18 U.S.C. App. (FEDERAL RULES OF CRIMINAL PROCEDURE) Rule 33

(a) Defendant’s Motion. Upon the defendant’s motion, the court may vacate any judgment and grant a new trial if the interest of justice so requires. If the case was tried without a jury, the court may take additional testimony and enter a new judgment. (b) Time to File. (1) Newly Discovered Evidence. Any motion for a new trial grounded on newly discovered evidence must be filed within 3 years after the verdict or finding of guilty. If an appeal is pending, the court may not grant a motion for a new trial until the appellate court remands the case. (2) Other Grounds. Any motion for a new trial grounded on any reason other than newly discovered evidence must be filed within 14 days after the verdict or finding of guilty.