Can a panel review the sufficiency of the evidence only for plain error?

5 The government argues that the panel is limited to reviewing the sufficiency of the evidence for plain error. Although the defendants did move for an acquittal at the conclusion of the government's case, the government alleges that they failed to move for an acquittal at the conclusion of the evidence or after the discharge of the jury. United States v. Mora, 876 F.2d 76, 77 (9th Cir.1989) (reviewing sufficiency of the evidence only for plain error because defense counsel failed to renew motion for acquittal). Because we believe that the defendants' arguments fail under either standard, we express no opinion on this issue.