The U.S. Supreme Court will not take up a challenge from gun rights groups to Maine’s 72-hour waiting period for firearm purchases.

The gun rights groups were seeking to overturn an appeals court decision that the Maine law is likely constitutional.

Maine lawmakers passed the waiting period in response to the Lewiston Mass Shooting that killed 18 people in 2023.  It took effect without the signature of Governor Janet Mills.

The waiting period remains in place, although the underlying lawsuit from the gun rights groups against the law will continue in a lower federal court in Maine.

The groups have argued the law violates their Second Amendment rights.

A federal judge in Portland had blocked the law in February of 2025, saying the gun rights groups would likely succeed after establishing irreparable injury.

The 1st U.S. Circuit Court of Appeals in Boston disagreed, ruling in April of this year the law is likely constitutional. It determined the waiting period does not block people from owning guns and only slows down the process.

Monday’s Supreme Court decision to not take up the case came with the release of dozens of other cases the court declined to hear.  No reasoning was offered in any of the cases, which is not unusual.