The U.S. Supreme Court finally may choose to decide how much partisan advantage is too much when a political party draws congressional districts.

The justices agreed Friday to hear arguments in lawsuits involving the congressional maps in North Carolina and Maryland. Districts in both states had been declared unconstitutional by trial court panels in different federal judicial circuits.

Courts in recent decades have regularly struck down districts which were drawn in a manner that denied equal protection to racial minorities. In contrast to those racial gerrymandering cases, the nation’s highest court has reached no conclusion on partisan gerrymandering. While some justices have been willing to accept the notion that partisan gerrymandering could be unconstitutional, others have argued that courts have no business meddling in a political issue.

Former Justice Anthony Kennedy had acted as a swing vote. He agreed with the court’s “liberal” bloc that partisan gerrymandering could be unconstitutional. But Kennedy never provided a deciding fifth vote for a judicial standard that would strike down an electoral map as overly partisan.

The N.C. and Maryland cases will mark the first time the U.S. Supreme Court has addressed the partisan gerrymandering issue since Justice Brett Kavanaugh replaced Kennedy.

In late August, a three-judge federal court panel issued a 321-page ruling in Common Cause v. Rucho, saying the most recent set of maps drawn by North Carolina’s Republican-dominated General Assembly gave GOP candidates an unfair advantage over Democrats. The court said the maps suppressed the political speech of voters who belong to the minority party in a district, violating the First and 14th Amendments and portions of Article I of the U.S. Constitution.

“By definition, partisan gerrymandering amounts to an effort to dictate electoral outcomes by favoring candidates of one party and disfavoring candidates of another,” said 4th U.S. Circuit Court of Appeals Judge James Wynn for the court.

The Supreme Court allowed the current districts — which were redrawn under court order for the 2016 election — to remain in effect for the 2018 cycle.

The Maryland case involves congressional maps drawn by Democrats. In Lamone v. Benisek, a three-judge panel in June said the map drawers in Maryland designed the 6th Congressional District in such a manner that it was nearly impossible to elect a Republican there.

In a press release, Common Cause North Carolina Executive Director Bob Philips said, “We are confident that, just as the federal District Court did, the Supreme Court will rule that partisan gerrymandering violates the constitutional rights of voters. This case is key to finally ending gerrymandering in North Carolina and across the nation.”

If the justices order new congressional maps, they will be in place only for the 2020 election. The 2020 census will require a reapportionment of congressional districts. North Carolina’s population growth over the past decades puts the Tar Heel State in line to gain a 14th district, so new maps reflecting those population shifts will be drawn for the 2022 election.