The State of Treasury Regulatory Authority After Mayo Foundation: Arguing for an Intentionalist Approach at Chevron Step One – Note by Joana Que

On January 11th, 2011, the Supreme Court unanimously held in Mayo Foundation for Medical Education and Research v. United States that all agency regulations, including Treasury regulations, should be afforded the standard of deference set out in Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc, a case that prescribed how courts should review agency regulations. Before Mayo, Chevron did not have very much influence in the tax world–Chevron had been cited in only a few Supreme Court tax cases, and the Tax Court continued to cite pre-Chevron authority when evaluating whether to defer to the Treasury’s construction of the Internal Revenue Code (“Tax Code”). Thus, the Mayo decision superseded a line of tax cases, including National Muffler Dealers Ass’n v. United States, which had established a less deferential, tax-specific standard of review.