WASHINGTON >> Pennsylvania’s congressional district map is a partisan gerrymander that “clearly, plainly and palpably” violates the state’s constitution, the state’s Supreme Court said today, joining a string of court decisions that have struck down political maps that unduly favor one political party.

The court banned the current map of 18 House districts from being used again, and ordered that a proposed new map be submitted to the court by Feb. 15. But the state’s Republican-dominated legislature, which approved the current district map in 2011, has already said it would seek to overturn such a decision in federal court. That would set up another legal battle over gerrymanders in a year already filled with them.

Whether such an appeal would succeed is debatable, because the Pennsylvania ruling is based entirely on the map’s adherence to the state constitution.

For the same reason, the state court’s decision has no direct bearing on a string of challenges to partisan gerrymanders already moving through the federal court system. Earlier this month, in fact, a divided panel of three federal judges left the same Pennsylvania congressional map intact.