Viki Harrison is the executive director of Common Cause New Mexico.

Equal protection of the laws. One person, one vote.

Every schoolkid learns these expressions of America’s highest ideals. They declare that wherever we live, whatever our color or gender, our religion or our station in life, we’re equal in the law’s eyes and have an equal share in our democracy.

This Tuesday in Washington D.C., the court entrusted with protecting those ideals will be asked to re-define them.

The case, Evenwel v. Abbott, centers on who should be counted when it comes to drawing state legislative districts. The plaintiffs want the Supreme Court to overturn decades-old precedents and change the meaning of “one person, one vote” so that every state legislative district will have roughly the same number of eligible voters rather than the same number of residents.

The Constitution requires that congressional districts be allocated among the states based on the “whole number of persons for each state;” that means everyone is counted—even those not able to vote. Why should state or city and county districts be different? And if the plaintiffs win their appeal, how crazy is it that congressional districts would be drawn using one set of criteria and state legislatures drawn with another?

The two plaintiffs in Evenwel are Texans, each of whom lives in a state Senate district with a total population roughly equal to that of other Texas districts but with a voting age population that is larger than that of other districts. That means it takes more votes to decide elections in their districts than in many others and that each vote cast in their districts has less weight than a vote cast elsewhere.

Lower courts have rejected the Texans’ claim that the difference in voting strength violates the “one person, one vote” principle. But if the Evenwel plaintiffs win, New Mexico’s legislature could be forced to re-draw the state’s political map so that rather than containing the same number of people, as they do now, each district would have the same number of voters.

Taxpayer dollars for things like schools and roads now flow to districts based on their total population, not just their eligible-to-vote counts; if districts are drawn based only on eligible voters, then we leave out lawful permanent residents and everyone under age 18. And what happens then? Support for vital public services used by everyone – like schools, fire and police protection, and roads – will be spread unevenly, with the largest share of money going to areas with a higher voting age population.

In a friend of the court brief filed in advance of this week’s hearing, Common Cause argues that the 14th amendment’s guarantee of ‘Equal Protection of the Laws” covers everyone, not just voters or those eligible to vote. “Each person in the United States is equally subject to the authority of federal and state government. Because those governments are republican in form,” the brief asserts, “representation is essential to legitimately subject persons to the laws they enact.”

The brief argues that to meet the high court’s “one person, one vote” requirement, a state must ensure only that any vote cast within a district have equal weight to others in that district. The Texas districts satisfy that demand, it asserts.

Voting rights advocates are paying especially close attention to Evenwel, as it comes just two years after a 5-4 majority of the high court, in Shelby County v. Holder, gutted a key section of the Voting Rights Act. That ruling made it easier for states to erect obstacles to voting for millions of students, the elderly and infirm and people of color. Luckily that hasn’t happened here in New Mexico!

Evenwel invites the justices to additional mischief with our democracy. If a majority accepts that offer, it will further undermine the high court’s standing as guarantor of our most important principles.

Common Cause is a nonpartisan grassroots organization dedicated to upholding the core values of American democracy. It works to create open, honest, and accountable government that serves the public interest; promote equal rights, opportunity, and representation for all; and to empower all people to make their voices heard as equals in the political process.