In United States v. Olano, 507 U.S. 725 (1993), the United States Supreme Court reviewed the Ninth Circuit's holding that the presence of alternate jurors during jury deliberations was "inherently prejudicial" and reversible per se, thereby satisfying the plain error doctrine. Olano at 730-31. The Court clarified the standard for plain error review of forfeited errors under Rule 52(b), laying out the four-prong test articulated above. Id. As to the third prong, the Court held that "normally, although perhaps not in every case, the defendant must make a specific showing of prejudice to satisfy the 'affecting substantial rights' prong of Rule 52(b)." Id. at 735. The Court then explained that Rule 52(b) is permissive, not mandatory: "If the forfeited error is 'plain' and 'affects substantial rights,' the court of appeals has authority to order correction, but is not required to do so." Id. The standard that should guide the exercise of discretion under Rule 52(b) is that the court "should correct a plain forfeited error affecting substantial rights if the error 'seriously affects the fairness, integrity or public reputation of judicial proceedings.'" Id. at 736. The Court explained that to avoid forfeiture under the plain error rule, three requirements must be met: error must have occurred; the error was plain, i.e., clear or obvious; and the plain error affected substantial rights. The third requirement generally requires a showing of prejudice, i.e., that the error affected the outcome of the lower court proceedings. Id., at 734. "It is the defendant rather than the Government who bears the burden of persuasion with respect to prejudice." Id. Finally, once a defendant satisfies these three requirements, an appellate court must exercise its discretion in deciding whether to reverse. Reversal is warranted only when the plain, forfeited error resulted in the conviction of an actually innocent defendant or when an error "'seriously affected the fairness, integrity or public reputation of judicial proceedings' independent of the defendant's innocence." Olano, 507 U.S. at 736-737. The United States Supreme Court observed that there may be a "special category of forfeited errors that can be corrected regardless of their effect on the outcome." Id. at 735. There, the court explained that Rule 52(b) allows a reviewing court to exercise its discretion and notice a forfeited error "'in those circumstances in which a miscarriage of justice would otherwise result'"--that is, where the defendant is actually innocent. 507 U.S. at 736, (quoting United States v. Young, 470 U.S. 1, 15, 105 S. Ct. 1038, 84 L. Ed. 2d 1 (1985)). But the court acknowledged that plain error is not limited to cases where the putative error causes the conviction of an innocent person; it also applies to cases where the putative error affects the fairness or integrity of the trial. Id. The Court suggested that the affecting-substantial-rights analysis was the "harmless error" analysis with one important difference: "When the defendant has made a timely objection to an error and Rule 52(a) applies, a court of appeals normally engages in a specific analysis of the district court record--a so-called "harmless error" inquiry--to determine whether the error was prejudicial. Rule 52(b) normally requires the same kind of inquiry, with one important difference: It is the defendant rather than the Government who bears the burden of persuasion with respect to prejudice." (507 U.S. at 734.)