524 U.S. 125 (1998)

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR THE FIFTH CIRCUIT

[126] Breyer, J., delivered the opinion of the Court, in which Stevens, O'Connor, Kennedy, and Thomas, JJ., joined. Ginsburg, J., filed a dissenting opinion, in which Rehnquist, C. J., and Scalia and Souter, JJ., joined, post, p. 139.

Robert H. Klonoff argued the cause for petitioner in No. 96-1654. With him on the briefs were Gregory A. Castanias, Paul R. Reichert, and Ron S. Macaluso. Norman S. Zalkind, by appointment of the Court, 522 U. S. 1074, argued the cause for petitioners in No. 96-8837. With him on the briefs were Elizabeth A. Lunt, David Duncan, and John H. Cunha, Jr., by appointment of the Court, 522 U. S. 1074.

James A. Feldman argued the cause for the United States in both cases. With him on the brief were Solicitor General Waxman, Acting Assistant Attorney General Keeney, and Deputy Solicitor General Dreeben.^[2]

Justice Breyer, delivered the opinion of the Court.

A provision in the firearms chapter of the federal criminal code imposes a 5-year mandatory prison term upon a person who "uses or carries a firearm" "during and in relation to" a "drug trafficking crime." 18 U. S. C. § 924(c)(1). The question before us is whether the phrase "carries a firearm" is limited to the carrying of firearms on the person. We hold that it is not so limited. Rather, it also applies to a person [127] who knowingly possesses and conveys firearms in a vehicle, including in the locked glove compartment or trunk of a car, which the person accompanies.

I

The question arises in two cases, which we have consolidated for argument. Petitioner in the first case, Frank J. Muscarello, unlawfully sold marijuana, which he carried in his truck to the place of sale. Police officers found a handgun locked in the truck's glove compartment. During plea proceedings, Muscarello admitted that he had "carried" the gun "for protection in relation" to the drug offense, App. in No. 96-1654, p. 12, though he later claimed to the contrary, and added that, in any event, his "carr[ying]" of the gun in the glove compartment did not fall within the scope of the statutory word "carries." App. to Pet. for Cert. in No. 96-1654, p. 10a.

Petitioners in the second case, Donald Cleveland and Enrique Gray-Santana, placed several guns in a bag, put the bag in the trunk of a car, and then traveled by car to a proposed drug-sale point, where they intended to steal drugs from the sellers. Federal agents at the scene stopped them, searched the cars, found the guns and drugs, and arrested them.

In both cases the Courts of Appeals found that petitioners had "carrie[d]" the guns during and in relation to a drug trafficking offense. 106 F. 3d 636, 639 (CA5 1997); 106 F. 3d 1056, 1068 (CA1 1997). We granted certiorari to determine whether the fact that the guns were found in the locked glove compartment, or the trunk, of a car precludes application of § 924(c)(1). We conclude that it does not.

II

A

We begin with the statute's language. The parties vigorously contest the ordinary English meaning of the phrase [128] "carries a firearm." Because they essentially agree that Congress intended the phrase to convey its ordinary, and not some special legal, meaning, and because they argue the linguistic point at length, we too have looked into the matter in more than usual depth. Although the word "carry" has many different meanings, only two are relevant here. When one uses the word in the first, or primary, meaning, one can, as a matter of ordinary English, "carry firearms" in a wagon, car, truck, or other vehicle that one accompanies. When one uses the word in a different, rather special, way, to mean, for example, "bearing" or (in slang) "packing" (as in "packing a gun"), the matter is less clear. But, for reasons we shall set out below, we believe Congress intended to use the word in its primary sense and not in this latter, special way.

Consider first the word's primary meaning. The Oxford English Dictionary gives as its first definition "convey, originally by cart or wagon, hence in any vehicle, by ship, on horseback, etc." 2 Oxford English Dictionary 919 (2d ed. 1989); see also Webster's Third New International Dictionary 343 (1986) (first definition: "move while supporting (as in a vehicle or in one's hands or arms)"); Random House Dictionary of the English Language Unabridged 319 (2d ed. 1987) (first definition: "to take or support from one place to another; convey; transport").

The origin of the word "carries" explains why the first, or basic, meaning of the word "carry" includes conveyance in a vehicle. See Barnhart Dictionary of Etymology 146 (1988) (tracing the word from Latin "carum," which means "car" or "cart"); 2 Oxford English Dictionary, supra, at 919 (tracing the word from Old French "carier" and the late Latin "carricare," which meant to "convey in a car"); Oxford Dictionary of English Etymology 148 (C. Onions ed. 1966) (same); Barnhart Dictionary of Etymology, supra, at 143 (explaining that the term "car" has been used to refer to the automobile since 1896).

[129] The greatest of writers have used the word with this meaning. See, e. g., The King James Bible, 2 Kings 9:28 ("[H]is servants carried him in a chariot to Jerusalem"); id., Isaiah 30:6 ("[T]hey will carry their riches upon the shoulders of young asses"). Robinson Crusoe says, "[w]ith my boat, I carry'd away every Thing." D. Defoe, Robinson Crusoe 174 (J. Crowley ed. 1972). And the owners of Queequeg's ship, Melville writes, "had lent him a [wheelbarrow], in which to carry his heavy chest to his boarding-house." H. Melville, Moby Dick 43 (U. Chicago 1952). This Court, too, has spoken of the "carrying" of drugs in a car or in its "trunk." California v. Acevedo, 500 U. S. 565, 572-573 (1991); Florida v. Jimeno, 500 U. S. 248, 249 (1991).

These examples do not speak directly about carrying guns. But there is nothing linguistically special about the fact that weapons, rather than drugs, are being carried. Robinson Crusoe might have carried a gun in his boat; Queequeg might have borrowed a wheelbarrow in which to carry not a chest but a harpoon. And, to make certain that there is no special ordinary English restriction (unmentioned in dictionaries) upon the use of "carry" in respect to guns, we have surveyed modern press usage, albeit crudely, by searching computerized newspaper data bases—both the New York Times data base in Lexis/Nexis, and the "US News" data base in Westlaw. We looked for sentences in which the words "carry," "vehicle," and "weapon" (or variations thereof) all appear. We found thousands of such sentences, and random sampling suggests that many, perhaps more than one-third, are sentences used to convey the meaning at issue here, i. e., the carrying of guns in a car.

The New York Times, for example, writes about "an ex-con" who "arrives home driving a stolen car and carrying a load of handguns," Mar. 21, 1992, section 1, p. 18, col. 1, and an "official peace officer who carries a shotgun in his boat," June 19, 1988, section 12WC, p. 2, col. 1; cf. The New York [130] Times Manual of Style and Usage, a Desk Book of Guidelines for Writers and Editors, foreword (L. Jordan rev. ed. 1976) (restricting Times journalists and editors to the use of proper English). The Boston Globe refers to the arrest of a professional baseball player "for carrying a semiloaded automatic weapon in his car." Dec. 10, 1994, p. 75, col. 5. The Colorado Springs Gazette Telegraph speaks of one "Russell" who "carries a gun hidden in his car." May 2,1993, p. B1, col. 2. The Arkansas Gazette refers to a "house" that was "searched" in an effort to find "items that could be carried in a car, such as . . . guns."Mar. 10, 1991, p. A1, col. 2. The San Diego Union-Tribune asks, "What, do they carry guns aboard these boats now?" Feb. 18, 1992, p.D2, col. 5.

Now consider a different, somewhat special meaning of the word "carry"—a meaning upon which the linguistic arguments of petitioners and the dissent must rest. The Oxford English Dictionary's twenty-sixth definition of "carry" is "bear, wear, hold up, or sustain, as one moves about; habitually to bear about with one." 2 Oxford English Dictionary, at 921. Webster's defines "carry" as "to move while supporting," not just in a vehicle, but also "in one's hands or arms." Webster's Third New International Dictionary, supra, at 343. And Black's Law Dictionary defines the entire phrase "carry arms or weapons" as

"To wear, bear or carry them upon the person or in the clothing or in a pocket, for the purpose of use, or for the purpose of being armed and ready for offensive or defensive action in case of a conflict with another person." Black's Law Dictionary 214 (6th ed. 1990).

These special definitions, however, do not purport to limit the "carrying of arms" to the circumstances they describe. No one doubts that one who bears arms on his person "carries a weapon." But to say that is not to deny that one may also "carry a weapon" tied to the saddle of a horse or placed in a bag in a car.

[131] Nor is there any linguistic reason to think that Congress intended to limit the word "carries" in the statute to any of these special definitions. To the contrary, all these special definitions embody a form of an important, but secondary, meaning of "carry," a meaning that suggests support rather than movement or transportation, as when, for example, a column "carries" the weight of an arch. 2 Oxford English Dictionary, at 919, 921. In this sense a gangster might "carry" a gun (in colloquial language, he might "pack a gun") even though he does not move from his chair. It is difficult to believe, however, that Congress intended to limit the statutory word to this definition—imposing special punishment upon the comatose gangster while ignoring drug lords who drive to a sale carrying an arsenal of weapons in their van.

We recognize, as the dissent emphasizes, that the word "carry" has other meanings as well. But those other meanings (e. g., "carry all he knew," "carries no colours"), see post, at 143-144, are not relevant here. And the fact that speakers often do not add to the phrase "carry a gun" the words "in a car" is of no greater relevance here than the fact that millions of Americans did not see Muscarello carry a gun in his truck. The relevant linguistic facts are that the word "carry" in its ordinary sense includes carrying in a car and that the word, used in its ordinary sense, keeps the same meaning whether one carries a gun, a suitcase, or a banana.

Given the ordinary meaning of the word "carry," it is not surprising to find that the Federal Courts of Appeals have unanimously concluded that "carry" is not limited to the carrying of weapons directly on the person but can include their carriage in a car. United States v. Toms, 136 F. 3d 176, 181 (CADC 1998); United States v. Foster, 133 F. 3d 704, 708 (CA9 1998); United States v. Eyer, 113 F. 3d 470, 476 (CA3 1997); 106 F. 3d, at 1066 (case below); 106 F. 3d, at 639 (case below); United States v. Malcuit, 104 F. 3d 880, 885, rehearing en banc granted, 116 F. 3d 163 (CA6 1997); United States v. Mitchell, 104 F. 3d 649, 653-654 (CA4 1997); United [132] States v. Molina, 102 F. 3d 928, 932 (CA7 1996); United States v. Willis, 89 F. 3d 1371, 1379 (CA8 1996); United States v. Miller, 84 F. 3d 1244, 1259-1260 (1996), overruled on other grounds, United States v. Holland, 116 F. 3d 1353 (CA10 1997); United States v. Giraldo, 80 F. 3d 667, 676-677 (CA2 1996); United States v. Farris, 77 F. 3d 391, 395-396 (CA11 1996).

B

We now explore more deeply the purely legal question of whether Congress intended to use the word "carry" in its ordinary sense, or whether it intended to limit the scope of the phrase to instances in which a gun is carried "on the person." We conclude that neither the statute's basic purpose nor its legislative history support circumscribing the scope of the word "carry" by applying an "on the person" limitation.

This Court has described the statute's basic purpose broadly, as an effort to combat the "dangerous combination" of "drugs and guns." Smith v. United States, 508 U. S. 223, 240 (1993). And the provision's chief legislative sponsor has said that the provision seeks "to persuade the man who is tempted to commit a Federal felony to leave his gun at home." 114 Cong. Rec. 22231 (1968) (Rep. Poff); see Busic v. United States, 446 U. S. 398, 405 (1980) (describing Poff's comments as "crucial material" in interpreting the purpose of § 924(c)); Simpson v. United States, 435 U. S. 6, 13-14 (1978) (concluding that Poff's comments are "clearly probative" and "certainly entitled to weight"); see also 114 Cong. Rec. 22243-22244 (statutes would apply to "the man who goes out taking a gun to commit a crime") (Rep. Hunt); id., at 22244 ("Of course, what we are trying to do by these penalties is to persuade the criminal to leave his gun at home") (Rep. Randall); id. , at 22236 ("We are concerned . . . with having the criminal leave his gun at home") (Rep. Meskill).

From the perspective of any such purpose (persuading a criminal "to leave his gun at home"), what sense would it [133] make for this statute to penalize one who walks with a gun in a bag to the site of a drug sale, but to ignore a similar individual who, like defendant Gray-Santana, travels to a similar site with a similar gun in a similar bag, but instead of walking, drives there with the gun in his car? How persuasive is a punishment that is without effect until a drug dealer who has brought his gun to a sale (indeed has it available for use) actually takes it from the trunk (or unlocks the glove compartment) of his car? It is difficult to say that, considered as a class, those who prepare, say, to sell drugs by placing guns in their cars are less dangerous, or less deserving of punishment, than those who carry handguns on their person.

We have found no significant indication elsewhere in the legislative history of any more narrowly focused relevant purpose. We have found an instance in which a legislator referred to the statute as applicable when an individual "has a firearm on his person," ibid. (Rep. Meskill); an instance in which a legislator speaks of "a criminal who takes a gun in his hand," id. , at 22239 (Rep. Pucinski); and a reference in the Senate Report to a "gun carried in a pocket," S. Rep. No. 98-225, p. 314, n. 10 (1983); see also 114 Cong. Rec. 21788, 21789 (1968) (references to gun "carrying" without more). But in these instances no one purports to define the scope of the term "carries"; and the examples of guns carried on the person are not used to illustrate the reach of the term "carries" but to illustrate, or to criticize, a different aspect of the statute.

Regardless, in other instances, legislators suggest that the word "carries" has a broader scope. One legislator indicates that the statute responds in part to the concerns of law enforcement personnel, who had urged that "carrying short firearms in motor vehicles be classified as carrying such weapons concealed." Id., at 22242 (Rep. May). Another criticizes a version of the proposed statute by suggesting it might apply to drunken driving, and gives as an example a [134] drunken driver who has a "gun in his car." Id., at 21792 (Rep. Yates). Others describe the statute as criminalizing gun "possession"—a term that could stretch beyond both the "use" of a gun and the carrying of a gun on the person. See id., at 21793 (Rep. Casey); id., at 22236 (Rep. Meskill); id., at 30584 (Rep. Collier); id., at 30585 (Rep. Skubitz).

C

We are not convinced by petitioners' remaining arguments to the contrary. First, they say that our definition of "carry" makes it the equivalent of "transport." Yet, Congress elsewhere in related statutes used the word "transport" deliberately to signify a different, and broader, statutory coverage. The immediately preceding statutory subsection, for example, imposes a different set of penalties on one who, with an intent to commit a crime, "ships, transports, or receives a firearm" in interstate commerce. 18 U. S. C. § 924(b). Moreover, § 926A specifically "entitle[s]" a person "not otherwise prohibited . . . from transporting, shipping, or receiving a firearm" to "transport a firearm . . . from any place where he may lawfully possess and carry" it to "any other place" where he may do so. Why, petitioners ask, would Congress have used the word "transport," or used both "carry" and "transport" in the same provision, if it had intended to obliterate the distinction between the two?

The short answer is that our definition does not equate "carry" and "transport." "Carry" implies personal agency and some degree of possession, whereas "transport" does not have such a limited connotation and, in addition, implies the movement of goods in bulk over great distances. See Webster's Third New International Dictionary, at 343 (noting that "carry" means "moving to a location some distance away while supporting or maintaining off the ground" and "is a natural word to use in ref. to cargoes and loads on trucks, wagons, planes, ships, or even beasts of burden," while "transport refers to carriage in bulk or number over an appreciable [135] distance and, typically, by a customary or usual carrier agency"); see also Webster's Dictionary of Synonyms 141 (1942). If Smith, for example, calls a parcel delivery service, which sends a truck to Smith's house to pick up Smith's package and take it to Los Angeles, one might say that Smith has shipped the package and the parcel delivery service has transported the package. But only the truck driver has "carried" the package in the sense of "carry" that we believe Congress intended. Therefore, "transport" is a broader category that includes "carry" but also encompasses other activity.

The dissent refers to § 926A and to another statute where Congress used the word "transport" rather than "carry" to describe the movement of firearms. 18 U. S. C. § 925(a) (2)(B); post, at 146-147. According to the dissent, had Congress intended "carry" to have the meaning we give it, Congress would not have needed to use a different word in these provisions. But as we have discussed above, we believe the word "transport" is broader than the word "carry."

And, if Congress intended "carry" to have the limited definition the dissent contends, it would have been quite unnecessary to add the proviso in § 926A requiring a person, to be exempt from penalties, to store her firearm in a locked container not immediately accessible. See § 926A (quoted in full, post, at 146) (exempting from criminal penalties one who transports a firearm from a place where "he may lawfully possess and carry such firearm" but not exempting the "transportation" of a firearm if it is "readily accessible or is directly accessible from the passenger compartment of such transporting vehicle"). The statute simply could have said that such a person may not "carry" a firearm. But, of course, Congress did not say this because that is not what "carry" means.

As we interpret the statutory scheme, it makes sense. Congress has imposed a variable penalty with no mandatory minimum sentence upon a person who "transports" (or [136] "ships" or "receives") a firearm knowing it will be used to commit any "offense punishable by imprisonment for [more than] one year," § 924(b), and it has imposed a 5-year mandatory minimum sentence upon one who "carries" a firearm "during and in relation to" a "drug trafficking crime," § 924(c). The first subsection imposes a less strict sentencing regime upon one who, say, ships firearms by mail for use in a crime elsewhere; the latter subsection imposes a mandatory sentence upon one who, say, brings a weapon with him (on his person or in his car) to the site of a drug sale.

Second, petitioners point out that, in Bailey v. United States, 516 U. S. 137 (1995), we considered the related phrase "uses . . . a firearm" found in the same statutory provision now before us. See 18 U. S. C. § 924(c)(1) ("uses or carries a firearm"). We construed the term "use" narrowly, limiting its application to the "active employment" of a firearm. Bailey, 516 U. S., at 144. Petitioners argue that it would be anomalous to construe broadly the word "carries," its statutory next-door neighbor.

In Bailey, however, we limited "use" of a firearm to "active employment" in part because we assumed "that Congress. . . intended each term to have a particular, nonsuperfluous meaning." Id. , at 146. A broader interpretation of "use," we said, would have swallowed up the term "carry." Ibid. But "carry" as we interpret that word does not swallow up the term "use." "Use" retains the same independent meaning we found for it in Bailey, where we provided examples involving the displaying or the bartering of a gun. Ibid. "Carry" also retains an independent meaning, for, under Bailey, carrying a gun in a car does not necessarily involve the gun's "active employment." More importantly, having construed "use" narrowly in Bailey, we cannot also construe "carry" narrowly without undercutting the statute's basic objective. For the narrow interpretation would remove the act of carrying a gun in a car entirely from the statute's [137] reach, leaving a gap in coverage that we do not believe Congress intended.

Third, petitioners say that our reading of the statute would extend its coverage to passengers on buses, trains, or ships, who have placed a firearm, say, in checked luggage. To extend this statute so far, they argue, is unfair, going well beyond what Congress likely would have thought possible. They add that some lower courts, thinking approximately the same, have limited the scope of "carries" to instances where a gun in a car is immediately accessible, thereby most likely excluding from coverage a gun carried in a car's trunk or locked glove compartment. See, e. g. , Foster, 133 F. 3d, at 708 (concluding that person "carries" a firearm in a car only if the firearm is immediately accessible); Giraldo, 80 F. 3d, at 676 (same).

In our view, this argument does not take adequate account of other limiting words in the statute—words that make the statute applicable only where a defendant "carries" a gun both "during and in relation to" a drug crime. § 924(c)(1) (emphasis added). Congress added these words in part to prevent prosecution where guns "played" no part in the crime. See S. Rep. No. 98-225, at 314, n. 10; cf. United States v. Stewart, 779 F. 2d 538, 539 (CA9 1985) (Kennedy, J.) (observing that "`in relation to' " was "added to allay explicitly the concern that a person could be prosecuted . . . for committing an entirely unrelated crime while in possession of a firearm"), overruled in part on other grounds, United States v. Hernandez, 80 F. 3d 1253, 1257 (CA9 1996).

Once one takes account of the words "during" and "in relation to," it no longer seems beyond Congress' likely intent, or otherwise unfair, to interpret the statute as we have done. If one carries a gun in a car "during" and "in relation to" a drug sale, for example, the fact that the gun is carried in the car's trunk or locked glove compartment seems not only logically difficult to distinguish from the immediately accessible gun, but also beside the point.

[138] At the same time, the narrow interpretation creates its own anomalies. The statute, for example, defines "firearm" to include a "bomb," "grenade," "rocket having a propellant charge of more than four ounces," or "missile having an explosive or incendiary charge of more than one-quarter ounce," where such device is "explosive," "incendiary," or delivers "poison gas." 18 U. S. C. § 921(a)(4)(A). On petitioners' reading, the "carry" provision would not apply to instances where drug lords, engaged in a major transaction, took with them "firearms" such as these, which most likely could not be carried on the person.

Fourth, petitioners argue that we should construe the word "carry" to mean "immediately accessible." And, as we have said, they point out that several Courts of Appeals have limited the statute's scope in this way. See, e. g. , Foster, supra, at 708; Giraldo, supra, at 676. That interpretation, however, is difficult to square with the statute's language, for one "carries" a gun in the glove compartment whether or not that glove compartment is locked. Nothing in the statute's history suggests that Congress intended that limitation. And, for reasons pointed out above, see supra, at 137, we believe that the words "during" and "in relation to" will limit the statute's application to the harms that Congress foresaw.

Finally, petitioners and the dissent invoke the "rule of lenity." The simple existence of some statutory ambiguity, however, is not sufficient to warrant application of that rule, for most statutes are ambiguous to some degree. Cf. Smith, 508 U. S., at 239 ("The mere possibility of articulating a narrower construction . . . does not by itself make the rule of lenity applicable"). "`The rule of lenity applies only if, "after seizing everything from which aid can be derived," . . . we can make "no more than a guess as to what Congress intended."` " United States v. Wells, 519 U. S. 482, 499 (1997) (quoting Reno v. Koray, 515 U. S. 50, 65 (1995), in turn quoting Smith, supra, at 239, and Ladner v. United States, 358 U. S. 169, 178 (1958)). To invoke the rule, we must conclude [139] that there is a "` "grievous ambiguity or uncertainty"` in the statute." Staples v. United States, 511 U. S. 600, 619, n. 17 (1994) (quoting Chapman v. United States, 500 U. S. 453, 463 (1991)). Certainly, our decision today is based on much more than a "guess as to what Congress intended," and there is no "grievous ambiguity" here. The problem of statutory interpretation in these cases is indeed no different from that in many of the criminal cases that confront us. Yet, this Court has never held that the rule of lenity automatically permits a defendant to win.

In sum, the "generally accepted contemporary meaning" of the word "carry" includes the carrying of a firearm in a vehicle. The purpose of this statute warrants its application in such circumstances. The limiting phrase "during and in relation to" should prevent misuse of the statute to penalize those whose conduct does not create the risks of harm at which the statute aims.

For these reasons, we conclude that petitioners' conduct falls within the scope of the phrase "carries a firearm." The judgments of the Courts of Appeals are affirmed.

It is so ordered.

Justice Ginsburg, with whom The Chief Justice, Justice Scalia, and Justice Souter join, dissenting.

Section 924(c)(1) of Title 18, United States Code, is a punishment-enhancing provision; it imposes a mandatory five-year prison term when the defendant "during and in relation to any crime of violence or drug trafficking .. . uses or carries a firearm." In Bailey v. United States, 516 U. S. 137 (1995), this Court held that the term "uses," in the context of § 924(c)(1), means "active employment" of the firearm. In today's cases we confront a related question: What does the term "carries" mean in the context of § 924(c)(1), the enhanced punishment prescription again at issue.

It is uncontested that § 924(c)(1) applies when the defendant bears a firearm, i. e., carries the weapon on or about his [140] person "for the purpose of being armed and ready for offensive or defensive action in case of a conflict." Black's Law Dictionary 214 (6th ed. 1990) (defining the phrase "carry arms or weapons"); see ante, at 130. The Court holds that, in addition, "carries a firearm," in the context of § 924(c)(1), means personally transporting, possessing, or keeping a firearm in a vehicle, anyplace in a vehicle.

Without doubt, "carries" is a word of many meanings, definable to mean or include carting about in a vehicle. But that encompassing definition is not a ubiquitously necessary one. Nor, in my judgment, is it a proper construction of "carries" as the term appears in § 924(c)(1). In line with Bailey and the principle of lenity the Court has long followed, I would confine "carries a firearm," for § 924(c)(1) purposes, to the undoubted meaning of that expression in the relevant context. I would read the words to indicate not merely keeping arms on one's premises or in one's vehicle, but bearing them in such manner as to be ready for use as a weapon.

I

A

I note first what is at stake for petitioners. The question before the Court "is not whether possession of a gun [on the drug offender's premises or in his car, during and in relation to commission of the offense,] means a longer sentence for a convicted drug dealer. It most certainly does. . . . Rather, the question concerns which sentencing statute governs the precise length of the extra term of punishment," § 924(c)(1)'s "blunt `mandatory minimum' " five-year sentence, or the more finely tuned "sentencing guideline statutes, under which extra punishment for drug-related gun possession varies with the seriousness of the drug crime." United States v. McFadden, 13 F. 3d 463, 466 (CA1 1994) (Breyer, C. J., dissenting).

Accordingly, there would be no "gap," see ante, at 137, no relevant conduct "ignore[d]," see ante, at 133, were the Court to reject the Government's broad reading of § 924(c)(1). To [141] be more specific, as cogently explained on another day by today's opinion writer:

"The special `mandatory minimum' sentencing statute says that anyone who `uses or carries' a gun `during and in relation to any . . . drug trafficking crime' must receive a mandatory five-year prison term added on to his drug crime sentence. 18 U. S. C. § 924(c). At the same time, the Sentencing Guidelines, promulgated under the authority of a different statute, 28 U. S. C. § 994, provide for a two-level (i. e., a 30% to 40%) sentence enhancement where a `firearm . . . was possessed' by a drug offender, U. S. S. G. § 2D1.1(b)(1), unless the possession clearly was not `connected with the [drug] offense.' " McFadden, 13 F. 3d, at 467 (Breyer, C. J., dissenting).

In Muscarello's case, for example, the underlying drug crimes involved the distribution of 3.6 kilograms of marijuana, and therefore carried a base offense level of 12. See United States Sentencing Commission, Guidelines Manual § 2D1.1(a)(3) (Nov. 1995). After adjusting for Muscarello's acceptance of responsibility, see id., § 3E1.1(a), his final offense level was 10, placing him in the 6-to-12 month sentencing range. See id., ch. 5, pt. A. The two-level enhancement for possessing a firearm, id., § 2D1.1(b)(1), would have increased his final offense level to 12 (a sentencing range of 10 to 16 months). In other words, the less rigid (tailored to "the seriousness of the drug crime," McFadden, 13 F. 3d, at 466) Guidelines regime would have added four months to Muscarello's prison time, in contrast to the five-year minimum addition the Court's reading of § 924(c)(1) mandates.^[3]

[142] In sum, drug traffickers will receive significantly longer sentences if they are caught traveling in vehicles in which they have placed firearms. The question that divides the Court concerns the proper reference for enhancement in the cases at hand, the Guidelines or § 924(c)(1).

B

Unlike the Court, I do not think dictionaries,^[4] surveys of press reports,^[5] or the Bible^[6] tell us, dispositively, what "carries" [143] means embedded in § 924(c)(1). On definitions, "carry" in legal formulations could mean, inter alia, transport, possess, have in stock, prolong (carry over), be infectious, or wear or bear on one's person.^[7] At issue here is not "carries" at large but "carries a firearm." The Court's computer search of newspapers is revealing in this light. Carrying guns in a car showed up as the meaning "perhaps more than one-third" of the time. Ante, at 129. One is left to wonder what meaning showed up some two-thirds of the time. Surely a most familiar meaning is, as the Constitution's Second Amendment ("keep and bear Arms") (emphasis added) and Black's Law Dictionary, at 214, indicate: "wear, bear, or carry . . .upon the person or in the clothing or in a pocket, for the purpose .. . of being armed and ready for offensive or defensive action in a case of conflict with another person."

On lessons from literature, a scan of Bartlett's and other quotation collections shows how highly selective the Court's choices are. See ante, at 129. If "[t]he greatest of writers" have used "carry" to mean convey or transport in a vehicle, so have they used the hydra-headed word to mean, inter alia, carry in one's hand, arms, head, heart, or soul, sans vehicle. Consider, among countless examples:

"[H]e shall gather the lambs with his arm, and carry them in his bosom." The King James Bible, Isaiah 40:11.

"And still they gaz'd, and still the wonder grew,

[144] That one small head could carry all he knew." O. Goldsmith, The Deserted Village, ll. 215-216, in The Poetical Works of Oliver Goldsmith 30 (A. Dobson ed. 1949).

"There's a Legion that never was `listed, That carries no colours or crest." R. Kipling, The Lost Legion, st. 1, in Rudyard Kipling's Verse, 1885-1918, p. 222 (1920).

"There is a homely adage which runs, `Speak softly and carry a big stick; you will go far.' " T. Roosevelt, Speech at Minnesota State Fair, Sept. 2, 1901, in J. Bartlett, Familiar Quotations 575:16 (J. Kaplan ed. 1992).^[8]

These and the Court's lexicological sources demonstrate vividly that "carry" is a word commonly used to convey various messages. Such references, given their variety, are not reliable indicators of what Congress meant, in § 924(c)(1), by "carries a firearm."

C

Noting the paradoxical statement, "`I use a gun to protect my house, but I've never had to use it,' " the Court in Bailey, 516 U. S., at 143, emphasized the importance of context— the statutory context. Just as "uses" was read to mean not simply "possession," but "active employment," so "carries," correspondingly, is properly read to signal the most dangerous [145] cases—the gun at hand, ready for use as a weapon.^[9] It is reasonable to comprehend Congress as having provided mandatory minimums for the most life-jeopardizing gunconnection cases (guns in or at the defendant's hand when committing an offense), leaving other, less imminently threatening, situations for the more flexible Guidelines regime.^[10] As the Ninth Circuit suggested, it is not apparent why possession of a gun in a drug dealer's moving vehicle would be thought more dangerous than gun possession on premises where drugs are sold: "A drug dealer who packs heat is more likely to hurt someone or provoke someone else to violence. A gun in a bag under a tarp in a truck bed [or in a bedroom closet] poses substantially less risk." United States v. Foster, 133 F. 3d 704, 707 (1998) (en banc).^[11]

For indicators from Congress itself, it is appropriate to consider word usage in other provisions of Title 18's chapter on "Firearms." See Bailey, 516 U. S., at 143, 146 (interpreting § 924(c)(1) in light of 18 U. S. C. §§ 922(g), 922(j), 922(k), 922(o )(1), 924(d)(1), 930(a), 930(b)). The Court, however, [146] does not derive from the statutory complex at issue its thesis that "`[c]arry' implies personal agency and some degree of possession, whereas `transport' does not have such a limited connotation and, in addition, implies the movement of goods in bulk over great distances." Ante, at 134. Looking to provisions Congress enacted, one finds that the Legislature did not acknowledge or routinely adhere to the distinction the Court advances today; instead, Congress sometimes employed "transports" when, according to the Court, "carries" was the right word to use.

Section 925(a)(2)(B), for example, provides that no criminal sanction shall attend "the transportation of [a] firearm or ammunition carried out to enable a person, who lawfully received such firearm or ammunition from the Secretary of the Army, to engage in military training or in competitions." The full text of § 926A, rather than the truncated version the Court presents, see ibid., is also telling:

"Notwithstanding any other provision of any law or any rule or regulation of a State or any political subdivision thereof, any person who is not otherwise prohibited by this chapter from transporting, shipping, or receiving a firearm shall be entitled to transport a firearm for any lawful purpose from any place where he may lawfully possess and carry such firearm to any other place where he may lawfully possess and carry such firearm if, during such transportation the firearm is unloaded, and neither the firearm nor any ammunition being transported is readily accessible or is directly accessible from the passenger compartment of such transporting vehicle: Provided, That in the case of a vehicle without a compartment separate from the driver's compartment the firearm or ammunition shall be contained in a locked container other than the glove compartment or console."

In describing when and how a person may travel in a vehicle that contains his firearm without violating the law, [147] §§ 925(a)(2)(B) and 926A use "transport," not "carry," to "impl[y] personal agency and some degree of possession." Ibid.^[12]

Reading "carries" in § 924(c)(1) to mean "on or about [one's] person" is fully compatible with these and other "Firearms" statutes.^[13] For example, under § 925(a)(2)(B), one could carry his gun to a car, transport it to the shooting competition, and use it to shoot targets. Under the conditions of § 926A, one could transport her gun in a car, but under no circumstances could the gun be readily accessible while she travels in the car. "[C]ourts normally try to read language in different, but related, statutes, so as best to reconcile [148] those statutes, in light of their purposes and of common sense." McFadden, 13 F. 3d, at 467 (Breyer, C. J., dissenting). So reading the "Firearms" statutes, I would not extend the word "carries" in § 924(c)(1) to mean transports out of hand's reach in a vehicle.^[14]

II

Section 924(c)(1), as the foregoing discussion details, is not decisively clear one way or another. The sharp division in the Court on the proper reading of the measure confirms, "[a]t the very least, . . . that the issue is subject to some doubt. Under these circumstances, we adhere to the familiar rule that, `where there is ambiguity in a criminal statute, doubts are resolved in favor of the defendant.' " Adamo Wrecking Co. v. United States, 434 U. S. 275, 284-285 (1978) (citation omitted); see United States v. Granderson, 511 U. S. 39, 54 (1994) ("[W]here text, structure, and history fail to establish that the Government's position is unambiguously correct—we apply the rule of lenity and resolve the ambiguity in [the defendant's] favor."). "Carry" bears many meanings, [149] as the Court and the "Firearms" statutes demonstrate.^[15] The narrower "on or about [one's] person" interpretation is hardly implausible nor at odds with an accepted meaning of "carries a firearm."

Overlooking that there will be an enhanced sentence for the gun-possessing drug dealer in any event, see supra, at 140-142, the Court asks rhetorically: "How persuasive is a punishment that is without effect until a drug dealer who has brought his gun to a sale (indeed has it available for use) actually takes it from the trunk (or unlocks the glove compartment) of his car?" Ante, at 133. Correspondingly, the Court defines "carries a firearm" to cover "a person who knowingly possesses and conveys firearms [anyplace] in a vehicle . . . which the person accompanies." Ante, at 126-127. Congress, however, hardly lacks competence to select the words "possesses" or "conveys" when that is what the Legislature means.^[16] Notably in view of the Legislature's capacity to speak plainly, and of overriding concern, the Court's inquiry [150] pays scant attention to a core reason for the rule of lenity: "[B]ecause of the seriousness of criminal penalties, and because criminal punishment usually represents the moral condemnation of the community, legislatures and not courts should define criminal activity. This policy embodies `the instinctive distaste against men languishing in prison unless the lawmaker has clearly said they should.' " United States v. Bass, 404 U. S. 336, 348 (1971) (quoting H. Friendly, Mr. Justice Frankfurter and the Reading of Statutes, in Benchmarks 196, 209 (1967)).

* * *

The narrower "on or about [one's] person" construction of "carries a firearm" is consistent with the Court's construction of "uses" in Bailey to entail an immediacy element. It respects the Guidelines system by resisting overbroad readings of statutes that deviate from that system. See McFadden, 13 F. 3d, at 468 (Breyer, C. J., dissenting). It fits plausibly with other provisions of the "Firearms" chapter, and it adheres to the principle that, given two readings of a penal provision, both consistent with the statutory text, we do not choose the harsher construction. The Court, in my view, should leave it to Congress to speak "`in language that is clear and definite' " if the Legislature wishes to impose the sterner penalty. Bass, 404 U. S., at 347 (quoting United States v. Universal C. I. T. Credit Corp., 344 U. S. 218, 222 (1952)). Accordingly, I would reverse the judgments of the First and Fifth Circuits.

[1] Together with No. 96-8837, Cleveland et al. v. United States, on certiorari to the United States Court of Appeals for the First Circuit.

[2] Daniel Kanstroom, David Porter, and Kyle O'Dowd filed a brief for the National Association of Criminal Defense Lawyers et al. as amici curiae urging reversal.

[3] The Sentencing Guidelines carry out "a major congressional effort to create a fairly sophisticated . . . system that distinguishes among different kinds of criminal behavior and punishes accordingly." United States v. McFadden, 13 F. 3d, at 467-468 (Breyer, C. J., dissenting). A "mandatory minimum" statute deviates from the general regime Congress installed. "Given the importance (to Congress) of the Guidelines system, . . . courts should take care not to interpret [with unnecessary breadth] . . . deviations from the basic congressionally-directed effort to rationalize sentencing." Id., at 468.

[4] I note, however, that the only legal dictionary the Court cites, Black's Law Dictionary, defines "carry arms or weapons" restrictively. See ante, at 130; supra, at 139-140.

[5] Many newspapers, the New York Times among them, have published stories using "transport," rather than "carry," to describe gun placements resembling petitioners'. See, e. g., Atlanta Constitution, Feb. 27, 1998, p. 9D, col. 2 ("House members last week expanded gun laws by allowing weapons to be carried into restaurants or transported anywhere in cars. "); Chicago Tribune, June 12, 1997, sports section, p. 13 ("Disabled hunters with permission to hunt from a standing vehicle would be able to transport a shotgun in an all-terrain vehicle as long as the gun is unloaded and the breech is open."); Colorado Springs Gazette Telegraph, Aug. 4, 1996, p. C10 (British gun laws require "locked steel cases bolted onto a car for transporting guns from home to shooting range. "); Detroit News, Oct. 26, 1997, p. D14 ("It is unlawful to carry afield or transport a rifle . . . or shotgun if you have buckshot, slug, ball loads, or cut shells in possession except while traveling directly to deer camp or target range with firearm not readily available to vehicle occupants."); N. Y. Times, July 4, 1993, p. A21, col. 2 ("[T]he gun is supposed to be transported unloaded, in a locked box in the trunk."); Santa Rosa Press Democrat, Sept. 28, 1996, p. B1 ("Police and volunteers ask that participants . . . transport [their guns] to the fairgrounds in the trunks of their cars."); Worcester Telegram & Gazette, July 16, 1996, p. B3 ("Only one gun can be turned in per person. Guns transported in a vehicle should be locked in the trunk.") (emphasis added in all quotations).

[6] The translator of the Good Book, it appears, bore responsibility for determining whether the servants of Ahaziah "carried" his corpse to Jerusalem. Compare ante, at 129, with, e. g., The New English Bible, 2 Kings 9:28 ("His servants conveyed his body to Jerusalem."); Saint Joseph Edition of the New American Bible ("His servants brought him in a chariot to Jerusalem."); Tanakh: The Holy Scriptures ("His servants conveyed him in a chariot to Jerusalem."); see also id., Isaiah 30:6 ("They convey their wealth on the backs of asses."); The New Jerusalem Bible ("[T]hey bear their riches on donkeys' backs.") (emphasis added in all quotations).

[7] The dictionary to which this Court referred in Bailey v. United States, 516 U. S. 137, 145 (1995), contains 32 discrete definitions of "carry," including "[t]o make good or valid," "to bear the aspect of," and even "[t]o bear (a hawk) on the fist." See Webster's New International Dictionary 412 (2d ed. 1949).

[8] Popular films and television productions provide corroborative illustrations. In "The Magnificent Seven," for example, O'Reilly (played by Charles Bronson) says: "You think I am brave because I carry a gun; well, your fathers are much braver because they carry responsibility, for you, your brothers, your sisters, and your mothers." See http://us.imdb.com/ M/search_quotes?for=carry. And in the television series "M*A*S*H," Hawkeye Pierce (played by Alan Alda) presciently proclaims: "I will not carry a gun. .. .I'llcarry your books, I'llcarry a torch, I'llcarry a tune, I'll carry on, carry over, carry forward, Cary Grant, cash and carry, carry me back to Old Virginia, I'lleven `hari-kari' if you show me how, but I will not carry a gun!" See http://www.geocities.com/Hollywood/8915/ mashquotes.html.

[9] In my view, the Government would carry its burden by proving a firearm was kept so close to the person as to approximate placement in a pocket or holster, e. g., guns carried at one's side in a briefcase or handbag, or strapped to the saddle of a horse. See ante, at 130.

[10] The Court reports that the Courts of Appeals "have unanimously concluded that `carry' is not limited to the carrying of weapons directly on the person." Ante, at 131. In Bailey, however, the Government's argument based on a similar observation did not carry the day. See Brief for United States in Bailey v. United States, O. T. 1995, Nos. 94-7448 and 94-7492, p. 16, n. 4. No Court of Appeals had previously adopted an "active employment" construction of "uses . . . a firearm" in § 924(c)(1), yet this Court did exactly that. See 516 U. S., at 144.

[11] The "Firearms" statutes indicate that Congress, unlike the Court, ante, at 132-133, recognizes that a gun in the hand is indeed more dangerous than a gun in the trunk. See, e. g., 18 U. S. C. § 926A (permitting the transportation of firearms in a vehicle, but only if "neither the firearm nor any ammunition being transported is readily accessible or is directly accessible from the passenger compartment of such transporting vehicle"); see infra, at 146-147.

[12] The Court asserts that "`transport' is a broader category that includes `carry' but also encompasses other activity." Ante, at 135. "Carry," however, is not merely a subset of "transport." A person seated at a desk with a gun in hand or pocket is carrying the gun, but is not transporting it. Yes, the words "carry" and "transport" often can be employed interchangeably, as can the words "carry" and "use." But in Bailey, this Court settled on constructions that gave "carry" and "use" independent meanings. See 516 U. S., at 145-146. Without doubt, Congress is alert to the discrete meanings of "transport" and "carry" in the context of vehicles, as the Legislature's placement of each word in § 926A illustrates. The narrower reading of "carry" preserves discrete meanings for the two words, while in the context of vehicles the Court's interpretation of "carry" is altogether synonymous with "transport." Tellingly, when referring to firearms traveling in vehicles, the "Firearms" statutes routinely use a form of "transport"; they never use a form of "carry."

[13] See infra, at 149, nn. 13, 14. The Government points to numerous federal statutes that authorize law enforcement officers to "carry firearms" and notes that, in those authorizing provisions, "carry" of course means "both on the person and in a vehicle." Brief for United States 31-32, and n. 18. Quite right. But as viewers of "Sesame Street" will quickly recognize, "one of these things [a statute authorizing conduct] is not like the other [a statute criminalizing conduct]." The authorizing statutes in question are properly accorded a construction compatible with the clear purpose of the legislation to aid federal law enforcers in the performance of their official duties. It is fundamental, however, that a penal statute is not to be construed generously in the Government's favor. See, e. g., United States v. Bass, 404 U. S. 336, 348 (1971).

[14] The Court places undue reliance on Representative Poff's statement that § 924(c)(1) seeks "`to persuade the man who is tempted to commit a Federal felony to leave his gun at home.' " Ante, at 132 (quoting 114 Cong. Rec. 22231 (1968)). As the Government argued in its brief to this Court in Bailey: "In making that statement, Representative Poff was not referring to the `carries' prong of the original Section 924(c). As originally enacted, the `carries' prong of the statute prohibited only the `unlawful' carrying of a firearm while committing an offense. The statute would thus not have applied to an individual who, for instance, had a permit for carrying a gun and carried it with him when committing an offense, and it would have had no force in `persuading' such an individual `to leave his gun at home.' Instead, Representative Poff was referring to the `uses' prong of the original Section 924(c)." Brief for United States in Bailey v. United States, O. T. 1995, Nos. 94-7448 and 94-7492, p. 28. Representative Poff's next sentence confirms that he was speaking of "uses," not "carries": "Any person should understand that if he uses his gun and is caught and convicted, he is going to jail." 114 Cong. Rec., at 22231 (emphasis added).

[15] Any doubt on that score is dispelled by examining the provisions in the "Firearms" chapter, in addition to § 924(c)(1), that include a form of the word "carry": 18 U. S. C. § 922(a)(5) ("carry out a bequest"); §§ 922(s)(6)(B)(ii), (iii) ("carry out this subsection"); § 922(u) ("carry away [a firearm]"); 18 U. S. C. § 924(a)(6)(B)(ii) (1994 ed., Supp. II) ("carry or otherwise possess or discharge or otherwise use [a] handgun"); 18 U. S. C. § 924(e)(2)(B) ("carrying of a firearm"); § 925(a)(2) ("carried out to enable a person"); § 926(a) ("carry out the provisions of this chapter"); § 926A ("lawfully possess and carry such firearm to any other place where he may lawfully possess and carry such firearm"); § 929(a)(1) ("uses or carries a firearm and is in possession of armor piercing ammunition"); § 930(d)(3) ("lawful carrying of firearms . . . in a Federal facility incident to hunting or other lawful purposes") (emphasis added in all quotations).

[16] See, e. g., 18 U. S. C. § 924(a)(6)(B)(ii) (1994 ed., Supp. II) ("if the person sold . . . a handgun . . . to a juvenile knowing . . . that the juvenile intended to carry or otherwise possess . . . the handgun . . . in the commission of a crime of violence"); 18 U. S. C. § 926A ("may lawfully possess and carry such firearm to any other place where he may lawfully possess and carry such firearm"); § 929(a)(1) ("uses or carries a firearm and is in possession of armor piercing ammunition"); § 2277 ("brings, carries, or possesses any dangerous weapon") (emphasis added in all quotations).

467 U.S. 837 (1984)

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT

[839] Deputy Solicitor General Bator argued the cause for petitioners in all cases. With him on the briefs for petitioner in No. 82-1591 were Solicitor General Lee, Acting Assistant Attorney General Habicht, Deputy Assistant Attorney General Walker, Mark I. Levy, Anne S. Almy, William F. Pedersen, and Charles S. Carter. Michael H. Salinsky and Kevin M. Fong filed briefs for petitioner in No. 82-1005. Robert A. Emmett, David Ferber, Stark Ritchie, Theodore L. Garrett, Patricia A. Barald, Louis E. Tosi, William L. Patberg, Charles F. Lettow, and Barton C. Green filed briefs for petitioners in No. 82-1247.

David D. Doniger argued the cause and filed a brief for respondents.^[2]

A brief of amici curiae urging affirmance was filed for the Commonwealth of Pennsylvania et al. by LeRoy S. Zimmerman, Attorney General of Pennsylvania, Thomas Y. Au, Duane Woodard, Attorney General of Colorado, Richard L. Griffith, Assistant Attorney General, Joseph I. Lieberman, Attorney General of Connecticut, Robert A. Whitehead, Jr., Assistant Attorney General, James S. Tierney, Attorney General of Maine, Robert Abrams, Attorney General of New York, Marcia J. Cleveland and Mary L. Lyndon, Assistant Attorneys General, Irwin I. Kimmelman, Attorney General of New Jersey, John J. Easton, Jr., Attorney General of Vermont, Merideth Wright, Assistant Attorney General, Bronson C. La Follette, Attorney General of Wisconsin, and Maryann Sumi, Assistant Attorney General.

James D. English, Mary-Win O'Brien, and Bernard Kleiman filed a brief for the United Steelworkers of America, AFL-CIO-CLC, as amicus curiae.

JUSTICE STEVENS delivered the opinion of the Court.

In the Clean Air Act Amendments of 1977, Pub. L. 95-95, 91 Stat. 685, Congress enacted certain requirements applicable [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.^[3] The EPA regulation promulgated to implement this permit requirement allows a State to adopt a plantwide definition of the term "stationary source."^[4] 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 [841] 14, 1981. 46 Fed. Reg. 50766. Respondents^[5] 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).^[6] 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.^[7] Based on two of its precedents concerning the applicability of the bubble concept to certain Clean Air Act programs,^[8] 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 [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.^[9] Nevertheless, since this Court reviews judgments, not opinions,^[10] 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, [843] as well as the agency, must give effect to the unambiguously expressed intent of Congress.^[11] 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,^[12] 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.^[13]

"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 [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.^[14] 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 provision for a reasonable interpretation made by the administrator of an agency.^[15]

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,^[16] 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. [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.

III

In the 1950's and the 1960's Congress enacted a series of statutes designed to encourage and to assist the States in curtailing air pollution. See generally Train v. Natural Resources Defense Council, Inc., 421 U. S. 60, 63-64 (1975). The Clean Air Amendments of 1970, Pub. L. 91-604, 84 Stat. 1976, "sharply increased federal authority and responsibility [846] in the continuing effort to combat air pollution," 421 U. S., at 64, but continued to assign "primary responsibility for assuring air quality" to the several States, 84 Stat. 1678. Section 109 of the 1970 Amendments directed the EPA to promulgate National Ambient Air Quality Standards (NAAQS's)^[17] and § 110 directed the States to develop plans (SIP's) to implement the standards within specified deadlines. In addition, § 111 provided that major new sources of pollution would be required to conform to technology-based performance standards; the EPA was directed to publish a list of categories of sources of pollution and to establish new source performance standards (NSPS) for each. Section 111(e) prohibited the operation of any new source in violation of a performance standard.

Section 111(a) defined the terms that are to be used in setting and enforcing standards of performance for new stationary sources. It provided:

"For purposes of this section:

.....

"(3) The term `stationary source' means any building, structure, facility, or installation which emits or may emit any air pollutant." 84 Stat. 1683.

In the 1970 Amendments that definition was not only applicable to the NSPS program required by § 111, but also was made applicable to a requirement of § 110 that each state implementation plan contain a procedure for reviewing the location of any proposed new source and preventing its construction if it would preclude the attainment or maintenance of national air quality standards.^[18]

In due course, the EPA promulgated NAAQS's, approved SIP's, and adopted detailed regulations governing NSPS's [847] for various categories of equipment. In one of its programs, the EPA used a plantwide definition of the term "stationary source." In 1974, it issued NSPS's for the nonferrous smelting industry that provided that the standards would not apply to the modification of major smelting units if their increased emissions were offset by reductions in other portions of the same plant.^[19]

Nonattainment

The 1970 legislation provided for the attainment of primary NAAQS's by 1975. In many areas of the country, particularly the most industrialized States, the statutory goals were not attained.^[20] In 1976, the 94th Congress was confronted with this fundamental problem, as well as many others respecting pollution control. As always in this area, the legislative struggle was basically between interests seeking strict schemes to reduce pollution rapidly to eliminate its social costs and interests advancing the economic concern that strict schemes would retard industrial development with attendant social costs. The 94th Congress, confronting these competing interests, was unable to agree on what response was in the public interest: legislative proposals to deal with nonattainment failed to command the necessary consensus.^[21]

In light of this situation, the EPA published an Emissions Offset Interpretive Ruling in December 1976, see 41 Fed. Reg. 55524, to "fill the gap," as respondents put it, until Congress acted. The Ruling stated that it was intended to [848] address "the issue of whether and to what extent national air quality standards established under the Clean Air Act may restrict or prohibit growth of major new or expanded stationary air pollution sources." Id., at 55524-55525. In general, the Ruling provided that "a major new source may locate in an area with air quality worse than a national standard only if stringent conditions can be met." Id., at 55525. The Ruling gave primary emphasis to the rapid attainment of the statute's environmental goals.^[22] Consistent with that emphasis, the construction of every new source in nonattainment areas had to meet the "lowest achievable emission rate" under the current state of the art for that type of facility. See Ibid. The 1976 Ruling did not, however, explicitly adopt or reject the "bubble concept."^[23]

IV

The Clean Air Act Amendments of 1977 are a lengthy, detailed, technical, complex, and comprehensive response to a major social issue. A small portion of the statute — 91 Stat. [849] 745-751 (Part D of Title I of the amended Act, 42 U. S. C. §§ 7501-7508) — expressly deals with nonattainment areas. The focal point of this controversy is one phrase in that portion of the Amendments.^[24]

Basically, the statute required each State in a nonattainment area to prepare and obtain approval of a new SIP by July 1, 1979. In the interim those States were required to comply with the EPA's interpretative Ruling of December 21, 1976. 91 Stat. 745. The deadline for attainment of the primary NAAQS's was extended until December 31, 1982, and in some cases until December 31, 1987, but the SIP's were required to contain a number of provisions designed to achieve the goals as expeditiously as possible.^[25]

[850] Most significantly for our purposes, the statute provided that each plan shall

"(6) require permits for the construction and operation of new or modified major stationary sources in accordance with section 173 . . . ." Id., at 747.

Before issuing a permit, § 173 requires (1) the state agency to determine that there will be sufficient emissions reductions in the region to offset the emissions from the new source and also to allow for reasonable further progress toward attainment, or that the increased emissions will not exceed an allowance for growth established pursuant to § 172(b)(5); (2) the applicant to certify that his other sources in the State are in compliance with the SIP, (3) the agency to determine that the applicable SIP is otherwise being implemented, and (4) the proposed source to comply with the lowest achievable emission rate (LAER).^[26]

[851] The 1977 Amendments contain no specific reference to the "bubble concept." Nor do they contain a specific definition of the term "stationary source," though they did not disturb the definition of "stationary source" contained in § 111(a)(3), applicable by the terms of the Act to the NSPS program. Section 302(j), however, defines the term "major stationary source" as follows:

"(j) Except as otherwise expressly provided, the terms `major stationary source' and `major emitting facility' mean any stationary facility or source of air pollutants which directly emits, or has the potential to emit, one hundred tons per year or more of any air pollutant (including any major emitting facility or source of fugitive emissions of any such pollutant, as determined by rule by the Administrator)." 91 Stat. 770.

V

The legislative history of the portion of the 1977 Amendments dealing with nonattainment areas does not contain any specific comment on the "bubble concept" or the question whether a plantwide definition of a stationary source is permissible under the permit program. It does, however, plainly disclose that in the permit program Congress sought to accommodate the conflict between the economic interest in permitting capital improvements to continue and the environmental interest in improving air quality. Indeed, the House Committee Report identified the economic interest as one of the "two main purposes" of this section of the bill. It stated:

"Section 117 of the bill, adopted during full committee markup establishes a new section 127 of the Clean Air Act. The section has two main purposes: (1) to allow reasonable economic growth to continue in an area while making reasonable further progress to assure attainment of the standards by a fixed date; and (2) to allow [852] States greater flexibility for the former purpose than EPA's present interpretative regulations afford.

"The new provision allows States with nonattainment areas to pursue one of two options. First, the State may proceed under EPA's present `tradeoff' or `offset' ruling. The Administrator is authorized, moreover, to modify or amend that ruling in accordance with the intent and purposes of this section.

"The State's second option would be to revise its implementation plan in accordance with this new provision." H. R. Rep. No. 95-294, p. 211 (1977).^[27]

The portion of the Senate Committee Report dealing with nonattainment areas states generally that it was intended to "supersede the EPA administrative approach," and that expansion should be permitted if a State could "demonstrate that these facilities can be accommodated within its overall plan to provide for attainment of air quality standards." S. Rep. No. 95-127, p. 55 (1977). The Senate Report notes the value of "case-by-case review of each new or modified major source of pollution that seeks to locate in a region exceeding an ambient standard," explaining that such a review "requires matching reductions from existing sources against [853] emissions expected from the new source in order to assure that introduction of the new source will not prevent attainment of the applicable standard by the statutory deadline." Ibid. This description of a case-by-case approach to plant additions, which emphasizes the net consequences of the construction or modification of a new source, as well as its impact on the overall achievement of the national standards, was not, however, addressed to the precise issue raised by these cases.

Senator Muskie made the following remarks:

"I should note that the test for determining whether a new or modified source is subject to the EPA interpretative regulation [the Offset Ruling] — and to the permit requirements of the revised implementation plans under the conference bill — is whether the source will emit a pollutant into an area which is exceeding a national ambient air quality standard for that pollutant — or precursor. Thus, a new source is still subject to such requirements as `lowest achievable emission rate' even if it is constructed as a replacement for an older facility resulting in a net reduction from previous emission levels.

"A source — including an existing facility ordered to convert to coal — is subject to all the nonattainment requirements as a modified source if it makes any physical change which increases the amount of any air pollutant for which the standards in the area are exceeded." 123 Cong. Rec. 26847 (1977).

VI

As previously noted, prior to the 1977 Amendments, the EPA had adhered to a plantwide definition of the term "source" under a NSPS program. After adoption of the 1977 Amendments, proposals for a plantwide definition were considered in at least three formal proceedings.

In January 1979, the EPA considered the question whether the same restriction on new construction in nonattainment areas that had been included in its December 1976 Ruling [854] should be required in the revised SIP's that were scheduled to go into effect in July 1979. After noting that the 1976 Ruling was ambiguous on the question "whether a plant with a number of different processes and emission points would be considered a single source," 44 Fed. Reg. 3276 (1979), the EPA, in effect, provided a bifurcated answer to that question. In those areas that did not have a revised SIP in effect by July 1979, the EPA rejected the plantwide definition; on the other hand, it expressly concluded that the plantwide approach would be permissible in certain circumstances if authorized by an approved SIP. It stated:

"Where a state implementation plan is revised and implemented to satisfy the requirements of Part D, including the reasonable further progress requirement, the plan requirements for major modifications may exempt modifications of existing facilities that are accompanied by intrasource offsets so that there is no net increase in emissions. The agency endorses such exemptions, which would provide greater flexibility to sources to effectively manage their air emissions at least cost." Ibid.^[28]

[855] In April, and again in September 1979, the EPA published additional comments in which it indicated that revised SIP's could adopt the plantwide definition of source in nonattainment areas in certain circumstances. See id., at 20372, 20379, 51924, 51951, 51958. On the latter occasion, the EPA made a formal rulemaking proposal that would have permitted the use of the "bubble concept" for new installations within a plant as well as for modifications of existing units. It explained:

" `Bubble' Exemption: The use of offsets inside the same source is called the `bubble.' EPA proposes use of the definition of `source' (see above) to limit the use of the bubble under nonattainment requirements in the following respects:

"i. Part D SIPs that include all requirements needed to assure reasonable further progress and attainment by the deadline under section 172 and that are being carried out need not restrict the use of a plantwide bubble, the same as under the PSD proposal.

"ii. Part D SIPs that do not meet the requirements specified must limit use of the bubble by including a definition of `installation' as an identifiable piece of process equipment."^[29]

[856] Significantly, the EPA expressly noted that the word "source" might be given a plantwide definition for some purposes and a narrower definition for other purposes. It wrote:

"Source means any building structure, facility, or installation which emits or may emit any regulated pollutant. `Building, structure, facility or installation' means plant in PSD areas and in nonattainment areas except where the growth prohibitions would apply or where no adequate SIP exists or is being carried out." Id., at 51925.^[30]

The EPA's summary of its proposed Ruling discloses a flexible rather than rigid definition of the term "source" to implement various policies and programs:

"In summary, EPA is proposing two different ways to define source for different kinds of NSR programs:

"(1) For PSD and complete Part D SIPs, review would apply only to plants, with an unrestricted plant-wide bubble.

"(2) For the offset ruling, restrictions on construction, and incomplete Part D SIPs, review would apply to both plants and individual pieces of process equipment, causing the plant-wide bubble not to apply for new and modified major pieces of equipment.

"In addition, for the restrictions on construction, EPA is proposing to define `major modification' so as to prohibit the bubble entirely. Finally, an alternative discussed but not favored is to have only pieces of process equipment reviewed, resulting in no plant-wide bubble and allowing minor pieces of equipment to escape NSR [857] regardless of whether they are within a major plant." Id., at 51934.

In August 1980, however, the EPA adopted a regulation that, in essence, applied the basic reasoning of the Court of Appeals in these cases. The EPA took particular note of the two then-recent Court of Appeals decisions, which had created the bright-line rule that the "bubble concept" should be employed in a program designed to maintain air quality but not in one designed to enhance air quality. Relying heavily on those cases,^[31] EPA adopted a dual definition of "source" for nonattainment areas that required a permit whenever a change in either the entire plant, or one of its components, would result in a significant increase in emissions even if the increase was completely offset by reductions elsewhere in the plant. The EPA expressed the opinion that this interpretation was "more consistent with congressional intent" than the plantwide definition because it "would bring in more sources or modifications for review," 45 Fed. Reg. 52697 (1980), but its primary legal analysis was predicated on the two Court of Appeals decisions.

In 1981 a new administration took office and initiated a "Government-wide reexamination of regulatory burdens and complexities." 46 Fed. Reg. 16281. In the context of that [858] review, the EPA reevaluated the various arguments that had been advanced in connection with the proper definition of the term "source" and concluded that the term should be given the same definition in both nonattainment areas and PSD areas.

In explaining its conclusion, the EPA first noted that the definitional issue was not squarely addressed in either the statute or its legislative history and therefore that the issue involved an agency "judgment as how to best carry out the Act." Ibid. It then set forth several reasons for concluding that the plantwide definition was more appropriate. It pointed out that the dual definition "can act as a disincentive to new investment and modernization by discouraging modifications to existing facilities" and "can actually retard progress in air pollution control by discouraging replacement of older, dirtier processes or pieces of equipment with new, cleaner ones." Ibid. Moreover, the new definition "would simplify EPA's rules by using the same definition of `source' for PSD, nonattainment new source review and the construction moratorium. This reduces confusion and inconsistency." Ibid. Finally, the agency explained that additional requirements that remained in place would accomplish the fundamental purposes of achieving attainment with NAAQS's as expeditiously as possible.^[32] These conclusions were expressed [859] in a proposed rulemaking in August 1981 that was formally promulgated in October. See id., at 50766.

VII

In this Court respondents expressly reject the basic rationable of the Court of Appeals' decision. That court viewed the statutory definition of the term "source" as sufficiently flexible to cover either a plantwide definition, a narrower definition covering each unit within a plant, or a dual definition that could apply to both the entire "bubble" and its components. It interpreted the policies of the statute, however, to mandate the plantwide definition in programs designed to maintain clean air and to forbid it in programs designed to improve air quality. Respondents place a fundamentally different construction on the statute. They contend that the text of the Act requires the EPA to use a dual definition — if either a component of a plant, or the plant as a whole, emits over 100 tons of pollutant, it is a major stationary source. They thus contend that the EPA rules adopted in 1980, insofar as they apply to the maintenance of the quality of clean air, as well as the 1981 rules which apply to nonattainment areas, violate the statute.^[33]

Statutory Language

The definition of the term "stationary source" in § 111(a)(3) refers to "any building, structure, facility, or installation" which emits air pollution. See supra, at 846. This definition is applicable only to the NSPS program by the express terms of the statute; the text of the statute does not make this definition [860] applicable to the permit program. Petitioners therefore maintain that there is no statutory language even relevant to ascertaining the meaning of stationary source in the permit program aside from § 302(j), which defines the term "major stationary source." See supra, at 851. We disagree with petitioners on this point.

The definition in § 302(j) tells us what the word "major" means — a source must emit at least 100 tons of pollution to qualify — but it sheds virtually no light on the meaning of the term "stationary source." It does equate a source with a facility — a "major emitting facility" and a "major stationary source" are synonymous under § 302(j). The ordinary meaning of the term "facility" is some collection of integrated elements which has been designed and constructed to achieve some purpose. Moreover, it is certainly no affront to common English usage to take a reference to a major facility or a major source to connote an entire plant as opposed to its constituent parts. Basically, however, the language of § 302(j) simply does not compel any given interpretation of the term "source."

Respondents recognize that, and hence point to § 111(a)(3). Although the definition in that section is not literally applicable to the permit program, it sheds as much light on the meaning of the word "source" as anything in the statute.^[34] As respondents point out, use of the words "building, structure, facility, or installation," as the definition of source, could be read to impose the permit conditions on an individual building that is a part of a plant.^[35] A "word may have a character of its own not to be submerged by its association." Russell Motor Car Co. v. United States, 261 U. S. 514, 519 [861] (1923). On the other hand, the meaning of a word must be ascertained in the context of achieving particular objectives, and the words associated with it may indicate that the true meaning of the series is to convey a common idea. The language may reasonably be interpreted to impose the requirement on any discrete, but integrated, operation which pollutes. This gives meaning to all of the terms — a single building, not part of a larger operation, would be covered if it emits more than 100 tons of pollution, as would any facility, structure, or installation. Indeed, the language itself implies a "bubble concept" of sorts: each enumerated item would seem to be treated as if it were encased in a bubble. While respondents insist that each of these terms must be given a discrete meaning, they also argue that § 111(a)(3) defines "source" as that term is used in § 302(j). The latter section, however, equates a source with a facility, whereas the former defines "source" as a facility, among other items.

We are not persuaded that parsing of general terms in the text of the statute will reveal an actual intent of Congress.^[36] [862] We know full well that this language is not dispositive; the terms are overlapping and the language is not precisely directed to the question of the applicability of a given term in the context of a larger operation. To the extent any congressional "intent" can be discerned from this language, it would appear that the listing of overlapping, illustrative terms was intended to enlarge, rather than to confine, the scope of the agency's power to regulate particular sources in order to effectuate the policies of the Act.

Legislative History

In addition, respondents argue that the legislative history and policies of the Act foreclose the plantwide definition, and that the EPA's interpretation is not entitled to deference because it represents a sharp break with prior interpretations of the Act.

Based on our examination of the legislative history, we agree with the Court of Appeals that it is unilluminating. The general remarks pointed to by respondents "were obviously not made with this narrow issue in mind and they cannot be said to demonstrate a Congressional desire . . . ." Jewell Ridge Coal Corp. v. Mine Workers, 325 U. S. 161, 168-169 (1945). Respondents' argument based on the legislative history relies heavily on Senator Muskie's observation that a new source is subject to the LAER requirement.^[37] But the full statement is ambiguous and like the text of § 173 itself, this comment does not tell us what a new source is, much less that it is to have an inflexible definition. We find that the legislative history as a whole is silent on the precise issue before us. It is, however, consistent with the view that the EPA should have broad discretion in implementing the policies of the 1977 Amendments.

[863] More importantly, that history plainly identifies the policy concerns that motivated the enactment; the plantwide definition is fully consistent with one of those concerns — the allowance of reasonable economic growth — and, whether or not we believe it most effectively implements the other, we must recognize that the EPA has advanced a reasonable explanation for its conclusion that the regulations serve the environmental objectives as well. See supra, at 857-859, and n. 29; see also supra, at 855, n. 27. Indeed, its reasoning is supported by the public record developed in the rulemaking process,^[38] as well as by certain private studies.^[39]

Our review of the EPA's varying interpretations of the word "source" — both before and after the 1977 Amendments — convinces us that the agency primarily responsible for administering this important legislation has consistently interpreted it flexibly — not in a sterile textual vacuum, but in the context of implementing policy decisions in a technical and complex arena. The fact that the agency has from time to time changed its interpretation of the term "source" does not, as respondents argue, lead us to conclude that no deference should be accorded the agency's interpretation of the statute. An initial agency interpretation is not instantly carved in stone. On the contrary, the agency, to engage in informed rulemaking, must consider varying interpretations [864] and the wisdom of its policy on a continuing basis. Moreover, the fact that the agency has adopted different definitions in different contexts adds force to the argument that the definition itself is flexible, particularly since Congress has never indicated any disapproval of a flexible reading of the statute.

Significantly, it was not the agency in 1980, but rather the Court of Appeals that read the statute inflexibly to command a plantwide definition for programs designed to maintain clean air and to forbid such a definition for programs designed to improve air quality. The distinction the court drew may well be a sensible one, but our labored review of the problem has surely disclosed that it is not a distinction that Congress ever articulated itself, or one that the EPA found in the statute before the courts began to review the legislative work product. We conclude that it was the Court of Appeals, rather than Congress or any of the decisionmakers who are authorized by Congress to administer this legislation, that was primarily responsible for the 1980 position taken by the agency.

Policy

The arguments over policy that are advanced in the parties' briefs create the impression that respondents are now waging in a judicial forum a specific policy battle which they ultimately lost in the agency and in the 32 jurisdictions opting for the "bubble concept," but one which was never waged in the Congress. Such policy arguments are more properly addressed to legislators or administrators, not to judges.^[40]

[865] In these cases the Administrator's interpretation represents a reasonable accommodation of manifestly competing interests and is entitled to deference: the regulatory scheme is technical and complex,^[41] the agency considered the matter in a detailed and reasoned fashion,^[42] and the decision involves reconciling conflicting policies.^[43] Congress intended to accommodate both interests, but did not do so itself on the level of specificity presented by these cases. Perhaps that body consciously desired the Administrator to strike the balance at this level, thinking that those with great expertise and charged with responsibility for administering the provision would be in a better position to do so; perhaps it simply did not consider the question at this level; and perhaps Congress was unable to forge a coalition on either side of the question, and those on each side decided to take their chances with the scheme devised by the agency. For judicial purposes, it matters not which of these things occurred.

Judges are not experts in the field, and are not part of either political branch of the Government. Courts must, in some cases, reconcile competing political interests, but not on the basis of the judges' personal policy preferences. In contrast, an agency to which Congress has delegated policymaking responsibilities may, within the limits of that delegation, properly rely upon the incumbent administration's views of wise policy to inform its judgments. While agencies are not directly accountable to the people, the Chief Executive is, and it is entirely appropriate for this political branch of the Government to make such policy choices — resolving the competing interests which Congress itself either inadvertently did not resolve, or intentionally left to be resolved by the [866] agency charged with the administration of the statute in light of everyday realities.

When a challenge to an agency construction of a statutory provision, fairly conceptualized, really centers on the wisdom of the agency's policy, rather than whether it is a reasonable choice within a gap left open by Congress, the challenge must fail. In such a case, federal judges — who have no constituency — have a duty to respect legitimate policy choices made by those who do. The responsibilities for assessing the wisdom of such policy choices and resolving the struggle between competing views of the public interest are not judicial ones: "Our Constitution vests such responsibilities in the political branches." TVA v. Hill, 437 U. S. 153, 195 (1978).

We hold that the EPA's definition of the term "source" is a permissible construction of the statute which seeks to accommodate progress in reducing air pollution with economic growth. "The Regulations which the Administrator has adopted provide what the agency could allowably view as . . . [an] effective reconciliation of these twofold ends . . . ." United States v. Shimer, 367 U. S., at 383.

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.

[1] Together with No. 82-1247, American Iron & Steel Institute et al. v. Natural Resources Defense Council, Inc., et al.; and No. 82-1591, Ruckelshaus, Administrator, Environmental Protection Agency v. Natural Resources Defense Council, Inc., et al., also on certiorari to the same court.

[2] Briefs of amici curiae urging reversal were filed for the American Gas Association by John A. Myler; for the Mid-America Legal Foundation by John M. Cannon, Susan W. Wanat, and Ann P. Sheldon; and for the Pacific Legal Foundation by Ronald A. Zumbrun and Robin L. Rivett.

[3] Section 172(b)(6), 42 U. S. C. § 7502(b)(6), provides:

"The plan provisions required by subsection (a) shall —

.....

"(6) require permits for the construction and operation of new or modified major stationary sources in accordance with section 173 (relating to permit requirements)." 91 Stat. 747.

[4] "(i) `Stationary source' means any building, structure, facility, or installation which emits or may emit any air pollutant subject to regulation under the Act.

"(ii) `Building, structure, facility, or installation' means all of the pollutant-emitting activities which belong to the same industrial grouping, are located on one or more contiguous or adjacent properties, and are under the control of the same person (or persons under common control) except the activities of any vessel." 40 CFR §§ 51.18(j)(1)(i) and (ii) (1983).

[5] National Resources Defense Council, Inc., Citizens for a Better Environment, Inc., and North Western Ohio Lung Association, Inc.

[6] Petitioners, Chevron U. S. A. Inc., American Iron and Steel Institute, American Petroleum Institute, Chemical Manufacturers Association, Inc., General Motors Corp., and Rubber Manufacturers Association were granted leave to intervene and argue in support of the regulation.

[7] The court remarked in this regard:

"We regret, of course, that Congress did not advert specifically to the bubble concept's application to various Clean Air Act programs, and note that a further clarifying statutory directive would facilitate the work of the agency and of the court in their endeavors to serve the legislators' will." 222 U. S. App. D. C., at 276, n. 39, 685 F. 2d, at 726, n. 39.

[8] Alabama Power Co. v. Costle, 204 U. S. App. D. C. 51, 636 F. 2d 323 (1979); ASARCO Inc. v. EPA, 188 U. S. App. D. C. 77, 578 F. 2d 319 (1978).

[9] Respondents argued below that EPA's plantwide definition of "stationary source" is contrary to the terms, legislative history, and purposes of the amended Clear Air Act. The court below rejected respondents' arguments based on the language and legislative history of the Act. It did agree with respondents contention that the regulations were inconsistent with the purposes of the Act, but did not adopt the construction of the statute advanced by respondents here. Respondents rely on the arguments rejected by the Court of Appeals in support of the judgment, and may rely on any ground that finds support in the record. See Ryerson v. United States, 312 U. S. 405, 408 (1941); LeTulle v. Scofield, 308 U. S. 415, 421 (1940); Langnes v. Green, 282 U. S. 531, 533-539 (1931).

[10] E. g., Black v. Cutter Laboratories, 351 U. S. 292, 297 (1956); J. E. Riley Investment Co. v. Commissioner, 311 U. S. 55, 59 (1940); Williams v. Norris, 12 Wheat. 117, 120 (1827); McClung v. Silliman, 6 Wheat. 598, 603 (1821).

[11] The judiciary is the final authority on issues of statutory construction and must reject administrative constructions which are contrary to clear congressional intent. See, e. g., FEC v. Democratic Senatorial Campaign Committee, 454 U. S. 27, 32 (1981); SEC v. Sloan, 436 U. S. 103, 117-118 (1978); FMC v. Seatrain Lines, Inc., 411 U. S. 726, 745-746 (1973); Volkswagenwerk v. FMC, 390 U. S. 261, 272 (1968); NLRB v. Brown, 380 U. S. 278, 291 (1965); FTC v. Colgate-Palmolive Co., 380 U. S. 374, 385 (1965); Social Security Board v. Nierotko, 327 U. S. 358, 369 (1946); Burnet v. Chicago Portrait Co., 285 U. S. 1, 16 (1932); Webster v. Luther, 163 U. S. 331, 342 (1896). If a court, employing traditional tools of statutory construction, ascertains that Congress had an intention on the precise question at issue, that intention is the law and must be given effect.

[12] See generally, R. Pound, The Spirit of the Common Law 174-175 (1921).

[13] The court need not conclude that the agency construction was the only one it permissibly could have adopted to uphold the construction, or even the reading the court would have reached if the question initially had arisen in a judicial proceeding. FEC v. Democratic Senatorial Campaign Committee, 454 U. S., at 39; Zenith Radio Corp. v. United States, 437 U. S. 443, 450 (1978); Train v. Natural Resources Defense Council, Inc., 421 U. S. 60, 75 (1975); Udall v. Tallman, 380 U. S. 1, 16 (1965); Unemployment Compensation Comm'n v. Aragon, 329 U. S. 143, 153 (1946); McLaren v. Fleischer, 256 U. S. 477, 480-481 (1921).

[14] See, e. g., United States v. Morton, ante, at 834; Schweiker v. Gray Panthers, 453 U. S. 34, 44 (1981); Batterton v. Francis, 432 U. S. 416, 424-426 (1977); American Telephone & Telegraph Co. v. United States, 299 U. S. 232, 235-237 (1936).

[15] E. g., INS v. Jong Ha Wang, 450 U. S. 139, 144 (1981); Train v. Natural Resources Defense Council, Inc., 421 U. S., at 87.

[16] Aluminum Co. of America v. Central Lincoln Peoples' Until Dist., ante, at 389; Blum v. Bacon, 457 U. S. 132, 141 (1982); Union Electric Co. v. EPA, 427 U. S. 246, 256 (1976); Investment Company Institute v. Camp, 401 U. S. 617, 626-627 (1971); Unemployment Compensation Comm'n v. Aragon, 329 U. S., at 153-154; NLRB v. Hearst Publications, Inc., 322 U. S. 111, 131 (1944); McLaren v. Fleischer, 256 U. S., at 480-481; Webster v. Luther, 163 U. S., at 342; Brown v. United States, 113 U. S. 568, 570-571 (1885); United States v. Moore, 95 U. S. 760, 763 (1878); Edwards' Lessee v. Darby, 12 Wheat. 206, 210 (1827).

[17] Primary standards were defined as those whose attainment and maintenance were necessary to protect the public health, and secondary standards were intended to specify a level of air quality that would protect the public welfare.

[18] See §§ 110(a)(2)(D) and 110(a)(4).

[19] The Court of Appeals ultimately held that this plantwide approach was prohibited by the 1970 Act, see ASARCO Inc., 188 U. S. App. D. C., at 83-84, 578 F. 2d, at 325-327. This decision was rendered after enactment of the 1977 Amendments, and hence the standard was in effect when Congress enacted the 1977 Amendments.

[20] See Report of the National Commission on Air Quality, To Breathe Clean Air, 3.3-20 through 3.3-33 (1981).

[21] Comprehensive bills did pass both Chambers of Congress; the Conference Report was rejected in the Senate. 122 Cong. Rec. 34375-34403, 34405-34418 (1976).

[22] For example, it stated:

"Particularly with regard to the primary NAAQS's, Congress and the Courts have made clear that economic considerations must be subordinated to NAAQS achievement and maintenance. While the ruling allows for some growth in areas violating a NAAQS if the net effect is to insure further progress toward NAAQS achievement, the Act does not allow economic growth to be accommodated at the expense of the public health." 41 Fed. Reg. 55527 (1976).

[23] In January 1979, the EPA noted that the 1976 Ruling was ambiguous concerning this issue:

"A number of commenters indicated the need for a more explicit definition of `source.' Some readers found that it was unclear under the 1976 Ruling whether a plant with a number of different processes and emission points would be considered a single source. The changes set forth below define a source as `any structure, building, facility, equipment, installation, or operation (or combination thereof) which is located on one or more contiguous or adjacent properties and which is owned or operated by the same person (or by persons under common control).' This definition precludes a large plant from being separated into individual production lines for purposes of determining applicability of the offset requirements." 44 Fed. Reg. 3276.

[24] Specifically, the controversy in these cases involves the meaning of the term "major stationary sources" in § 172(b)(6) of the Act, 42 U. S. C. § 7502(b)(6). The meaning of the term "proposed source" in § 173(2) of the Act, 42 U. S. C. § 7503(2), is not at issue.

[25] Thus, among other requirements, § 172(b) provided that the SIP's shall —

"(3) require, in the interim, reasonable further progress (as defined in section 171(1)) including such reduction in emissions from existing sources in the area as may be obtained through the adoption, at a minimum, of reasonably available control technology;

"(4) include a comprehensive, accurate, current inventory of actual emissions from all sources (as provided by rule of the Administrator) of each such pollutant for each such area which is revised and resubmitted as frequently as may be necessary to assure that the requirements of paragraph (3) are met and to assess the need for additional reductions to assure attainment of each standard by the date required under paragraph (1);

"(5) expressly identify and quantity the emissions, if any, of any such pollutant which will be allowed to result from the construction and operation of major new or modified stationary sources for each such area; . . .

.....

"(8) contain emission limitations, schedules of compliance and such other measures as may be necessary to meet the requirements of this section." 91 Stat. 747.

Section 171(1) provided:

"(1) The term `reasonable further progress' means annual incremental reductions in emissions of the applicable air pollutant (including substantial reductions in the early years following approval or promulgation of plan provisions under this part and section 110(a)(2)(I) and regular reductions thereafter) which are sufficient in the judgment of the Administrator, to provide for attainment of the applicable national ambient air quality standard by the date required in section 172(a)." Id., at 746.

[26] Section 171(3) provides:

"(3) The term `lowest achievable emission rate' means for any source, that rate of emissions which reflects —

"(A) the most stringent emission limitation which is contained in the implementation plan of any State for such class or category of source, unless the owner or operator of the proposed source demonstrates that such limitations are not achievable, or

"(B) the most stringent emission limitation which is achieved in practice by such class or category of source, whichever is more stringent.

"In no event shall the application of this term permit a proposed new or modified source to emit any pollutant in excess of the amount allowable under applicable new source standards of performance."

The LAER requirement is defined in terms that make it even more stringent than the applicable new source performance standard developed under § 111 of the Act, as amended by the 1970 statute.

[27] During the floor debates Congressman Waxman remarked that the legislation struck

"a proper balance between environmental controls and economic growth in the dirty air areas of America. . . . There is no other single issue which more clearly poses the conflict between pollution control and new jobs. We have determined that neither need be compromised. . . .

"This is a fair and balanced approach, which will not undermine our economic vitality, or impede achievement of our ultimate environmental objectives." 123 Cong. Rec. 27076 (1977).

The second "main purpose" of the provision — allowing the States "greater flexibility" than the EPA's interpretative Ruling — as well as the reference to the EPA's authority to amend its Ruling in accordance with the intent of the section, is entirely consistent with the view that Congress did not intend to freeze the definition of "source" contained in the existing regulation into a rigid statutory requirement.

[28] In the same Ruling, the EPA added:

"The above exemption is permitted under the SIP because, to be approved under Part D, plan revisions due by January 1979 must contain adopted measures assuring that reasonable further progress will be made. Furthermore, in most circumstances, the measures adopted by January 1979 must be sufficient to actually provide for attainment of the standards by the dates required under the Act, and in all circumstances measures adopted by 1982 must provide for attainment. See Section 172 of the Act and 43 F R 21673-21677 (May 19, 1978). Also, Congress intended under Section 173 of the Act that States would have some latitude to depart from the strict requirements of this Ruling when the State plan is revised and is being carried out in accordance with Part D. Under a Part D plan, therefore, there is less need to subject a modification of an existing facility to LAER and other stringent requirements if the modification is accompanied by sufficient intrasource offsets so that there is no net increase in emissions." 44 Fed. Reg. 3277 (1979).

[29] Id., at 51926. Later in that Ruling, the EPA added:

"However, EPA believes that complete Part D SIPs, which contain adopted and enforceable requirements sufficient to assure attainment, may apply the approach proposed above for PSD, with plant-wide review but no review of individual pieces of equipment. Use of only a plant-wide definition of source will permit plant-wide offsets for avoiding NSR of new or modified pieces of equipment. However, this is only appropriate once a SIP is adopted that will assure the reductions in existing emissions necessary for attainment. See 44 FR 3276 col. 3 (January 16, 1979). If the level of emissions allowed in the SIP is low enough to assure reasonable further progress and attainment, new construction or modifications with enough offset credit to prevent an emission increase should not jeopardize attainment." Id., at 51933.

[30] In its explanation of why the use of the "bubble concept" was especially appropriate in preventing significant deterioration (PSD) in clean air areas, the EPA stated: "In addition, application of the bubble on a plant-wide basis encourages voluntary upgrading of equipment, and growth in productive capacity." Id., at 51932.

[31] "The dual definition also is consistent with Alabama Power and ASARCO. Alabama Power held that EPA had broad discretion to define the constituent terms of `source' so as best to effectuate the purposes of the statute. Different definitions of `source' can therefore be used for different sections of the statute. . . .

"Moreover, Alabama Power and ASARCO taken together suggest that there is a distinction between Clean Air Act programs designed to enhance air quality and those designed only to maintain air quality. . . .

.....

"Promulgation of the dual definition follows the mandate of Alabama Power, which held that, while EPA could not define `source' as a combination of sources, EPA had broad discretion to define `building,' `structure,' `facility,' and `installation' so as to best accomplish the purposes of the Act." 45 Fed. Reg. 52697 (1980).

[32] It stated:

"5. States will remain subject to the requirement that for all nonattainment areas they demonstrate attainment of NAAQS as expeditiously as practicable and show reasonable further progress toward such attainment. Thus, the proposed change in the mandatory scope of nonattainment new source review should not interfere with the fundamental purpose of Part D of the Act.

"6. New Source Performance Standards (NSPS) will continue to apply to many new or modified facilities and will assure use of the most up-to-date pollution control techniques regardless of the applicability of nonattainment area new source review.

"7. In order to avoid nonattainment area new source review, a major plant undergoing modification must show that it will not experience a significant net increase in emissions. Where overall emissions increase significantly, review will continue to be required." 46 Fed. Reg. 16281 (1981).

[33] "What EPA may not do, however, is define all four terms to mean only plants. In the 1980 PSD rules, EPA did just that. EPA compounded the mistake in the 1981 rules here under review, in which it abandoned the dual definition." Brief for Respondents 29, n. 56.

[34] We note that the EPA in fact adopted the language of that definition in its regulations under the permit program. 40 CFR §§ 51.18(j)(1)(i), (ii) (1983).

[35] Since the regulations give the States the option to define an individual unit as a source, see 40 CFR § 51.18(j)(1) (1983), petitioners do not dispute that the terms can be read as respondents suggest.

[36] The argument based on the text of § 173, which defines the permit requirements for nonattainment areas, is a classic example of circular reasoning. One of the permit requirements is that "the proposed source is required to comply with the lowest achievable emission rate" (LAER). Although a State may submit a revised SIP that provides for the waiver of another requirement — the "offset condition" — the SIP may not provide for a waiver of the LAER condition for any proposed source. Respondents argue that the plantwide definition of the term "source" makes it unnecessary for newly constructed units within the plant to satisfy the LAER requirement if their emissions are offset by the reductions achieved by the retirement of older equipment. Thus, according to respondents, the plantwide definition allows what the statute explicitly prohibits — the waiver of the LAER requirement for the newly constructed units. But this argument proves nothing because the statute does not prohibit the waiver unless the proposed new unit is indeed subject to the permit program. If it is not, the statute does not impose the LAER requirement at all and there is not need to reach any waiver question. In other words, § 173 of the statute merely deals with the consequences of the definition of the term "source" and does not define the term.

[37] See supra, at 853. We note that Senator Muskie was not critical of the EPA's use of the "bubble concept" in one NSPS program prior to the 1977 amendments. See ibid.

[38] See, for example, the statement of the New York State Department of Environmental Conservation, pointing out that denying a source owner flexibility in selecting options made it "simpler and cheaper to operate old, more polluting sources than to trade up. . . ." App. 128-129.

[39] "Economists have proposed that economic incentives be substituted for the cumbersome administrative-legal framework. The objective is to make the profit and cost incentives that work so well in the marketplace work for pollution control. . . . [The `bubble' or `netting' concept] is a first attempt in this direction. By giving a plant manager flexibility to find the places and processes within a plant that control emissions most cheaply, pollution control can be achieved more quickly and cheaply." L. Lave & G. Omenn, Cleaning the Air: Reforming the Clean Air Act 28 (1981) (footnote omitted).

[40] Respondents point out if a brand new factory that will emit over 100 tons of pollutants is constructed in a nonattainment area, that plant must obtain a permit pursuant to § 172(b)(6) and in order to do so, it must satisfy the § 173 conditions, including the LAER requirement. Respondents argue if an old plant containing several large emitting units is to be modernized by the replacement of one or more units emitting over 100 tons of pollutant with a new unit emitting less — but still more than 100 tons — the result should be no different simply because "it happens to be built not at a new site, but within a pre-existing plant." Brief for Respondents 4.

[41] See, e. g., Aluminum Co. of America v. Central Lincoln Peoples' Util. Dist., ante, at 390.

[42] See SEC v. Sloan, 436 U. S., at 117; Adamo Wrecking Co. v. United States, 434 U. S. 275, 287, n. 5 (1978); Skidmore v. Swift & Co., 323 U. S. 134, 140 (1944).

[43] See Capital Cities Cable, Inc. v. Crisp, ante, at 699-700; United States v. Shimer, 367 U. S. 374, 382 (1961).