In carrying out the mandate of 18 U.S.C. § 3553(a) to impose a sentence that is "sufficient but not greater than necessary on a defendant," may a district court consider reports generated by the United States Sentencing Commission's own advisory groups that concluded that the Guidelines for aggravated assault create sentencing inequities for Native American defendants?

Whether a district court may consider reports generated by the United States Sentencing Commission's advisory groups that concluded the Guidelines for aggravated assault create sentencing inequities for Native American defendants when imposing a sentence under 18 U.S.C. § 3553(a)