Yellow Transportation, Inc. v. Michigan

Michigan (defendant) had a reciprocity policy waiving vehicle registration fees for interstate carriers registered in states that reciprocally waived fees for Michigan-registered vehicles, benefiting Yellow Transportation (plaintiff). Congress's ISTEA later created a single-state registration system capping per- vehicle fees at the level each state charged as of November 15, 1991, and the ICC's implementing regulations required states to cap fees at the level charged under their existing reciprocity agreements. Michigan then altered its reciprocity agreement and began charging Yellow Transportation fees, and Yellow Transportation sued, arguing this violated the ISTEA's fee cap as the ICC had interpreted it. Michigan's courts split, with the Michigan Supreme Court ultimately ruling that the state need not follow the ICC's interpretation.

Whether, under administrative law, states must enforce federal agency regulations that reflect the agency's reasonable interpretation of an ambiguous federal statute.