Per Curiam
describes. See 540 U. S., at 455. We need not overrule Robinson or Smith to characterize Rules 33 and 45 as claim-processing rules.
In Smith, the District Judge rejected a Rule 33 motion for new trial, and the conviction was affirmed on appeal. 331 U. S., at 470. After the defendant was taken into custody, the District Judge changed his mind. Purporting to act under the authority of Rule 33, he issued an order vacating his earlier judgment and granting a new trial. Id., at 471. Although we observed in a footnote that "[t]he policy of the Rules was not to extend power indefinitely but to confine it within constant time periods," id., at 473–474, n. 2, that observation hardly transforms the Rules into the keys to the kingdom of subject-matter jurisdiction. Rather, as we emphasized in the text, the District Judge could not use Rule 33 to sidestep a pre-existing basic principle of judicial process—that once a final judgment is issued and the court of appeals considers a case, a district court has no power to act on it further. This was a consequence, however, not of the Rule, but of the Rule's failure to alter prior law. Smith does not address the effect of untimely arguments in support of a motion for new trial when, as here, the district court is still considering post-trial motions and the case has not yet been appealed.
Nor does Robinson address that circumstance. Defendants were 11 days late in filing their notices of appeal under (what was then) Rule 37. The Government responded not by contesting the merits of the appeal, but by moving to dismiss on the basis of untimeliness. 361 U. S., at 221. The Court of Appeals determined that if the District Court found that the untimely notices of appeal sprang from "excusable neglect," it could allow the appeals. On remand, the District Court so found. Id., at 222. We held that the Court of Appeals was wrong in having failed to dismiss under Rule 45(b). Id., at 229–230. Robinson is correct not because the District Court lacked
