Conor Clark (Wash. U.) & Ari Glogower (Northwestern), The Indirect Taxes, 102 Notre Dame L. Rev. (forthcoming 2027)

Article I of the Constitution empowers Congress to “lay and collect Taxes, Duties, Imposts and Excises.” It is arguably Congress’s most important power. A government’s first task is to fund itself, and the absence of an enforceable funding mechanism under the Articles of Confederation was a primary reason for the Constitution in the first place. Yet scholarly and judicial attention has focused mostly on the term “taxes” (and specifically what constitutes a “direct tax” that must be apportioned) while largely overlooking the three terms that follow—the duties, imposts, and excises that are collectively known as the “indirect taxes.” 

While poorly understood, these indirect taxes are critical to determining the overall scope of the taxing power. The Supreme Court has always treated a tax as either direct or indirect, with nothing in between. Because apportioned direct taxes are generally considered unworkable, the scope of indirect taxation defines what Congress can realistically do—an issue the Court left conspicuously open in Moore v. United States.

This Article offers a comprehensive new account of the indirect taxes, grounded in evidence that has gone largely unexplored: the hundreds of late-eighteenth- and nineteenth-century statutes in which Congress expressly enacted and modified indirect taxes—laws far outnumbering the handful ever apportioned as direct taxes. We use that evidence to construct a positive account of what Congress did and can tax, rather than what it cannot.

The indirect tax practice reveals a wider understanding of the taxing power than has been appreciated. From the beginning (and without constitutional controversy), Congress used duties, imposts, and excises as malleable, overlapping tools, continually adapted to a changing economy. Innovations that might be treated as contested outliers or recent inventions—unapportioned taxes on property, income, and broad classes of business activity—in fact sit squarely within a long and continuous practice. This account undercuts the view that the taxing power should be cabined by formalistic distinctions between economically similar tax instruments and offers precedent for further evolution concerning the most pressing tax questions of today.