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This article is from the archive of our partner National Journal

The Supreme Court on Tuesday will debate whether to rewrite the rules for legislative redistricting—in a way that would further strengthen Republicans’ dominance in state politics.

State legislative districts are apportioned under the constitutional principle of “one person, one vote.” And, for decades, states have taken that to mean that each district should contain roughly the same number of people. But the challengers in the case before the high court Tuesday say that’s not the right interpretation. They say districts should be apportioned with equal numbers of eligible voters, rather than total residents.

If the challengers succeed, the case could usher in a redistricting revolution—and big gains for the GOP. Densely populated urban areas tend to lean Democratic, and also to contain more people who aren’t eligible or registered to vote. If state legislative districts were redrawn to equalize the number of eligible voters, rather than the number of total residents, inner cities' political power would likely be diluted into more conservative suburbs.

A host of liberal organizations, including the ACLU, the NAACP, and the Democratic National Committee, have filed amicus briefs urging the Court to reject the new standard and leave the state redistricting process alone.

“All residents—be they children, noncitizen immigrants, or eligible voters—are members of the wider political community whose interests should be taken into account by their elected representatives,” the DNC wrote. “Adopting Appellants’ position would be to adopt the view that all persons except eligible voters are nonentities as far as political representation is concerned.”

Most legal experts don’t expect the Court to go as far as a ruling requiring states to apportion their legislative districts based on the number of eligible voters—a change that former Census Bureau directors say would be hard, if not impossible, to make.

But some see a potential middle ground in the case: The Court could allow states to make their own decisions about how to draw district lines, rather than mandating either approach. That’s still too far for the DNC and the Obama administration, which argue that the standard must remain based on total population.

This article is from the archive of our partner National Journal.

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