467 U.S. 837 (1984)
Chevron U.S.A., Inc. v.
Whether a court should defer to a federal agency's interpretation of a statute that it administers when the statute is ambiguous.
The Chevron deference is established, whereby a court must first determine if Congress has directly spoken to the precise question at issue; if so, the court and agency must give effect to Congress’s unambiguously expressed intent. If the statute is silent or ambiguous, the question for the court is whether the agency's answer is based on a permissible construction of the statute.
The Supreme Court held that courts should defer to agency interpretations of statutory mandates unless such interpretations are unreasonable. The EPA's 'bubble concept' was a permissible interpretation of the term 'stationary source' under the Clean Air Act Amendments.
Chevron is critically significant for its introduction of a legal framework that dictates how courts should handle statutory ambiguity concerning administrative agency interpretations. Chevron deference has profound implications on regulatory authority, granting agencies flexibility and power to interpret laws within their enforcement purview. For law students, understanding Chevron is key to navigating administrative law and appreciating the judiciary's reduced role in second-guessing administrative decision-making.