In what circumstances will the court allow a prosecutor to argue their case before the jury?

A decent regard for the rights of defendants in a criminal trial, particularly in a complex case where argument as to the admissibility of evidence, especially its relevance, is bound to involve assertions by the prosecutor as to how the evidence bears upon the issue that the jury must decide and what it will prove to the jury, should lead the court to incline toward holding such arguments out of the presence of the jury. This can be done either at the bench or by excusing the jury, and in either event, it is perfectly possible to make a record of the colloquy so that the rights of the parties will be protected. (See Eierman v. United States, 10 Cir., 1930, 46 F.2d 46.)

Nevertheless, it is clear that the court has a discretion in this matter. (Holt v. United States, 1910, 218 U.S. 245, 249-250, 31 S.Ct. 2, 54 L.Ed. 1021.) We have carefully examined each instance in which such a colloquy before the jury occurred, and while we think that in one or two instances the court's comments on the respective contentions of the parties should have been less sharp than they were, and that one or two of them were unfortunate in that they brought before the jury matters that it would be better that they had not heard, we cannot find that any of them, or all of them together, were prejudicial, especially in view of the instructions that the court repeatedly gave the jury.