“Because persons protected by the Second Amendment can no longer be denied gun ownership due simply to past drug use—a practice inconsistent with this nation’s historical tradition on firearm regulation—any false statement by Mr. Biden concerning his status as having used a controlled substance no longer concerns’ any fact material to the lawfulness of the sale’ of a firearm’ 18 U.S.C. § 922(a)(6),” Biden’s attorneys wrote. “Quite simply, asking about Mr. Biden’s status as a user of a controlled status is constitutionally irrelevant to whether he can be denied his Second Amendment right to gun ownership.”