A lawsuit has been filed by advocacy groups arguing that North Carolina’s 2016 congressional redistricting plan violates the First and Fourteenth Amendment of US Constitution.

The Southern Coalition for Social Justice and the Campaign Legal Center announced the lawsuit on Thursday on behalf of the League of Women Voters of North Carolina.

The lawsuit, League of Women Voters of North Carolina v. Rucho, was filed in the US District Court for North Carolina’s Middle District, according to a release.

The lawsuit comes after the Fourth Circuit Court of Appeals has ruled that North Carolina’s congressional districts were unconstitutional. The maps that were ruled on were drawn by the Republican-led General Assembly following the 2011 census and have been winding through the court system since.

A special primary was held in June for congressional races in the Tar Heel state after a federal court ordered the legislature to redraw the districts because of racial gerrymandering used when drawing the maps. Legislative leaders made clear when announcing the new congressional districts that the new map was drawn with intent to keep the GOP’s 10-3 majority from North Carolina in the US House of Representatives.

While the lawsuit focuses on congressional districts, the federal court also ruled the legislative districts were unconstitutional but allowed the districts to be used this November. The court said it was too close to the election for new districts to be drawn, approved and a new primary to be held.

Southern Coalition for Social Justice executive director Anita Earls issued the following statement regarding Thursday’s lawsuit.

“The Constitution guarantees everyone’s right to participate equally in an electoral system that does not discriminate against them because of their beliefs. It’s clear that the intent and effect of creating North Carolina’s 2016 congressional maps were to manipulate the democratic process. The result disparages voters and ensures that one party can maintain political power even when a majority of the state’s voters do not support them.”

Campaign Legal Center executive director Gerry Hebert also issued a statement.

“When it comes to congressional districts, North Carolina’s are an extreme and egregious partisan gerrymander. Packing and cracking voters in districts based on their political ideology and voting history classifies voters in an invidious manner unrelated to any legitimate legislative objective. Radical partisan gerrymandering like that in this case turns democracy on its head. For the sake of North Carolina voters and voters across our nation, this practice must come to an end. The implementation of our efficiency gap standard would go a long way in ensuring that every voter is entitled to equal protection under the law and having their voice heard.”