"President Trump said Wednesday his administration is revoking a waiver that allowed California to set its own standards for automobile emissions." https://www.npr.org/2019/09/18/761815991/white-house-to-revoke-waiver-allowing-california-to-set-its-own-emissions-standa

Why does any state need an EPA waiver to set their own emission standards? States and counties have the power to enforce safety and emission inspections, vehicle noise ordinances, no-idling laws, etc. Why are emission standards not a states' right?

  • 6
    I'm guessing it has something to do the Commerce clause "During the post-1937 era, the use of the Commerce Clause by Congress to authorize federal control of economic matters became effectively unlimited." Sep 19, 2019 at 15:48
  • Why does a State need Federal Government permission to act on illegal immigration? Sep 19, 2019 at 18:19
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    Basically, it's a case of federal preemption.
    – Kevin
    Sep 19, 2019 at 22:28
  • Just imagine the chaos of having to comply with 50 different regulations. It would be extremely bad for businesses Sep 20, 2019 at 20:00

1 Answer 1


Why does a state need a waiver to set emission standards?

Mostly, to prevent costly, repetitive litigation. There are literally 100s of cases where state laws have been challenged in federal court for creating a burden on interstate commerce1; including, for example, mudguards on trucks (Bibb v. Navajo Freight Lines, 359 U.S. 520 (1959).) and the number of freight cars on trains (Southern Pacific Co. v. Arizona ex rel. Sullivan,325 U.S. 761 (1945).) These cases occurred in the absence of Federal regulation.

In the case of emissions, Congress passed the Clean Air Act of 1963 to establish uniform regulations for the United States.

It was first amended in 1965, by the Motor Vehicle Air Pollution Control Act, which authorized the federal government to set required standards for controlling the emission of pollutants from certain automobiles, beginning with the 1968 models.

In doing so Congress specifically preempted1 states from passing their own regulations in the absence of federal approval. The first waiver was granted in 1968 for model year 1969.

July 16, 1968, Volume 33, Number 137, pg. 10160 - Department of Health, Education, and Welfare; Office of the Secretary; Motor Vehicle Pollution Control; California State Standards; Waiver of Application of Section 208, Clean Air Act

Waiver Process

The Clean Air Act allows California to seek a waiver of the preemption which prohibits states from enacting emission standards for new motor vehicles. EPA must grant a waiver, however, before California’s rules may be enforced. When California files a waiver request, EPA publishes a notice for public hearing and written comment in the Federal Register. The written comment period remains open for a period of time after the public hearing. Once the comment period expires, EPA reviews the comments and the Administrator determines whether the requirements for obtaining a waiver have been met.

States and counties have the power to enforce safety and emission inspections, vehicle noise ordinances, no-idling laws, etc.

Not entirely. Vehicle inspection in the United States:

In the United States, vehicle safety inspection and emissions inspection are governed by each state individually. ...

The Clean Air Act of 1990 required some states to enact vehicle emissions inspection programs.

The EPA monitors Anti-Idling Regulations and may choose to act if they find a reason.

On vehicle noise, see Noise Pollution and Abatement Act of 1972:

The Act established mechanisms of setting emission standards for virtually every source of noise, including motor vehicles, ...

Congress ended funding of the federal noise control program in 1981, which curtailed development of further national regulations. Since then, starting in 1982, the primary responsibility to addressing noise pollution shifted to state and local governments.

1 Mentioned in a comment.

  • Rick, thank you for the great answer. If I understand correctly, auto regulations that vary state-by-state (e.g. maximum frame height) could potentially be regulated at a federal level if they proved to be excessively burdensome. But since they don't affect enough people and businesses, they remain up to the states, and it's up the manufacturers to market to customers that can use their products. Is that the gist of it? Sep 20, 2019 at 20:30
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    But why is the Fed government challenging state actions? It's using interstate commerce as the method to so, but the reason is: states overstepping their boundaries to the point that they make policies for the whole Union.T he point at which an exercise of state power (by a state or group of states) infringes on the right to self-government of the citizens of the other states Read about it here. baseballcrank.com/archives2/2003/04/law_federalisms_1.php
    – user9790
    Sep 20, 2019 at 20:59

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