A court can supplement a jury instruction, to correct an omission, without prejudicing a defendant. A federal grand jury returned an indictment that charged the defendant, Wilner Castelin, with conspiracy to distribute and to possess, with intent to distribute Oxycodone and also with conspiracy to launder monetary instruments. After the parties presented evidence and closing arguments, the jury deliberated and asked the court whether the defendant was required to know that the substance was Oxycodone, as opposed to any other controlled substance that appears in a pill form. The court consulted with the prosecutor and defense counsel and reviewed three 2nd Circuit cases. The court charged the jury that to prevail the government had to prove that the defendant knew the substance was Oxycodone. The court then amended its charge and instructed the jury that to prevail, the government had to prove either that the defendant knew—or that it was reasonably foreseeable to the defendant—that the substance was Oxycodone. Jurors returned a guilty verdict, and the defendant filed a motion for a new trial, pursuant to Federal Rule of Criminal Procedure 33(a), which provides a court broad discretion to set aside a verdict and to order a new trial. The defendant argued that the court's decision to amend the jury instructions prejudiced the defendant. The 2nd Circuit's 1981 decision in U.S. v. Velez, which the defendant cited in support, was not directly on point, because the court's supplemental instruction to the jury in Velez omitted a crucial element of the definition of conspiracy. Here, in contrast, the court's supplemental instruction was correct and cured a deficiency in the earlier instruction. The defendant failed to establish prejudice that would lead to concern that an innocent person was convicted, and the District Court denied the defendant's motion for a new trial.