The Clean Air Act (CAA) is a persistent source of federal-state conflict. Like many federal environmental laws, the CAA relies upon the cooperation of state environmental agencies for its execution and enforcement. To induce such cooperation, the CAA authorizes, even requires, the imposition of sanctions on noncooperating states, including the loss of federal highway funds. NFIB v. Sebelius, however, casts doubt on the constitutionality of the CAA’s sanction regime. Specifically, NFIB enforced limits on the use of conditional spending to induce state cooperation with a federal program and held that Congress may not use conditional spending to “coerce” state cooperation. Combined with South Dakota v. Dole, NFIB provides objecting states with a powerful set of arguments that the CAA highway fund sanctions are unconstitutional, and suggests potential challenges to other CAA sanction provisions as well.


Clean Air Act, State Implementation Plans, Conditional Spending, NFIB v. Sebelius, Federalism, Highway Sanctions, Federal Highway Trust Fund, South Dakota v. Dole, Spending

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Place of Original Publication

Ecology Law Quarterly

Publication Information

43 Ecology Law Quarterly 671 (2016)


COinS Jonathan Adler Faculty Bio