WHEN THE Supreme Court decided in June that it was ill-suited to policing partisan gerrymandering, Chief Justice John Roberts wove in a faint silver lining for fans of democracy. Federal courts may not be cut out to decide when state legislatures go too far in drawing electoral lines to entrench one party in power, but state courts are another matter. “Provisions in state statutes and state constitutions can provide standards and guidance for state courts to apply”, the chief wrote in Rucho v Common Cause, pointing to the example of a 2015 Florida court decision nullifying its congressional map. Challenges to partisan gerrymandering need not, Chief Justice Roberts wrote, “echo into a void”.

On October 28th, a state court in North Carolina inserted itself into the void. The same skewed congressional map that the justices declined to straighten out in accordance with the federal constitution four months ago is now effectively erased as a violation of North Carolina’s state constitution. Republican legislators who crafted the map to guarantee them 10 of North Carolina’s 13 seats in Congress—despite the state’s roughly 50-50 split between Republicans and Democrats—will have no appeal beyond North Carolina’s highest court, where six of the seven justices are Democrats. The federal Supreme Court has no jurisdiction to review a state supreme court’s ruling on the meaning of its own state constitution.

The three-judge panel’s crisp 18-page opinion explains the origins of the lopsided map and why it chafes against three separate provisions of the North Carolina constitution. When the Republican majority in the state legislature drew the map in 2016 after the Supreme Court found its previous map was illegally gerrymandered along racial lines, legislators announced their updated gerrymander was partisan, not race-based. The only reason the new map favours the Republican Party by a 10-3 margin is, one cartographer said, “because I do not believe it’s possible to draw a map with 11 Republicans and two Democrats.”

This blatant and “extreme” partisan gerrymander, the North Carolina court found, violates two rights protected by the state constitution with analogues to the federal constitution: equal protection and freedom of speech and assembly. Equal protection, as North Carolina has understood the concept, includes “the fundamental right of each North Carolinian to substantially equal voting power”—an interpretation that “provides greater protection for voting rights than the federal equal-protection clause”. The free speech guarantee prohibits the “packing” and “cracking” of “disfavoured speakers...into legislative districts with the aim of diluting their votes”. And, unique to the North Carolina constitution, the standard that “all elections shall be free” requires a government “in which the will of the people—the majority—legally expressed, must govern”. A partisan gerrymander like the Republican-engineered map “evince[s] a fundamental distrust of voters by serving the self-interest of political parties over the public good” and cannot stand.

What happens next? Technically, the October 28th ruling—issued just five days after the hearing—represents not a final decision but a “preliminary injunction” against the Republican-drawn congressional map. Elisabeth Theodore, a lawyer at Arnold & Porter who helped challenge the map, says her team “will be moving for summary judgment shortly and seeking a permanent injunction against use of the map” in the 2020 election. “The court would not (and could not) have issued the preliminary injunction if it had not already concluded that we are likely to win on the merits and that the 10-3 map is unconstitutional”, she says.

When the ball is back in the Republican-held state legislature’s court, Republicans have no realistic chance of keeping their lock on ten seats in the House of Representatives. They could try to use the purportedly neutral principle of incumbency protection to draw a map that keeps 8 or 9 of those seats painted red—a strategy underlying their redrafted state legislative map which was approved by the same court this week—but they must tread carefully. The three judges adjudicating the matter will have no patience for a map that continues to favour Republicans unduly. They will probably appoint a non-partisan “special master” to evaluate the new districts, as they did in the case involving the state legislative maps. If the court balks at the revision, the special master could be tasked with redrafting it himself.

Time is short: the court wants to resolve the matter by the candidate filing deadline for congressional elections on December 20th. In its ruling this week, the court urged the state legislature to proceed “expeditiously” in turning around a fairer map. If the Republicans stonewall or tarry, they have little to gain. The judges noted that they are prepared to push back the March 3rd primary date “should doing so become necessary to provide effective relief” from the Republican-rigged district lines. “The loss to plaintiffs’ fundamental rights guaranteed by the North Carolina constitution", the court wrote, "will undoubtedly be irreparable if congressional elections are allowed to proceed under the 2016 congressional districts".