PORTLAND, Maine (AP) A federal judge on Thursday put a hold on a new three-day waiting period for gun purchases in Maine after reviewing a lawsuit filed against the rule by gun rights groups.

Maine’s new gun rule took effect in August and was one of several gun control measures the state’s Democratic-controlled Legislature passed after an Army reservist killed 18 people in Lewiston in October 2023 in the deadliest shooting in state history. Gun rights advocates challenged the waiting period law and asked for it to be paused pending the outcome of their case.

The gun advocates contend the law violates their 2nd Amendment rights. Federal judge Lance Walker wrote that the act “employs no standard at all to justify disarming individuals,” and that the plaintiffs are likely to succeed.

The lawsuit was filed on behalf of a group of individuals who contend it is illegal to require a person who passed a background check to wait 72 hours before completing a gun purchase. Maine’s attorney general has said he intends to defend the law and that waiting periods have been upheld in other parts of the country.

Similar laws exist in about a dozen other states. Gun control advocates in Maine trumpeted the law as way to provide a cooling-off period for people intending to use a gun to do harm to others or themselves.