When evaluating whether a sentence imposed within the applicable guideline range avoids unwarranted sentencing disparities under 18 U.S.C. § 3553(a)(6), may a court categorically refuse to consider empirical evidence showing that other judges impose sentences below the guideline range in the vast majority of cases in which the guideline applies, or showing that the guideline itself embodies structural disparities?

Whether a court may categorically refuse to consider empirical evidence showing that other judges impose sentences below the guideline range in the vast majority of cases in which the guideline applies, or showing that the guideline itself embodies structural disparities