short of holding that the Constitution requires a hearing on voluntariness to be held sua sponte. Id. at 847. It instead held that, “in supervising the administration of justice in federal courts, we, too, have an obligation to protect the rights of the accused and to preserve the orderly functioning of trial courts.... Thus, as an exercise of the federal courts’ judicial authority to use their remedial mechanisms to redress or obviate ... constitutional injuries, we remand to the district court for a hearing on the issue of the voluntariness of any of appellant’s alleged statements.” Id. at 847-48. (quotation omitted). The holding of Powe is therefore based not on a constitutional re , 119 F.3d 1393 (9th Cir.1997); United States v. Bentley, 726 F.2d 1124, 1128-29 (6th Cir.1984) (<HOLDING>); Powe, 591 F.2d at 844 (D.C.Cir.1978); United
holding that in determining the voluntariness of a waiver of miranda rights a court must evaluate the totality of the circumstances holding that trial court committed plain error by not determining the voluntariness of the defendants miranda waiver when the evidence clearly reflected such an issue holding that the trial court need not hold a voluntariness hearing where the defendant did not object and no evidence presented raised the issue holding that plain error exists when 1 an error was committed 2 that was plain 3 that affected the defendants substantial rights and 4 the error seriously affects the fairness integrity or public reputation of judicial proceedings holding that defendants failure to appeal the voluntariness of a plea constitutes waiver of the issue on subsequent appeal