SANTA FE — Legislators are expecting the legal clash over New Mexico’s new congressional districts to move at a breakneck pace now that the Supreme Court has ruled partisan gerrymandering can violate the state Constitution.

Members of a key legislative committee heard a presentation Monday from their attorneys in the case — who said the state Supreme Court has set an aggressive schedule.

The lower-court judge handling a lawsuit filed by the Republican Party of New Mexico and others has been directed to resolve the complaint by Oct. 1, after which an appeal could propel the case back to the Supreme Court.

It means a fast-paced schedule ahead of the 2024 election cycle, when New Mexico’s three congressional districts are on the ballot.

“There will be lots of sleepless nights for a lot of attorneys across New Mexico,” Lucas Williams, a Roswell-based lawyer who is defending the Legislature, told lawmakers Monday.

The New Mexico justices, in a unanimous order July 5, cited a three-part test articulated by U.S. Supreme Court Justice Elena Kagan to determine whether partisan gerrymandering violates the equal protection clause of the New Mexico Constitution.

To succeed in their claim, opponents of the congressional map will have to show the predominant purpose of the redrawn districts was to entrench Democrats in power. They also must show the lines had the desired effect, by diluting Republican votes.

If they succeed on those two points, Democrats can still save the map by demonstrating they had a legitimate, nonpartisan justification for the districts.

In their ruling, Williams said, the justices also recognized that redistricting is an inherently political process and that some degree of partisan gerrymandering is permissible.

The decision creates “a somewhat blank slate. It will be litigated vigorously,” Williams said.

The map at stake substantially reshaped New Mexico’s congressional landscape before the 2022 election. For decades, the state had a northern district where Democrats succeeded, a southern district usually held by Republicans and a middle district in Albuquerque — often competitive, but more recently dominated by Democrats.

The new map divides Albuquerque in two and gives all three districts part of southeastern New Mexico, a traditional Republican stronghold.

The net result is three districts with a Democratic lean. And the delegation’s lone Republican, Yvette Herrell, lost her reelection bid last year.

In Monday’s meeting, state Rep. John Block, R-Alamogordo, said Democrats should have just accepted one of the maps recommended by the state’s nonpartisan citizen redistricting committee, which meet in 2021 after the census.

Instead, Democratic lawmakers amended one of the recommendations, he said, to dilute Republican votes. Under the map, Lovington in conservative southeastern New Mexico now shares a district with Democratic-leaning Española north of Santa Fe, he said.

“There is no way anyone can make a case this wasn’t partisan,” Block said. “It was absolutely partisan.”

Sen. Joseph Cervantes, a Las Cruces Democrat who co-sponsored the redistricting plan, said his motive was actually the opposite — to create competitive districts that neither party could take for granted.

Each district, he said, has a mix of community and political interests, intended as a contrast to the safe seats enjoyed by many in Congress across the county.

“Our democracy is terribly ill,” Cervantes said, “and we can set an example of how you fix that.”