. It’s a logistical mess. Not gonna happen.