The Clean Air Act required states with nonattainment areas to establish permit programs regulating new or modified major stationary sources of air pollution. After the 1977 amendments, the EPA adopted a regulation allowing states to treat all pollution-emitting devices within the same industrial plant as a single "stationary source" under the "bubble concept." Natural Resources Defense Council challenged that rule, arguing that each individual smokestack or pollution-emitting device had to be treated as a separate source. The court of appeals invalidated the EPA’s regulation, concluding that the Act required a different reading.
When a statute administered by an agency is ambiguous, must a court defer to the agency’s reasonable interpretation of the statute?
If Congress has directly spoken to the precise question at issue, both courts and agencies must give effect to Congress’s unambiguously expressed intent. But if the statute is silent or ambiguous on the specific issue, a court should defer to the agency’s interpretation so long as it is reasonable.
Yes. The Court held that the term "stationary source" was ambiguous in the Clean Air Act and that EPA’s plantwide definition was a permissible construction of the statute. The EPA’s use of the bubble concept was therefore upheld.
Justice Stevens announced a now-famous two-step framework. First, the Court asks whether Congress has clearly resolved the precise issue; if so, that ends the matter. Second, if the statute is ambiguous, the question is whether the agency’s interpretation is based on a permissible construction, and EPA’s plantwide approach was reasonable because the Act’s text and policy did not compel a single-device definition and the agency could balance environmental and economic considerations. The Court also emphasized that agencies, rather than courts, are better positioned and politically accountable to make policy choices within statutory gaps.
Chevron is the canonical case establishing "Chevron deference," which for decades structured judicial review of agency statutory interpretations. It became a foundational administrative law precedent, often paired with Skidmore v. Swift & Co., 323 U.S. 134 (1944), United States v. Mead Corp., 533 U.S. 218 (2001), and National Cable & Telecommunications Ass'n v. Brand X Internet Services, 545 U.S. 967 (2005). Its central framework was later overruled as a mandatory doctrine in Loper Bright Enterprises v. Raimondo, 603 U.S. ___ (2024), which rejected Chevron deference and restored independent judicial judgment under the Administrative Procedure Act.
Skidmore v. Swift & Co., 323 U.S. 134 (1944) |
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United States v. Mead Corp., 533 U.S. 218 (2001) |
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National Cable & Telecommunications Ass'n v. Brand X Internet Services, 545 U.S. 967 (2005) |
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