Document Type
Article
Publication Date
2026
Abstract
This Essay argues that constitutional law’s treatment of fiscal federalism has fractured into a bewildering collection of doctrinal silos. Federal spending that pressures states, federal preemption of state taxes, the Dormant Commerce Clause, sovereign immunity, Section 5 of the Fourteenth Amendment, and the federal taxing power are all analyzed through distinct tests, even when they implicate the same basic conflict between federal authority and state fiscal autonomy. The result is not just theoretical confusion but inconsistent constitutional answers. Current doctrine can protect states from comparatively modest liabilities while leaving uncertain whether Congress may displace large swaths of state revenue authority.
We propose Fiscal Federalism Proportionality Review (FFPR) as a default organizing framework. FFPR asks courts to evaluate the asserted federal interest, the state interest at stake, the fit between the federal means and ends, and whether the federal benefit is proportional to the burden on state autonomy. We do not argue that every constitutional clause should be governed by the same test. Rather, where text, history, structure, or institutional function justify doctrinal divergence, courts should say so. FFPR supplies a presumption of symmetry and a demand for reason-giving, not sameness for its own sake.
The Essay applies FFPR to federal limits on state revenue power and to constitutional limits on federal fiscal power. We examine conditional spending, Commerce Clause preemption, the Internet Tax Freedom Act, Dormant Commerce Clause limits on state taxation, sovereign immunity, Congress’s Section 5 enforcement power, and the apportionment and uniformity requirements for federal taxation. Across these settings, FFPR offers a more coherent way to address both familiar disputes and emerging conflicts over digital taxation, wealth taxation, and other fiscal innovations. In an era of changing technology and renewed struggles over fiscal authority, constitutional doctrine needs a framework capable of principled flexibility.
Recommended Citation
David Gamage and Darien Shanske,
Against Doctrinal Siloing: Harmonizing Fiscal Federalism and the U.S. Constitution, 103 Washington University Law Review 1993
(2026).
Available at: https://scholarship.law.missouri.edu/facpubs/1382