North Carolina Republicans lied to a federal court in 2017 when they claimed that they didnt use racial data about voters as they drew new electoral maps, according to a blistering filing in a partisan gerrymandering lawsuit this week.

Common Cause of North Carolina, the lead plaintiff in the case, says the states legislative maps are so gerrymandered to benefit Republicans that they violate the states constitution. The daughter of Thomas Hofeller, a GOP master of gerrymandering who assisted lawmakers in drawing the maps, gave the files to the voting rights group. Stephanie Hofeller found the files after her father died last August, and lawyers representing Common Cause subpoenaed them.

The files contained evidence that North Carolina Republicans misled the court both about how racial data was considered in creating the maps and their ability to create new ones in time for a special election, according to the filing. The court opted not to order special elections in 2017, leaving lawmakers elected under racially gerrymandered maps in power for a little bit longer.

North Carolina has been ground zero in the battle over redistricting over the last decade. The Supreme Court is set to rule this month on whether the states congressional map is unconstitutionally gerrymandered for partisan gain. The new filings suggest the extent to which lawmakers were willing to go to preserve their power.

After getting caught racially gerrymandering in 2017, the North Carolina lawmakers told the court late they didnt use racial data when they drew the new maps. Lawmakers told the court in September 2017 that data regarding race of voters was not even loaded into the computer used by the map drawer to construct the districts.

But Hofellers files show he did consider racial data when drawing the maps, according to the filing. All of Hofellers draft maps include racial data, the lawyers said. State Rep. David Lewis, a Republican who played a lead role in drawing the new maps, strongly denied he and other lawmakers misled the court. He suggested Hofeller was drawing maps with racial data in his spare time .