When the Supreme Court first established the “one person, one vote” standard, it was responding to a basic electoral problem: District lines for state legislatures had not kept pace with urbanization. Depopulated rural areas thus maintained disproportionate voting power.

It wasn’t a novel issue. Britain went through its own reform to fix “rotten boroughs” in which some members of Parliament represented literally nobody. But it took the 1964 case of Reynolds v. Sims to require states to draw districts with roughly equal populations.

“One person, one vote” is now a well-accepted part of our constitutional democracy. Everybody’s vote is equal, and nobody gets more votes based on wealth, education, occupation, sex, race or geography. But in the half-century since Reynolds and related rulings, further demographic shifts have complicated the implementation of this concept.

Just as the Industrial Revolution heralded population moves toward cities, immigration patterns have created disparities in the number of voters per district. Just as it was intolerable for a rural district with 500 voters to have the same representation as an urban district with 5,000 voters, it’s now constitutionally suspect to have that disparity between a heavily non-citizen district and one where nearly all adults are eligible to vote.

Reynolds came at a time when the foreign-born population was at a record low, whereas now we’re at levels not seen since the Ellis Island days of the early 20th century. The Supreme Court must thus intervene again, to maintain voter equality by specifying that “one person, one vote” demands an equalization of voters rather than population.

Otherwise, you end up with the scenario we see in Texas. Depending on where you live in the Lone Star State, you might be one of 383,000 people who choose a state senator, or one of 611,000. Indeed, the legislature could’ve drawn 31 districts of equal population where 30 have one voter each and the 31st all the other voters.

That can’t be right. If “one person, one vote” means anything, it’s that we can’t weigh some people’s votes more than others’.