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Although the Supreme Court decided United States v. Windsor on equal protection grounds, that case also raised important and recurring questions about federal power. In particular, defenders of the Defense of Marriage Act (DOMA) argued that Congress may always define the terms used in federal statutes, even if its definition concerns a matter reserved to the States. As the DOMA illustrates, federal definitions concerning reserved matters that depart from state law may impose significant burdens on state governments and private citizens alike. This Article argues that there is no general, freestanding federal definitions power and that sometimes—as with marriage—federal law must incorporate state law definitions.

Library of Congress Subject Headings

Constitutional law, Federal government, Delegation of powers, Defense of Marriage Act, Same-sex marriage—Law and legislation