What is the current state of the law on prosecutorial misconduct?

The defendants allege various instances of prosecutorial misconduct during their trial. This court previously has stated that "[p]rompt and effective action by the trial court may neutralize the damage by admonition to counsel or by appropriate curative instructions to the jury, but prosecutorial misconduct invites reversal if it appears more probable than not that the alleged misconduct affected the jury's verdict." United States v. Simtob, 901 F.2d 799, 806 (9th Cir.1990) (citation omitted).

"Ordinarily cautionary instructions are sufficient to cure the effects of improper comments." United States v. Davis, 932 F.2d 752, 761 (9th Cir.1991). "Even where no curative instruction is given, or the instruction is insufficient to cure the prejudicial impact of the impropriety, the court should 'not reverse a defendant's conviction if substantial, independent and credible evidence of the defendant's guilt overwhelms whatever incriminating aspects inadmissible statements may have had in isolation.' " Id. (citation omitted).