CHEVRON U.S. A. v. NATURAL RES. DEF. COUNCIL

467 U.S. 837

Argued: February 29, 1984    Decided: June 25, 1984

STEVENS, J., delivered the opinion of the Court, in which all other Members joined, except MARSHALL and REHNQUIST, JJ., who took no part in the consideration or decision of the cases, and O'CONNOR, J., who took no part in the decision of the cases.

In the Clean Air Act Amendments of 1977, Pub. L. 95-95, 91 Stat. 685, Congress enacted certain requirements applicable [467 U.S. 837, 840]  to States that had not achieved the national air quality standards established by the Environmental Protection Agency (EPA) pursuant to earlier legislation. The amended Clean Air Act required these "nonattainment" States to establish a permit program regulating "new or modified major stationary sources" of air pollution. Generally, a permit may not be issued for a new or modified major stationary source unless several stringent conditions are met. 1 The EPA regulation promulgated to implement this permit requirement allows a State to adopt a plantwide definition of the term "stationary source." 2 Under this definition, an existing plant that contains several pollution-emitting devices may install or modify one piece of equipment without meeting the permit conditions if the alteration will not increase the total emissions from the plant. The question presented by these cases is whether EPA's decision to allow States to treat all of the pollution-emitting devices within the same industrial grouping as though they were encased within a single "bubble" is based on a reasonable construction of the statutory term "stationary source."

I

The EPA regulations containing the plantwide definition of the term stationary source were promulgated on October [467 U.S. 837, 841]  14, 1981. 46 Fed. Reg. 50766. Respondents 3 filed a timely petition for review in the United States Court of Appeals for the District of Columbia Circuit pursuant to 42 U.S.C. 7607(b) (1). 4 The Court of Appeals set aside the regulations. National Resources Defense Council, Inc. v. Gorsuch, 222 U.S. App. D.C. 268, 685 F.2d 718 (1982).

The court observed that the relevant part of the amended Clean Air Act "does not explicitly define what Congress envisioned as a `stationary source, to which the permit program . . . should apply," and further stated that the precise issue was not "squarely addressed in the legislative history." Id., at 273, 685 F.2d, at 723. In light of its conclusion that the legislative history bearing on the question was "at best contradictory," it reasoned that "the purposes of the nonattainment program should guide our decision here." Id., at 276, n. 39, 685 F.2d, at 726, n. 39. 5 Based on two of its precedents concerning the applicability of the bubble concept to certain Clean Air Act programs, 6 the court stated that the bubble concept was "mandatory" in programs designed merely to maintain existing air quality, but held that it was "inappropriate" in programs enacted to improve air quality. Id., at 276, 685 F.2d, at 726. Since the purpose of the permit [467 U.S. 837, 842]  program - its "raison d'etre," in the court's view - was to improve air quality, the court held that the bubble concept was inapplicable in these cases under its prior precedents. Ibid. It therefore set aside the regulations embodying the bubble concept as contrary to law. We granted certiorari to review that judgment, 461 U.S. 956 (1983), and we now reverse.

The basic legal error of the Court of Appeals was to adopt a static judicial definition of the term "stationary source" when it had decided that Congress itself had not commanded that definition. Respondents do not defend the legal reasoning of the Court of Appeals. 7 Nevertheless, since this Court reviews judgments, not opinions, 8 we must determine whether the Court of Appeals' legal error resulted in an erroneous judgment on the validity of the regulations.

II

When a court reviews an agency's construction of the statute which it administers, it is confronted with two questions. First, always, is the question whether Congress has directly spoken to the precise question at issue. If the intent of Congress is clear, that is the end of the matter; for the court, [467 U.S. 837, 843]  as well as the agency, must give effect to the unambiguously expressed intent of Congress. 9 If, however, the court determines Congress has not directly addressed the precise question at issue, the court does not simply impose its own construction on the statute, 10 as would be necessary in the absence of an administrative interpretation. Rather, if the statute is silent or ambiguous with respect to the specific issue, the question for the court is whether the agency's answer is based on a permissible construction of the statute. ¹¹

"The power of an administrative agency to administer a congressionally created . . . program necessarily requires the formulation of policy and the making of rules to fill any gap left, implicitly or explicitly, by Congress." Morton v. Ruiz, 415 U.S. 199, 231 (1974). If Congress has explicitly left a gap for the agency to fill, there is an express delegation [467 U.S. 837, 844]  of authority to the agency to elucidate a specific provision of the statute by regulation. Such legislative regulations are given controlling weight unless they are arbitrary, capricious, or manifestly contrary to the statute.¹² Sometimes the legislative delegation to an agency on a particular question is implicit rather than explicit. In such a case, a court may not substitute its own construction of a statutory provison î for a reasonable interpretation made by the administrator of an agency.¹³ 

We have long recognized that considerable weight should be accorded to an executive department's construction of a statutory scheme it is entrusted to administer, 14 and the principle of deference to administrative interpretations "has been consistently followed by this Court whenever decision as to the meaning or reach of a statute has involved reconciling conflicting policies, and a full understanding of the force of the statutory policy in the given situation has depended upon more than ordinary knowledge respecting the matters subjected to agency regulations. See, e. g., National Broadcasting Co. v. United States, 319 U.S. 190 ; Labor Board v. Hearst Publications, Inc., 322 U.S. 111 ; Republic Aviation Corp. v. [467 U.S. 837, 845]  Labor Board, 324 U.S. 793 ; Securities & Exchange Comm'n v. Chenery Corp., 332 U.S. 194 ; Labor Board v. Seven-Up Bottling Co., 344 U.S. 344 .

". . . If this choice represents a reasonable accommodation of conflicting policies that were committed to the agency's care by the statute, we should not disturb it unless it appears from the statute or its legislative history that the accommodation is not one that Congress would have sanctioned." United States v. Shimer, 367 U.S. 374, 382 , 383 (1961).

Accord, Capital Cities Cable, Inc. v. Crisp, ante, at 699-700.

In light of these well-settled principles it is clear that the Court of Appeals misconceived the nature of its role in reviewing the regulations at issue. Once it determined, after its own examination of the legislation, that Congress did not actually have an intent regarding the applicability of the bubble concept to the permit program, the question before it was not whether in its view the concept is "inappropriate" in the general context of a program designed to improve air quality, but whether the Administrator's view that it is appropriate in the context of this particular program is a reasonable one. Based on the examination of the legislation and its history which follows, we agree with the Court of Appeals that Congress did not have a specific intention on the applicability of the bubble concept in these cases, and conclude that the EPA's use of that concept here is a reasonable policy choice for the agency to make.

* * *

The judgment of the Court of Appeals is reversed.

It is so ordered.

JUSTICE MARSHALL and JUSTICE REHNQUIST took no part in the consideration or decision of these cases. JUSTICE O'CONNOR took no part in the decision of these cases.