Rosales-Mireles did not object to the error in the District Court, which relied on the miscalculated Guidelines range and sentenced him to 78 months of imprisonment. On appeal, Rosales-Mireles challenged the incorrect Guidelines range for the first time. The Fifth Circuit found that the Guidelines error was plain and that it affected Rosales-Mireles’ substantial rights because there was a “reasonable probability that he would have been subject to a different sentence but for the error.” The Fifth Circuit nevertheless declined to remand the case for resentencing, concluding that Rosales-Mireles had not established that the error would seriously affect the fairness, integrity, or public reputation of judicial proceedings because neither the error nor the resulting sentence “would shock the conscience.”
A miscalculation of a Guidelines sentencing range that has been determined to be plain and to affect a defendant’s substantial rights calls for a court of appeals to exercise its discretion under Rule 52(b) to vacate the defendant’s sentence in the ordinary case. Although “Rule 52(b) is permissive, not mandatory,” Olano, 507 U. S., at 735, it is well established that courts “should” correct a forfeited plain error affecting substantial rights “if the error ‘seriously affects the fairness, integrity or public reputation of judicial proceedings,’ ” id., at 736. Like the narrow rule rejected in Olano, which would have called for relief only for a miscarriage of justice, the Fifth Circuit’s shock-the-conscience standard too narrowly confines the extent of the court of appeals’ discretion.
It is not reflected in Rule 52(b), nor in how the plain-error doctrine has been applied by this Court, which has reversed judgments for plain error based on inadvertent or unintentional errors by the court or the parties below and has remanded cases involving such errors, including sentencing errors, for consideration of Olano’s fourth prong. The errors are not required to amount to a “powerful indictment” of the system.
Had the lower court’s ruling been upheld, the alternative path for the petitioner would have been to pursue an ineffective assistance of counsel claim. That would have been a strong claim even when viewed through the lens of the lower court since no one disputes that trial counsel missed the double counting of a prior conviction and that error almost certainly led to a longer sentence than would have otherwise been handed down.