The False Modesty of Department of Revenue v. Davis: Disrupting the Dormant Commerce Clause Through the Traditional Public Function Doctrine

Abstract

In Department of Revenue v. Davis, the United States Supreme Court held that the Kentucky income tax statute and, by extension, other states' similar laws do not discriminate for purposes of the dormant Commerce Clause. By explicitly deferring to established practices and expectations, Davis is, at first blush, the kind of modest, pragmatic decision advocated today by many, including, most prominently, Chief Justice Roberts. However, on a second look, Davis has broad implications. Indeed, Davis disrupts the Court's preexisting dormant Commerce Clause doctrine by confirming the Roberts Court's use of the category to immunize government activity from dormant Commerce Clause scrutiny. Over two decades ago, in Garcia v. San Antonio Metropolitan Transit Authority, the Supreme Court rejected for Commerce Clause purposes the doctrine as unworkable. The Garcia Court's criticism remains persuasive today: There is no principled basis for determining when a government function is old enough to be or public enough to be public. Every government activity is traditional or becomes so. Given the breadth (indeed, the indeterminacy) of the category, that category, as affirmed in Davis, encompasses and gives dormant Commerce Clause protection to all governmental activities including tax-based subsidies the Court has previously stricken as impermissibly discriminating under the dormant Commerce Clause. As these previously stricken activities constitute functions, Davis logically protects them from dormant Commerce Clause scrutiny.