A New York state judge threw out the state’s congressional map Thursday, ruling that Democrats who control the state legislature cannot ignore a 2014 constitutional amendment creating a commission to create nonbiased maps. 

That commission, known as the Independent Redistricting Commission, did not submit a second map proposal after its first failed to gain enough support. The Democratic-controlled legislature then passed its own maps.

“The legislature is not free to ignore the IRC maps and develop their own,” acting Supreme Court Justice Patrick McAllister wrote in an 18-page ruling.

The ruling, which is expected to be stayed and appealed, comes as candidates have been collecting signatures to get on the ballot. McAllister wrote that the court would give the legislature until April 11 “to enact new bipartisan supported proposed maps that meet the constitutional requirements.” 

Mike Murphy, a spokesman for the state Senate Democratic majority, said the ruling was “one step in the process.”

“We always knew this case would be decided by the appellate courts. We are appealing this decision and expect this decision will be stayed as the appeal process proceeds,” he told Zack Fink, a New York politics podcaster. 

The map crafted by the legislature gave Democrats an opportunity to pick up as many as three additional House seats in a year. The state lost one seat in reapportionment.