Legislating <em>Chevron</em>

One of the most significant administrative law cases, Chevron v. Natural Resources Defense Council, lnc., is routinely referred to as the "counter-Marbury." The reference suggests that Chevron's command to courts to defer to certain reasonable agency interpretations of statutes is superficially an uneasy fit with the declaration in Marbury v. Madison that "[i]t is emphatically the province and duty of the judicial department to say what the law is." According to the consensus view, Chevron deference is consistent with Marbury, as long as Congress has delegated to agencies the power to make policy by interpreting ambiguous statutory language or filling gaps in regulatory laws. In saying what the law is, courts determine that the law demands deference to the agency's decision. As Henry Monaghan wrote before Chevron: "A statement that judicial deference is mandated to an administrative 'interpretation' of a statute is more appropriately understood as a judicial conclusion that some substantive law-making authority has been conferred upon the agency." His use of the passive tense here could obscure one important part of his formulation: It is Congress that has conferred such lawmaking power on the agencies; thus, judicial deference stems from an understanding that it is emphatically the province and duty of the legislative department to determine whether agencies or the courts should determine policy by interpreting statutes.