Whether the standard for appellate review of a Second Amendment claim raised before a sentencing proceeding and decided on the merits by the district court over a Rule 12 waiver objection by the government, is subject to de novo review, as Petitioner claimed, or is waived because of alleged untimeliness under Rule 12 as the First Circuit held, or is subject to plain error review as every circuit (including the First Circuit in other cases) has repeatedly held as to claims not made in the trial court.

Whether the standard for appellate review of a Second Amendment claim raised before a sentencing proceeding and decided on the merits by the district court over a Rule 12 waiver objection by the government, is subject to de novo review, as Petitioner claimed, or is waived because of alleged untimeliness under Rule 12 as the First Circuit held, or is subject to plain error review as every circuit (including the First Circuit in other cases) has repeatedly held as to claims not made in the trial court