Courts and commentators have long understood dormant Commerce Clause doctrine to contain two types of cases: discrimination and undue burdens. This Article argues for a more nuanced understanding that divides undue burdens into single-state burdens—which arise from the application of a single state’s law alone—and mismatch burdens, which arise from legal diversity. Although the Supreme Court purports to apply Pike balancing in all undue-burden cases, we show that the Court’s approach in mismatch cases differs substantially. Specifically, unlike in single-state cases, balancing in mismatch cases involves an implicit and potentially problematic comparison by the Court between the challenged state’s regulation and those of other states. We label analysis in mismatch cases “Bibb balancing,” after the famous mudflaps case, and we show that mismatch cases present the Court with a more challenging set of issues than do other types of dormant Commerce Clause cases. Despite the criticisms that attach to Bibb balancing, we recognize that failing to restrain regulatory mismatches would threaten the smooth functioning of the national marketplace and undercut important federalism values. Thus, in addition to clarifying the doctrine and acknowledging the drawbacks of Bibb balancing, this Article provides advice for achieving more consistent and defensible results in mismatch cases.

Citation
Michael S. Knoll & Ruth Mason, Bibb Balancing: Regulatory Mismatches Under the Dormant Commerce Clause, 91 George Washington Law Review 1 (2023).