The federal appeals court in Boston ruled Thursday that Maine’s 72-hour waiting period on gun purchases will remain on hold pending a broader appeal from the state attorney general’s office.

State lawmakers passed the 72-hour bill last year along with several other gun safety reforms following the mass shooting in Lewiston in October 2023 that killed 18 people and wounded more than a dozen others. It required any gun seller who violated the waiting period to pay fines between $200 and $1,000, depending on the nature of the violation.

Gun rights advocates quickly sued the state in November after Gov. Janet Mills allowed it to become law without her signature. Chief U.S. District Judge Lance Walker then granted their request in February to temporarily pause the law, siding with their arguments that the waiting period likely violated their constitutional right to bear arms.

The Office of the Maine Attorney General immediately appealed that decision to the 1st U.S. Circuit Court of Appeals in Boston. Chief Deputy Attorney General Christopher Taub has argued the law saves lives and that it doesn’t infringe on Mainers’ constitutional ability to bear arms.

Taub asked Walker if the law could be temporarily restored, pending the appeal, which Walker also denied in March. The appeals court is still weighing that aspect of the case.

The 1st Circuit wrote in Thursday’s ruling that the question at the center of Maine’s case is so new, “in an emerging area of constitutional law involving a legal standard that is difficult to apply and subject to varying interpretations,” that they are not persuaded the law should be restored at this point in the legal battle.