United States Environmental Protection Agency v. Natural Resources Defense Council, Inc.

Opinion summary

Etalia.ai summary of the majority opinion

The case involved the United States Environmental Protection Agency (EPA) and its interpretation of a provision in the Clean Air Act regarding 'stationary sources' of air pollution. The EPA adopted a regulation allowing states to treat an entire plant as a single source, rather than each individual emission point within the plant, for purposes of meeting national air quality standards. This approach was challenged by the Natural Resources Defense Council (NRDC), which argued that it allowed plants to increase emissions without proper oversight. The Supreme Court ruled in favor of the EPA, establishing what is now known as Chevron deference—a legal principle mandating that courts defer to agency interpretations of ambiguous statutes if they are reasonable. This decision underscored judicial respect for administrative expertise and discretion when statutory language is unclear.