## Facts

- The Clean Air Act generally preempts state motor-vehicle emission controls, but § 209 directs EPA to waive preemption for California unless specified statutory grounds for denial are found.
- California adopted regulations limiting scheduled maintenance manufacturers could perform during prototype durability testing for certification.
- California also adopted “in-use maintenance” regulations limiting the maintenance manufacturers could require purchasers to perform in written maintenance instructions provided with new vehicles sold in California.
- Under California’s approach, manufacturers could not require in-use maintenance exceeding what they were permitted to perform during certification testing.
- California requested a § 209 waiver so these in-use maintenance requirements could be enforced.
- In July 1978, EPA granted California a waiver of federal preemption for the in-use maintenance regulations.
- Multiple industry associations and manufacturers petitioned for review, arguing the waiver exceeded § 209, conflicted with § 207 (warranties and maintenance instructions), and was arbitrary and capricious; some petitioners also asserted antitrust-related objections.

## Issues

1. Whether Clean Air Act § 209 authorizes EPA to waive preemption for California requirements that function as accompanying enforcement procedures or conditions of sale, including in-use maintenance limits.
2. Whether California’s in-use maintenance regulations are barred because they conflict with the federal warranty and maintenance-instruction scheme in Clean Air Act § 207.
3. Whether EPA’s waiver decision was arbitrary, capricious, an abuse of discretion, or otherwise not in accordance with law, including for alleged failure to consider antitrust implications.

## Decision

- The court denied the petitions for review and upheld EPA’s waiver decision.
- The court held that § 209 empowers EPA to waive preemption for California’s accompanying enforcement procedures, including in-use maintenance regulations tied to certification and sale.
- The court found no statutory conflict requiring invalidation of the waiver based on § 207.
- Applying APA review, the court concluded the Administrator’s decision was not arbitrary or capricious.
- The court rejected the argument that the waiver was unlawful for failure to address antitrust concerns beyond the § 209 criteria.

## Legal Principles

- Under Clean Air Act § 209, EPA must grant California a waiver of federal preemption for its motor-vehicle emissions control program—including related enforcement procedures and conditions precedent to initial retail sale—unless the statutory bases for denial are established.
- In-use maintenance limits that constrain manufacturers’ required consumer maintenance to what was permitted during certification may qualify as accompanying enforcement procedures within § 209’s waiver scope.
- A § 209 waiver is reviewed under the APA’s arbitrary-and-capricious standard; courts assess statutory authority, consideration of relevant factors, and reasoned explanation rather than substituting policy judgment.
- Clean Air Act § 207 does not, by itself, categorically preclude California (once a waiver is granted) from imposing additional requirements related to maintenance instructions as part of its emissions control enforcement scheme.

## Conclusion

The D.C. Circuit upheld EPA’s § 209 waiver for California’s in-use maintenance regulations, concluding the waiver fell within the statute’s authorization for accompanying enforcement procedures, did not impermissibly conflict with § 207, and was not arbitrary or capricious under the APA.


Motor & Equip. Mfrs. Ass'n v. EPA, 627 F.2d 1095 (D.C. Cir. 1979)