Opinion filed by Chief Judge WALD, in which Circuit Judges SPOTTSWOOD W. ROBINSON, III, MIKVA, HARRY T. EDWARDS, and RUTH BADER GINSBURG join.

Opinion filed by Circuit Judge BUCKLEY, in which Circuit Judges STARR and D.H. GINSBURG join and Circuit Judge WILLIAMS joins in part.

Opinion filed by Circuit Judge SILBERMAN.

Opinion filed by Circuit Judge WILLIAMS.

The en banc court, convened to decide the question of whether petitioners have standing to challenge a rule of the Environmental Protection Agency (EPA) adopting new formulae for calculating automobile fuel efficiency, has divided evenly on whether the standing requirement has been met. In view of this even division, the court has decided to reinstate the original panel decision affirming in part and reversing and remanding in part the EPA's rule. This resolution accords with the policy recently adopted by this circuit that generally leaves intact panel decisions until they are vacated by a majority of the en banc court. However, in light of the division of this en banc court on standing, the court has agreed that neither the reinstatement of the panel decision, nor any of the separate opinions that follow, shall be considered as establishing precedent as to any aspect of standing.

The en banc court also recognizes that the considerable time it has taken for this appeal to proceed may make it unusually difficult for the manufacturers subject to the EPA's rule to satisfy fuel-economy standards as a result of the retroactively readjusted Corporate Average Fuel Economy credit ratings generated by the panel's decision. The court assumes that the National Highway Transportation Safety Board will within the limits of its discretion take this factor into account in its proceedings on remand.

It is so ordered.

WALD, Chief Judge, with whom ROBINSON, MIKVA, HARRY T. EDWARDS and RUTH BADER GINSBURG, Circuit Judges, join:

The only issue of this appeal being reheard en banc is whether the Center for Auto Safety and two other membership organizations that represent consumers of automobiles have standing to challenge an agency rule that compensates automobile manufacturers retroactively for changes in the testing procedures used to measure the fuel economy of each manufacturer's sales fleet. For reasons to follow, we conclude that they do.

In this regard, we differ with Judge Silberman, who would reopen the question of whether automobile consumers can suffer a cognizable injury-in-fact from the reduced production of fuel-efficient vehicles. See infra (opinion of Silberman, J.) (hereinafter "Silberman Opinion"). We also part ways with our four colleagues who have concluded that the petitioners fail to satisfy the causation and redressability prongs of the standing requirement. See infra (opinion of Buckley, J.) (hereinafter "Buckley Opinion"). On this score, we find no constitutionally relevant distinction that differentiates this case from Center for Auto Safety v. National Highway Traffic Safety Administration, 793 F.2d 1322 (D.C.Cir.1986) (CAS I ), a precedent which not only survives this en banc intact but is actively endorsed by all but two members of the en banc court.

CAS I held that the same petitioners who have brought this suit had standing to challenge an agency rule that lowered the minimum average fuel economy standards for light trucks promulgated under the Energy Policy and Conservation Act, Pub.L. No. 94-163, 89 Stat. 871 (1975) (codified as amended in 15 & 42 U.S.C.) ("the EPCA" or "the Act"). The panel in that case reasoned that because petitioners complained of vehicles that would be less fuel-efficient, and because the EPCA's standards are designed to make vehicles more fuel-efficient, "[t]he object of the agency's regulation and the injury are thus directly linked." 793 F.2d at 1334-35. Under challenge in today's case is a different agency rule but one that just as surely undermines fuel economy standards. It does so by relaxing fuel-efficiency testing procedures and thereby providing manufacturers with hundreds of millions of dollars in unearned fuel-economy "credits" that permit those manufacturers to fall below the EPCA's standards without fear of sanctions. In refusing to acknowledge that the effect of the agency's unjustified credit awards is the same as an unlawful lowering of the minimum standards, our colleagues repudiate a cause-and-effect relationship which Congress itself identified when after extensive hearings it selected a monetary incentive system as its means of inducing automobile manufacturers to provide for improved energy efficiency of motor vehicles.

Despite Congress' selection of a penalty-and-credit incentive system, and despite 12 years of regulatory experience under the Act that underscores the effectiveness of this legislative strategy in promoting fuel economy in automobiles, four of our colleagues conclude today that as a matter of constitutional law the unjustified provision of credits toward meeting the fuel economy minimum standards cannot affect the future availability of energy-efficient cars-- i.e., that no major automobile manufacturer will respond to these regulatory incentives and disincentives in the manner Congress expected. We, however, do not believe that Article III of the Constitution requires or even allows judges to substitute their own counterintuitive views of the economic dynamics at work in the automobile industry for those of Congress, any more than the Fourteenth Amendment "enact[s] Mr. Herbert Spencer's Social Statics," Lochner v. New York, 198 U.S. 45, 75, 25 S.Ct. 539, 546, 49 L.Ed. 937 (1905) (Holmes, J., dissenting). Accordingly, we find that these petitioners have identified a cognizable injury that is both caused by the challenged rule and redressable by this court, and we would hold they have standing to bring this appeal.

A. The Incentive Structure Established by the EPCA

The EPCA was a comprehensive legislative response to the energy shocks of the 1973 oil embargo. It sought "to conserve energy supplies through energy conservation programs" and "to provide for improved energy efficiency of motor vehicles, major appliances, and certain other consumer products." 42 U.S.C. Sec. 6201(4) and (5). Throughout its structure and provisions, the Act reflects Congress' firm conviction that economic actors would respond to economic stimuli.

The Act aimed at doubling the 1974 level of automobile fuel efficiency by 1985.1 Toward that end, Congress established mandatory fleetwide Corporate Average Fuel Economy ("CAFE") standards, which required manufacturers to improve by 50% the fuel economy of their fleets by model year ("MY") 1980 and to double that target by MY 1985. Congress delegated to the Department of Transportation (DOT) responsibility for setting annual CAFE standards for automobiles and light trucks in the intervening years.2

To assure compliance with this statutory scheme, Congress imposed a system of financial penalties for companies which fell short of annual CAFE standards, which are measured in miles per gallon. 15 U.S.C. Sec. 2007 (defining as "unlawful conduct" failure to comply with average annual fuel economy standards). A manufacturer must pay a penalty of $5 for each tenth of a mile by which it falls short of the standard, multiplied by the number of automobiles in that manufacturer's sales fleet. 15 U.S.C. Sec. 2008(b)(1)(A).

Congress, however, also wanted to encourage manufacturers to exceed the annual minimum CAFE requirements, and so it provided them with flexibility in planning their production to meet the Act's increasing fuel economy standards. It allowed them to carry their surplus CAFE credits forward and backward to other model years. 15 U.S.C. Sec. 2002(l )(1)(A). Thus, if a manufacturer's CAFE rating for a given year exceeds the minimum requirement for that year, the manufacturer earns CAFE credits (one credit per tenth of a mile by which the standard has been surpassed, multiplied by the number of automobiles it has manufactured that model year). Those credits are then available to offset any penalties incurred in the preceding three model years, or as a cushion against future deficiencies in the subsequent three model years. 15 U.S.C. Sec. 2007(b). In sum, credits earned in any particular year have a six-year model year life during which they permit a manufacturer to fall below CAFE requirements.3

The EPCA vests the Environmental Protection Agency (EPA) with responsibility for conducting the fuel-economy tests on automobile models. In conducting such tests, the agency may use either the procedures utilized for MY 1975, or it may develop testing and calculation procedures "which yield comparable results." 15 U.S.C. Sec. 2003(d)(1). By inserting the comparability requirement, Congress meant to insure that auto manufacturers be credited only with real fuel economy gains, not illusory gains generated by changes in test procedures. To give manufacturers sufficient lead time, Congress also required the EPA to promulgate any revisions in testing procedures other than technical or clerical changes "not less than 12 months prior to the model year to which such procedures apply." 15 U.S.C. Sec. 2003(d)(3).

In 1979, Ford Motor Company ("Ford") and General Motors Corporation ("GM") filed petitions for rulemaking with the EPA. The automobile manufacturers alleged that changes in the EPA's testing procedures since MY 1975 had caused their CAFE ratings to be lower than they would have been under original testing procedures. The companies argued that, although the Act permits changes in testing procedures, Sec. 2003(d)(1) requires the agency to make appropriate adjustments to insure that the resulting fuel economy averages are "comparable" to results which could have been attained under 1975 procedures.

The Administrator of the EPA denied the companies' request, and the companies appealed to the Court of Appeals for the Sixth Circuit. That court remanded the case to the EPA to initiate a rulemaking that would establish an "adjustment factor" reconciling current test procedures with previous ones. See General Motors Corp. v. Costle, Nos. 80-3271, 80-3272, & 80-3655, mem. order (6th Cir.1982); see also General Motors Corp. v. Costle, 698 F.2d 1219 (6th Cir.1982). The court's order left it to the EPA to determine which test procedures required adjustment, and by how much.

In July 1985, the EPA, having reviewed technical data and heard public comment, completed its rulemaking. It granted manufacturer-specific CAFE adjustments to compensate for the adverse impacts of certain changes in test procedures adopted after 1975. These new CAFE adjustment equations applied to automobile CAFE ratings from MY 1980 through MY 1984. The EPA also adopted one prospective-only adjustment, and established regulations designed to maintain the stringency of the CAFE standards in future model years. See 48 Fed.Reg. 56,526 (1983) (notice of proposed rulemaking); 49 Fed.Reg. 48,024 (1984) (supplemental notice of proposed rulemaking); 50 Fed.Reg. 27,172 (1985) (final rule).

The effect of these rulings was to provide Ford and GM with CAFE credits worth hundreds of millions of dollars. No complete figures totalling those credits can be found in the record of this case, but a December 1985 letter from NHTSA to GM is instructive. It estimated that the retroactive change in testing procedures would draw down GM's net liability in MY 1984 (when GM failed to meet the CAFE standards) to $508.7 million from its previous level of $629.8 million, while increasing GM's net credit surplus in MY 1981 and MY 1982 (when GM exceeded the CAFE standards) to $462.4 from $274.2 million. See Letter from Administrator of NHTSA to GM (Dec. 30, 1985) (reprinted in Addendum to Reply Brief for Petitioners).

The petitioners in this action, filed on August 20, 1985 in this court pursuant to 15 U.S.C. Sec. 2004(a), are four nonprofit membership organizations that promote energy conservation. Three of these groups--the Center for Auto Safety, Public Citizen, and the Union of Concerned Scientists--argue that if the EPA's adjustments are left intact, their members will be injured

because [the rule] retroactively gives manufacturers credits for higher fuel economy ratings which are worth an estimated $540 million to General Motors and $245 million to Ford. These credits, which relieve manufacturers from liability for their failure to meet federal mileage standards, diminish manufacturers' incentives to develop and market a wider range of fuel-efficient vehicles sought by petitioners' members.

Brief for Petitioners at 43. In short, "consumers are injured because automobiles save less energy and use more gasoline than Congress intended." Supplemental Brief for Petitioners on Rehearing En Banc at 7. The fourth petitioner, Environmental Policy Institute, alleges that its "institutional interests in promoting conservation in [the automobile] and other industries are adversely affected by the EPA's decision, insofar as it diminishes incentives for conservation in this industry, which is a major user of petroleum." Id. at 5.

The essence of the claims of these groups is (1) that the EPA lacked authority to promulgate retroactive CAFE adjustments, because the EPCA requires the agency to provide 12 months notice before making such changes in "testing or calculation procedures," see Sec. 2003(d)(3); and (2) that it was unlawful for the EPA retroactively to apply adjustments favorable to automobile manufacturers at the same time it refused to apply retroactively negative CAFE adjustments reflecting changes in testing procedures that may have unduly benefitted manufacturers. The petitioners offered two examples of negative adjustments that if applied would decrease past CAFE credits but which the EPA proposed to apply only prospectively: one dealing with road load power settings and the other with mileage accumulation limits. It is conceded that if the EPA made these negative adjustments retroactive, most or all of the positive CAFE adjustments awarded to manufacturers under the new rulemaking would have cancelled out.

In an opinion issued December 2, 1986, a panel of this court, relying on CAS I, unanimously held that petitioners had standing to bring suit and that the EPA's refusal to make retroactive negative adjustments in CAFE ratings was error. In so concluding, the panel wrote that "[t]he EPA's decision to award manufacturers CAFE credits ... and to refrain from debiting them for retroactive changes, removes substantial financial incentives to produce more fuel-efficient vehicles in the future." See Center for Auto Safety v. Thomas, 806 F.2d 1071, 1075 (D.C.Cir.1986).4

On February 6, 1987, the full court vacated the panel opinion and granted rehearing en banc, limited to the question: "Does the Center for Auto Safety have standing to challenge the EPA's actions at issue in this case?" See Center for Auto Safety v. Thomas, 810 F.2d 302 (1987). To that question we now turn.

The requirement that a litigant have standing to invoke the power of a federal court "involves both constitutional limitations on federal-court jurisdiction and prudential limitations on its exercise." Warth v. Seldin, 422 U.S. 490, 498, 95 S.Ct. 2197, 2205, 45 L.Ed.2d 343 (1975). The Supreme Court has construed the constitutional limitations, which emanate from the "case or controversy" language of Article III, as containing three distinct yet interrelated requirements. A litigant must demonstrate (1) an actual or threatened injury (2) traceable to the challenged action and (3) likely to be redressed by a favorable decision. The prudential limitations on standing include general prohibitions on a litigant's asserting another person's legal rights and on the adjudication of generalized grievances, as well as the requirement that a plaintiff's complaint fall within the "zone of interests" of the law in question. See Valley Forge Christian College v. Americans United for Separation of Church and State, 454 U.S. 464, 472, 102 S.Ct. 752, 758, 70 L.Ed.2d 700 (1982) (citations omitted); Allen v. Wright, 468 U.S. 737, 751, 104 S.Ct. 3315, 3324, 82 L.Ed.2d 556 (1984).

This case involves only the constitutional components of the standing requirement. Congress may eclipse prudential standing limitations by "grant[ing] an express right of action to persons who would otherwise be barred by prudential standing rules." See Warth, 422 U.S. at 501, 95 S.Ct. at 2206. As this court has held, Congress did precisely that here, by including in the EPCA a provision entitling "[a]ny person who may be adversely affected" by an agency rule passed pursuant to the Act to seek review. 15 U.S.C. Sec. 2004(a) (1982). See CAS I, 793 F.2d at 1336 ("EPCA clearly removes the judicial authority to create prudential barriers"); see also id. at 1336-37 (listing numerous cases construing similar provisions to eclipse the prudential standing barrier); National Wildlife Federation v. Hodel, 839 F.2d 694, 704 n. 7 (D.C.Cir.1988) (also construing statutory provision authorizing suits by "adversely affected" persons to obviate prudential standing limitations). We therefore need evaluate petitioners' standing only in light of Article III's requirements.5

Three of the four petitioners in this case--the Center for Auto Safety (CAS), Public Citizen, and the Union of Concerned Scientists (UCS)--are organizations which represent automobile consumers, on whose behalf they claim standing. The essence of these organizations' complaints is that the provision of fuel-economy credits to Ford and GM will reduce the companies' incentive to develop and market the fuel-efficient vehicles sought by organization members. See supra. If the EPA's final rule is set aside and its provisions of credits rescinded, these petitioners argue, this fuel-saving incentive will be restored and the interest of their members in purchasing the most fuel-efficient vehicles possible will be vindicated.6

In International Union, UAW v. Brock, 477 U.S. 274, 106 S.Ct. 2523, 91 L.Ed.2d 228 (1986), the Supreme Court recently reaffirmed the three-part test for representational standing initially set forth in Hunt v. Washington Apple Advertising Commission, 432 U.S. 333, 97 S.Ct. 2434, 53 L.Ed.2d 383 (1977):

[A]n association has standing to bring suit on behalf of its members when: (a) its members would otherwise have standing to sue in their own right; (b) the interests it seeks to protect are germane to the organization's purpose; and (c) neither the claim asserted nor the relief requested requires the participation of individual members in the lawsuit.

UAW, 477 U.S. at 282, 106 S.Ct. at 2525 (quoting Hunt, 432 U.S. at 343, 97 S.Ct. at 2441). In this case, as in CAS I, it is undisputed that these petitioners satisfy the second and third prongs of the Hunt-UAW test, see CAS I, 793 F.2d at 1329.7 Their standing therefore turns solely on whether the organizations' members satisfy the three prongs of the constitutional standing requirement--injury-in-fact, causation, and redressability--in their own right.

The injury which CAS asserts on behalf of its automobile-consumer members is the diminished availability and price in the automobile market of fuel-efficient vehicles. That is precisely the same injury that a panel of our court (including Judge Buckley) held cognizable in CAS I, 793 F.2d at 1331-34, an opinion whose result and reasoning we reaffirm today. Indeed, eight of the ten members of our court sitting on this appeal reaffirm not only CAS I in general, but the constitutional validity of this particular injury. See Buckley Opinion at 867-68. A ninth member, Judge Williams, reserves judgment on the injury-in-fact question. We therefore focus on injury only to address the alternative and more parsimonious vision of the injury-in-fact requirement offered by the tenth member, Judge Silberman, in his separate opinion.

The essence of Judge Silberman's argument is that CAS has failed to describe with adequate specificity the injury befalling its members. Of the harm CAS has described, he asks, "can it seriously be maintained that the failure to develop a larger number of Ford models than presently exist has resulted in a 'distinct and palpable,' 'particular and concrete,' 'specific and objective' injury?" Silberman Opinion at 878 (emphasis in original). What petitioners have failed to do, Judge Silberman states, is to "identify any particular model, component or performance standard their members seek but cannot find." Id. at 877. From such a failure he concludes that "[t]his is really the case of the missing plaintiff," id. at 882, and that the claim CAS advances here can only be regarded as seeking to vindicate "a political or ideological interest," id., and hence noncognizable under Valley Forge, 454 U.S. at 482-87, 102 S.Ct. at 763-66.

Judge Silberman, however, attacks a straw man. To Judge Silberman, the only injury befalling automobile consumers is "the failure of automobile manufacturers 'to develop and market a wider range of fuel-efficient vehicles.' " Id. at 877 (quoting, and adding emphasis to, Brief for Petitioners at 5). But that is only a small part of the story. In addition to protesting the diminished range of fuel-saving cars, CAS has also alleged that when NHTSA impermissibly lowers a fuel economy standard, or when the EPA takes actions like the one challenged here that encourage manufacturers to overstate the fuel economy of their fleet in measuring it against the Act's goals, there results a diminished number of fuel-saving cars. Those consumers who are shut out or priced out of this constricted market "are injured because [their] automobiles save less energy and use more gasoline than Congress intended." Supplemental Brief for Petitioners on Rehearing En Banc at 7.8

What CAS is saying is simply that, as a result of the EPA's illegal action, its members will have to pay more money to obtain identical mileage. Judge Silberman's caricature notwithstanding, this injury is apart from the sheer number of vehicle models available, and it occurs in one of two ways. First, those consumers seeking to buy fuel-efficient cars will find that the prices of all cars more fuel-efficient than the EPA's CAFE goal have generally been driven up. This result adheres because, after EPA's rule bestowing a bank of CAFE credits on automobile manufacturers, they will have less incentive to manufacture as large a supply of such fuel-efficient cars. As the supply of a good drops, demand remaining constant, the laws of supply and demand would ordinarily suggest its price will rise.9 Second, those automobile consumers who have purchased cars that are relatively less fuel-efficient as a result of auto makers' changed offerings and prices will require more gasoline and therefore pay more money for fuel.10

Price increases like these are classically cognizable economic injuries. See, e.g., Bryant v. Yellen, 447 U.S. 352, 357 & n. 17, 100 S.Ct. 2232, 2235 & n. 17, 65 L.Ed.2d 184 (1980) (residents and would-be purchasers injured by higher farmland prices). Indeed, our circuit has repeatedly recognized that consumers alleging higher prices as a result of government action have pleaded a valid injury-in-fact. See, e.g., Common Cause v. Department of Energy, 702 F.2d 245, 250-51 (1983) (consumers of "energy products" who challenged energy-consumption practices of federal government and alleged "shortages and higher prices of energy products" stated cognizable injury-in-fact); State of Illinois v. Bristol-Myers Co., 470 F.2d 1276, 1278 (D.C.Cir.1972) (state has standing to challenge alleged Sherman Act violations of drug manufacturer on behalf of private consumers who would be injured by higher prices of prescription drugs); Goodman v. Public Service Commission, 467 F.2d 375, 378 (D.C.Cir.1972) (consumer has standing to challenge electric company's price increase); see also Environmental Defense Fund, Inc. v. Hardin, 428 F.2d 1093, 1096-97 (D.C.Cir.1970) (footnotes omitted) ("[c]onsumers of regulated products and services have standing to protect the public interest in the proper administration of a regulatory system enacted for their benefits. The interest asserted in such a challenge to administrative action need not be economic"). This position derives strength from the Supreme Court's admonition that injuries are no less cognizable because they befall the many, not the few. See note 5, supra. And it draws support from the long line of cases in which consumers have been found to have standing to challenge broadly suffered noneconomic injuries. See, e.g., Cutler v. Hayes, 818 F.2d 879, 887-90 (D.C.Cir.1987) (consumers concerned about safety and effectiveness of over-the-counter drugs have standing to challenge certain Food & Drug Administration regulations); Consumers Union of United States, Inc. v. Federal Trade Commission, 691 F.2d 575 (D.C.Cir.1982) ("consumers, in this instance, used-car purchasers, have standing to challenge legislative veto that scuttled an agency rule that would require disclosure "that would assist them in making informed purchasing decisions").

Now one may, as does Judge Buckley, mount an attack on petitioners' standing on the theory that any such price increases are so indirectly related to the EPA's action that they may never occur, and so cannot survive the Supreme Court's "substantial likelihood" test for causation. See infra; see also Common Cause, 702 F.2d at 252 (finding injury-in-fact but denying standing to consumer litigants alleging price injury because chain of events alleged to produce price increases was "conjectural at best"). But it is far too late in the day to question a price increase befalling a consumer as a result of state action as a cognizable injury. Suppose for a moment that the EPA rule under challenge had been a simple order requiring auto manufacturers to add $100 to the sticker prices of all cars whose performance exceeded the annual fleet fuel economy average. Could anyone seriously question that the resulting price increase would be cognizable?11

Judge Silberman evades grappling with the price-increase injury, and instead confines himself to CAS's separate allegation that the EPA's action is likely to deter production of a "wider range" of automobiles. On that score, he faults CAS for failing to identify the particular models and components whose diminution--or, presumably, whose enhanced prices--its members fear: "a station wagon that achieves over 33 miles per gallon, or a subcompact that gets 45 miles a gallon, or a car with a more efficient automatic transmission system." Silberman Opinion at 3. Make no mistake about the result of this addition to the standing requirement: it would render wholly nonjusticiable all consumer claims raised under the EPCA. For until Ford and GM actually settle upon business strategies for how to alter their production and pricing (and thereby reduce their fuel-economy averages) in response to the EPA's provision of fuel economy credits, no consumer could say with certainty which particular models and components will be phased out and which will evade the boardroom executioner. All a consumer could realistically conclude is that the class of relatively fuel-efficient cars will as a collectivity suffer.

To be sure, his complaint could guess at the vehicular victims: the 33 mpg station wagon, for example, or the gas-stingy subcompact, or the pink Cadillac with crushed velvet seats. But requiring the naming of automobile types for the mere sake of the appearance of specificity would be just the sort of "mechanical exercise" in applying the standing requirement that the Supreme Court has quite recently warned against. See Pennell v. City of San Jose, --- U.S. ----, ----, 108 S.Ct. 849, 854, 99 L.Ed.2d 1 (1988) (majority opinion of Rehnquist, C.J.) (quoting Allen, 468 U.S. at 751, 104 S.Ct. at 3324). It would be an especially empty gesture because CAS's consumer members pointedly disavow reflexive brand loyalty in favor of value, a concept that is meaningless before one knows the price of a particular item. And because no one could say it is substantially likely that a particular model will be deemphasized--even though many models are likely to be, and even though the aggregate production of the more fuel-efficient members of a manufacturer's fleet is almost certain to drop--the "33 mpg station wagon" complaint would ultimately fail the causation prong of the standing requirement. Between the Scylla of the imprecise injury and the Charybdis of the uncertain occurrence, all consumer complaints based on the EPCA would founder.

That would be a remarkable result. For while it is true that there may be causes of action which no one has standing to bring, see Valley Forge, 454 U.S. at 489, 102 S.Ct. at 767, the Supreme Court has never found such total nonjusticiability in a case in which petitioners alleged tangible economic (as opposed to ideological or psychological) injury, or for that matter in a case involving a statute in which Congress had eliminated all prudential barriers to standing. See supra. This is no generalized grievance based simply on taxpayer status, as in Valley Forge, nor an abstract ideological complaint grounded in citizen status, as in Schlesinger v. Reservists Committee to Stop the War, 418 U.S. 208, 94 S.Ct. 2925, 41 L.Ed.2d 706 (1974). It is a complaint lodged by an identifiable group of people who fear a specific economic injury: reduced car availability, and higher car and gas prices.12

Despite Judge Silberman's call for precision prognostication in pleading, he shrugs off the very case authority that most surely disposes of his argument. For while he derives much rhetorical mileage from the various verbal formulations with which the injury-in-fact requirement has been characterized--that an injury be "distinct and palpable," "particular and concrete," "specific and objective," and so forth, see, e.g., Silberman Opinion at 876--when he comes to consider the actual holdings of the cases involving environmental grievances in which the Supreme Court has given much of its applied content to those standing-doctrine adjectives, his embrace of authority becomes far less enthusiastic. Consider the following passage:

I do not believe the reasoning of these [environmental] cases applies where, as here, only a consumer interest is asserted, for there appears to be some tension between the Supreme Court's standing analysis used in environmental cases and that employed in virtually all other cases.... [T]he court has assumed sub silentio that all parts of the environment are unique and precious to those parts.

... [T]o extend the environmental concept of injury over the consumer preferences would be to trivialize it. An automobile or a particular brand of wrist-watch or even a kind of battery may be unique in some sense and thus gain consumer loyalty, but to say a reduction in its supply causes injury as does the threatened disappearance of a species is to confuse the variety of goods manufactured by man with that which nature produces. In poetic terms, since "only God can make a tree," a person who enjoys sitting under it is uniquely injured by its destruction; man cannot replace that exact tree.

Id. at 883-84 (citations and footnotes omitted).

No authority of which we are aware even remotely supports the hierarchy of Article III values which Judge Silberman, relying on the "sub silentio" assumptions of the Supreme Court, would enshrine. Putting aside the metaphysical difficulties of causation analysis that a judicial distinction between God-created items and manmade goods would involve,13 the elevation of nonmonetizable environmental interests over all others is his theory alone. Case authority on standing jurisprudence if anything suggests the opposite, i.e., the historic primacy of injuries to economic interests. See, e.g., Valley Forge, 454 U.S. at 486, 102 S.Ct. at 765-66. Only with the explosion of environmental litigation in the past two decades did the Supreme Court, in cases like Sierra Club v. Morton, 405 U.S. 727, 92 S.Ct. 1361, 31 L.Ed.2d 636 (1972), United States v. Students Challenging Regulatory Agency Procedures (SCRAP), 412 U.S. 669, 93 S.Ct. 2405, 37 L.Ed.2d 254 (1973), Duke Power Co. v. Carolina Environmental Study Group, 438 U.S. 59, 98 S.Ct. 2620, 57 L.Ed.2d 595 (1978), and Japan Whaling Association v. American Cetacean Society, 478 U.S. 221, 106 S.Ct. 2860, 92 L.Ed.2d 166 (1986), formally recognize the equal legitimacy of aesthetic and environmental values. See, e.g., SCRAP, 412 U.S. at 686, 93 S.Ct. at 2415 ("standing [is] not confined to those who could show 'economic harm' "). It would be surprising indeed to find that those interests had, sub rosa, overtaken economic interests in the Supreme Court's pantheon of Article III values to the point where a more liberal test of cognizability governs them alone.

The fact is that the reduction of options from which a consumer can select in the automobile marketplace, even before it is possible to identify precisely which options will diminish or disappear, is an injury that comfortably accords with the Supreme Court's standing precedents. The cases presenting the most compelling analogy are obviously those involving the government-provoked diminution of unspecified environmental riches. The student plaintiffs in SCRAP pinpointed no particular tree, or even a particular park, and indeed no area smaller than the city of Washington, D.C., which they feared would be ultimately marred by litter as a result of the railroad rate increase they challenged. The wildlife conservation groups in Japan Whaling Association identified no particular whales, or species of whales, or whale habitat smaller than the North Pacific in complaining about American under-enforcement of statutory whaling quotas. Yet both those groups had standing. The consumers who complained of higher prices in Common Cause did not identify specific goods, but rather complained generally about higher prices for "energy products." 702 F.2d at 251. They too pleaded a cognizable injury-in-fact.

We could go on, but the broader point is that the standing requirement is not meant to reserve the federal courts for the clairvoyant. The petitioners here have asserted that they are likely to pay higher prices for, and have greater difficulty finding, the fuel-efficient vehicles they desire if the EPA's action stands. That injury, as we held in CAS I and reaffirm today, is enough.

The second, causation prong of the constitutional standing requirement mandates that the injury alleged be "fairly traceable" to the allegedly illegal conduct under review. See Valley Forge, 454 U.S. at 472, 102 S.Ct. at 758. The third prong, redressability, asks whether the relief requested is likely to redress the alleged injuries. Id. Because the causation and redressability inquiries substantially overlap where, as here, the relief requested is merely the cessation of illegal conduct, see Allen, 468 U.S. at 753 n. 19, 104 S.Ct. at 3325 n. 19. Haitian Refugee Center v. Gracey, 809 F.2d 794, 801 (D.C.Cir.1987), we address causation and redressability together. However, we postpone until the end of our analysis a unique redressability concern created by the length of time it has taken this appeal to proceed.

In CAS I, we held that the injuries to automobile consumers alleged by petitioners were fairly traceable to NHTSA's actions directly lowering fuel-efficiency standards. Petitioners here urge that the same injuries can fairly be traced to the EPA's decision to adjust testing procedures and thereby award CAFE credits worth hundreds of millions of dollars to Ford and GM. The EPA, along with our four colleagues, urges, however, that the relaxation of automobile testing procedures applicable in previous years could not have affected the automobile companies' behavior after August 20, 1985, the date petitioners filed their petition for review of the July 1, 1985 final order. See Buckley Opinion at 871-72. Thus, it is argued that the EPA's rule, whether or not legally correct, could have caused no injury.

We find that the petitioners have satisfied the causation requirement in this case. It is hornbook law that a litigant need not prove causation with absolute certainty in order to have standing: only a "substantial likelihood" that the allegedly unlawful action would cause injury is required. Duke Power Co., 438 U.S. at 75 n. 20, 98 S.Ct. at 2631 n. 20 (1978); Warth, 422 U.S. at 504, 95 S.Ct. at 2208 (1975). Thus, in 1978 the Supreme Court synthesized its past standing decisions and concluded: "[n]othing in our prior cases requires a party seeking to invoke federal jurisdiction to negate the kind of speculative and hypothetical possibilities suggested in order to demonstrate the likely effectiveness of judicial relief." Duke Power Co., 438 U.S. at 78, 98 S.Ct. at 2633. The Court's decisions upholding standing in the ensuing decade have, if anything, underscored the importance of maintaining a practical reading of the causation requirement that mandates not a certain cause-and-effect relationship between government action and alleged injury, but rather only a substantially likely one.14

The intervenors' suggestions to the contrary, the causation requirement is not more rigid when the injury alleged is one that would be worked through the intervention or action of a third party: here, the automobile manufacturer responding to the CAFE credits generated by the EPA's relaxed testing procedures. Rather, the "substantial likelihood" standard governs such cases as well. As we have recently observed, "[t]he Supreme Court's decisions on this point show that mere indirectness of causation is no barrier to standing, and thus an injury worked on one party by another through a third party intermediary may suffice." National Wildlife Federation ("NWF"), 839 F.2d at 705, (citing, inter alia, Meese v. Keene, --- U.S. ----, 107 S.Ct. 1862, 95 L.Ed.2d 415 (1986); Japan Whaling Association; and Duke Power Co.). See also NWF, 839 F.2d at 706-09; Humane Society v. Hodel, 840 F.2d 45, 51 n. 5 (D.C.Cir.1988).

We have little difficulty concluding that the EPA's decision retroactively to relax aspects of its testing procedures is "substantially likely," see Duke Power Co., 438 U.S. at 75 n. 20, 98 S.Ct. at 2631 n. 20, to lessen the availability of fuel-efficient cars to petitioners' consumer members. The central fact about the EPA's final rule is that it results in the provision to Ford and GM of CAFE credits worth hundreds of millions of dollars. Not only common sense and elementary economic logic, but also congressional fact-finding compel the conclusion here that the receipt of these massive credits will almost certainly diminish the future (i.e., post-August 1985) availability of fuel-efficient cars to consumers.

In passing, and amending, the EPCA, Congress repeatedly stated that the Act's credit carryforward and carrybackward provisions were designed to work in tandem with the annual fuel-economy standards to induce the production of more fuel-efficient vehicles. Indeed, the legislative history of the EPCA and its amendments makes abundantly clear Congress' assumption that the penalty-and-credit enforcement mechanisms would induce auto makers to exceed minimum fuel standards in order to compensate for unanticipated deficiencies in other years. Thus, if either insufficient penalties are assessed, or excessive CAFE credits are awarded, Congress' objectives will equally be frustrated.

The House Committee report on the 1980 EPCA amendment that extended the carryback-carryforward period from one to three years depicts the credit provision as an integral part of an incentive system intended to promote automotive fuel efficiency:

The Committee stresses that the objective of the [extended credit-carrying period] proposal is to improve flexibility, provide better planning and encourage the manufacturers to exceed the standards.... As a matter of fact, the Committee believes these changes will act as an incentive to manufacturers to exceed the standards now set whenever they can in order to build up credits to act as safeguards against shortfalls that might occur in the future.

H.R.Rep. No. 1026, 96th Cong., 2d Sess. 19-20 (1980), U.S.Code Cong. & Admin.News 1980, pp. 3845, 3858 (emphasis added). There is no question but that the penalties and credits were designed as regulatory carrots and sticks to "provide greater incentives for exceeding standards and ... provide greater flexibility to manufacturers in developing plans to meet standards." Id. at 19, U.S.Code Cong. & Admin.News 1980, p. 3858 (emphasis added); see also id. at 10-11, U.S.Code Cong. & Admin.News 1980, p. 3849 ("With these amendment, manufacturers should have sufficient flexibility to achieve automobile fuel economy standards and, hopefully, to do better. The Committee expects them to do so.") (emphasis added). The Senate Committee report likewise notes that the credit carryforward system would encourage manufacturers who had fallen short of CAFE standards within the previous three years to exceed them in the present year or in future years, rather than simply pay a "massive civil penalty." See S.Rep. No. 642, 96th Cong., 2d Sess. 7 (1980).

We are consequently confounded by statements of our colleagues opposing standing that the credit carryback and carryforward provisions of the Act were not at all designed to be "technology-forcing," see Buckley Opinion at 875, but solely to accommodate "considerations of fairness and the need for flexibility," see id. at 875. The legislative history, as well as economic and just plain common sense (the latter two are not always coextensive) flatly contradict any such assertion. The penalty-and-credit provisions were specifically aimed at modifying the behavior of car manufacturers, in order to accomplish the fuel-saving objectives of Congress. Indeed, CAS I itself--a precedent embraced by our four colleagues--recognizes that the penalty-and-credit provisions are inseparable parts of a statutory package geared toward spurring enhanced fuel-economy:

EPCA's system of penalties, coupled with credits that can be carried forward or backward three years, serves to force manufacturers to make improvements in the future if they fail to make them in the present.

793 F.2d at 1334 (emphasis added).

Congress' determination that its credit-penalty carryover system would in fact spur fuel-economy gains deserves considerable deference. In refusing to credit Congress' fact-finding, our colleagues blink a long line of decisions relying on such legislative determinations in the context of standing inquires. See, e.g., NWF, 839 F.2d at 708-09 ("while Congress cannot create standing on its own, it can provide legislative assessments which courts can credit in making standing determinations"); Autolog v. Regan, 731 F.2d 25, 26, 31 (D.C.Cir.1984) ("[T]he premise that exclusion of foreign flag shippers will prompt domestic shippers to exploit existing markets for coastwise shipping undergirds the structure of the coastwise laws; we must give great weight to this congressional finding in our standing inquiry."); International Ladies Garment Workers Union v. Donovan, 722 F.2d 795, 811-12 (D.C.Cir.1983), cert. denied, 469 U.S. 820, 105 S.Ct. 93, 83 L.Ed.2d 39 (1984) ("ILGWU ") ("[A]s Congress passed the Act partly to provide redress to employers from unfair competition, the suggestion that effective enforcement of the Act will not have this effect directly contravenes the congressional judgment underlying the Act."); Animal Welfare Institute v. Kreps, 561 F.2d 1002, 1010 (D.C.Cir.1977) ("Congress, in enacting the MMPA, established as a matter of law the requisite causal relationship between American importing practices and South African sealing practices."). The issue is not whether "Congress [can] abrogate the Art. III minima." See Buckley Opinion at 874. It is rather whether, in appraising the likely impact of a complex economic regulatory scheme, the federal judiciary should override congressional factfinding and substitute its own predictions.15

Congressional fact-finding in the standing context of this case carries special weight because it is supported by elementary economic logic and by more than a decade of validating experience in which auto manufacturers have responded to a surplus of CAFE credits by falling short of fuel-economy standards in subsequent years.16 The retroactive credits awarded in this case just as surely altered the economic calculus on which Ford and GM based their fuel-economy decisions after August 1985. Just as penalizing a company for falling short of NHTSA's MY 1984 fuel-economy goals creates an economic incentive for it to exceed standards in MYs 1985, 1986 and 1987, the EPA's decision to draw down Ford's and GM's MY 1984 and MY 1985 debits reduces the incentives for these companies to exceed fuel economy standards during the three-year carryforward periods that run through MY 1987 and 1988, respectively. The EPA's decision bestowing such credits would thus seem, as in CAS I, to make it "substantially likel[y]," see Duke Power Co., 438 U.S. at 75 n. 20, 98 S.Ct. at 2631 n. 20, that the beneficiaries will produce fewer fuel-efficient cars in MY 1987 and MY 1988, thereby causing the loss of consumer opportunities alleged by petitioners. See also CAS I, 793 F.2d at 1334-35 ("if setting a higher standard cannot result in vehicles with increased fuel efficiency, then the entire regulatory scheme is pointless").

This likelihood is enhanced by the record fact that Ford and GM have separately told NHTSA that they will not engage in "unlawful conduct" under 15 U.S.C. Sec. 2008, including allowing their fleets to fall short of CAFE standards in the absence of sufficient credits to avoid paying penalties. See, e.g., Statement of General Motors Corp. to NHTSA, Aug. 8, 1985, at 5 ("GM does not consider the payment of civil penalties to be a reasonable alternative"); Statement of Ford Motor Co. to NHTSA, Aug. 8, 1985, at 7 ("Ford, along with others, have said [sic] many times that the 'unlawful conduct' provision of EPCA precludes planning to pay fines as an alternative to CAFE compliance.... [W]e reaffirm that position today") (both statements included in Addendum to Reply Brief for Petitioners). This means that without the challenged credits, both Ford and GM would almost certainly have moved aggressively to produce more fuel-efficient cars.

The principal objection to this causation rationale raised by our four colleagues opposing standing turns on the long lead times supposedly required for new automobiles to be designed. These lead times are said to make it "highly unlikely" that the downward adjustment of credits by the EPA for MY 1984 and MY 1985 would "force the manufacturers to redesign MY 1987 and MY 1988 autos." Buckley Opinion at 19. That argument fails. First, by misapprehending the operation of the credit carryback-carryforward provisions of the EPCA, it underestimates the future impact of the provision of compensatory credits. Secondly, it ignores the undisputed reality that as of August 20, 1985--the date petitioners sought review of the EPA's order, and thus the initially relevant time at which petitioners' standing is to be analyzed--Ford and GM could have immediately taken numerous steps short of a wholesale "redesign" of their vehicles that would have benefitted fuel economy minded future car owners and compensated for the downward adjustments petitioners demanded. The most obvious such step was, of course, to increase the supply of the more fuel-efficient vehicles. These options, in fact, still existed as of the time the panel opinion issued in December 1986.

Our colleagues assume that MY 1987 and MY 1988 are the outside years in which a change in Ford's and GM's MY 1984 and MY 1985 fuel-economy credits could affect the auto manufacturers' behavior under the carryforward scheme. That assumption, however, is wrong. The EPCA's provision allowing credits to be carried backward three years and forward three years means that the provision of credits for any given year can have repercussions over the next six years, a fact we illustrate by evaluating the effect of the MY 1984 credits as an example. Petitioners seek to rescind the credits allegedly improperly granted to Ford and GM in MY 1984. In order to make up the deficit aggravated by that rescission, the companies would in essence have to "mortgage" any credits they might earn through successful fuel-economies gained in MYs 1985, 1986 and 1987; that is, they would have to carry back these expected credits. As a result, any such credits would not be available to be carried forward from those years to MYs 1988, 1989 and 1990 as they otherwise might have been. (By the same token, rescission of the MY 1985 credits granted by EPA would affect fuel-economy incentives through MY 1991.) Whatever the barriers to changing MY 1987 and MY 1988 vehicles as of August 20, 1985, it is uncontested that, by MY 1990 and MY 1991, the auto manufacturers could have redesigned their vehicle offerings to enhance fuel economy.

Thus, rescinding the massive fuel-economy credits earned by Ford and GM in MY 1984 and MY 1985 makes it substantially more likely that the automobile companies will work to enhance fuel-efficiency in their products in the ensuing six motor-vehicle years. By granting the relief petitioners seek, this court would strip Ford and GM of credits which it could otherwise utilize in the event of a future technological rainy day. Only by generating real fuel-economy gains in the period ending in MY 1991 could the auto manufacturers offset the resulting debits. Such real gains would squarely redress the injury alleged by petitioners.17

In any event, our colleagues' causation and redressability argument against standing, even within their own myopic time frame, is faulty. They claim that at the time petitioners filed for review in August 1985, only 18 months remained before MY 1987 cars were unveiled and only 30 months remained before MY 1988 cars were introduced--too short a time to allow manufacturers to "redesign" planned automobiles so as to introduce fuel-economies. See Buckley Opinion at 872. Thus, after August 1985 a manufacturer could only make "a short-term business decision, not a long-range planning decision" with respect to MY 1987 and MY 1988 vehicles. Id. at 873.

The record provides ample refutation of this aspect of their standing analysis. Although in August 1985 automobile manufacturers may not have been able to "redesign" MY 1987 or MY 1988 vehicles, they could have increased the supply offered of fuel-efficient cars, and they indisputably could have still made important fuel saving changes in their models within that time frame. To meet the standing requirement petitioners need only show a substantial likelihood that auto makers could have taken any steps in response to improve the overall fuel-economy of their MY 1987 and MY 1988 offerings, and thereby partially redressed petitioners' injuries. This they have done.

NHTSA's October 1986 report setting forth its fuel economy standards for MY 1987 and MY 1988 demonstrates unambiguously that Ford and GM had the capacity to make short-term modifications that, while technologically modest, would still have enhanced the fuel economy of their MY 1987 and MY 1988 automobiles. See Passenger Automobile Average Fuel Economy Standards for Model Years 1987-88, 51 Fed.Reg. 35,583ff. The specific changes in particular car lines that manufacturers could have made through the application of existing technology included the "install[ation of] a higher number of 4-speed transmissions in certain midsize cars for MY 1987," id. at 35,607; "additional material substitution," id.; the decrease in [aerodynamic] drag coefficients," id., and the "further penetration of front-wheel drive," id. at 35,611. See also id. at 35,606 (summarizing "cost-effective changes practicable for MY 1987 and MY 1988). A Department of Energy report noted by NHTSA confirms the potential for fuel-saving modifications short of redesign, stating that "many technologies that are cost-effective to the consumer have not been introduced in several models in the large and intermediate size classes." Id. at 35,598.

While ultimately concluding that these modifications did not warrant NHTSA's raising its estimation of the "maximum feasible" fleetwide averages, the NHTSA report is nonetheless sufficient to show that it was feasible for automobile manufacturers to make short-term fuel-saving modifications to cars within the relevant time periods, even those posited by our colleagues.18 Their assertion that "[t]he record is filled with contemporary evidence of the insufficiency of these lead times," Buckley Opinion at 871, thus distorts the thrust of NHTSA's report, which pointedly differentiates between "major changes" requiring long lead times and more modest fuel-saving modifications which do not require those spans.19 Moreover, NHTSA did not conclude, as our colleagues inaccurately assert, that of the above-noted proposals, only increasing the number of four-speed transmissions "could be implemented in the relevant time frame." Id. at 872. What NHTSA stated was that "insufficient lead time" existed for manufacturers to make "sufficient enough improvements" to justify a higher CAFE standard--a different question entirely.

Petitioners do not seek the car of the future today. They ask merely that manufacturers make efforts--whether characterized as short- or long-term, as business decisions or planning decisions--to achieve those fuel savings that are feasible and practicable in line with the statutory goals. There were steps, both technological and marketing ones, that could have been taken in late 1985 and even in 1986 to improve the fuel economy of MY 1987 and MY 1988 vehicles, if the pressure of CAFE debits had been invoked. That constitutes a sufficient showing of redressability to support petitioners' suit.20

Our colleagues make a final backstop argument against the petitioners' standing. They suggest in one paragraph that the manufacturers could earn the necessary CAFE credits through a number of means that would not contribute to the fuel efficiency of the cars produced. Those means include "promotion campaigns to stimulate the sale of smaller cars, discontinuance of certain models, 'outsourcing' the production of others by shifting their production overseas, or limiting such energy-consuming options as air conditioning and high performance engines." Buckley Opinion at 872 (citing Intervenors' Brief on Rehearing En Banc at 15; Brief for Respondents on Rehearing En Banc at 17). Alternatively, it is suggested, manufacturers could, as a last resort, opt to pay the monetary penalties instead of redressing petitioners' injuries. Id. at 873.

Those arguments are easily put to one side. First, if auto manufacturers shift the composition of their fleets to increase the proportion of fuel-efficient vehicles or to reduce the prevalence of gas-guzzling options, petitioners' injuries will be redressed at least in part. In order for an auto manufacturer to sell more small cars to bring up its fleetwide CAFE average, it will have to take some action to make those smaller cars relatively more attractive (i.e., decrease their prices). Recent experience suggests that manufacturers engage in a variety of such marketing strategies beyond mere advertising, including offering cash rebates and below-market financing, when they deem it appropriate to promote a particular product line. Such steps, making fuel-efficient cars less expensive, necessarily make such vehicles more accessible to the fuel economy minded.

As to the outsourcing alternative suggested by our colleagues, it would affect our standing analysis only if all manufacturers were to decide either to manufacture all large vehicles abroad or not to comply with the EPCA and instead pay penalties. For if even one large manufacturer complies with NHTSA's standards in any other fashion, petitioners' injuries will have been partly redressed. Given that decisions to manufacture vehicles abroad are based on a number of factors--including foreign trade legislation, provisions in collective bargaining agreements, United States and foreign tax consequences, and foreign investment laws and risks--total collective outsourcing seems a highly unlikely scenario. Although this herd scenario is of course theoretically possible, such economic fancies are legally irrelevant in undertaking Article III standing analysis. See ILGWU, 722 F.2d at 811 (a petitioner "need not negate every conceivable impediment to effective relief no matter how speculative"). Finally, our colleagues' last-ditch scenario that manufacturers would pay the fines rather than comply with the EPCA standards is speculative in the extreme. Representatives of both Ford and GM have stated that the companies do not regard paying civil fines as a viable alternative. See supra.21 Article III of the Constitution hardly compels us to conclude precisely the opposite.

Despite this "what if?" sequence of our colleagues, the causal connection between the EPA's award of retroactive credits (and its refusal to assign corresponding retroactive debits) and the likelihood of optimal fuel economy improvements over the next several years is at least as plausible and secure as those in many recent cases where the Supreme Court has found standing. Indeed, our colleagues brush aside too lightly explicit direction from the Supreme Court as to the limited scope for judicial speculation in standing inquiries involving complex economic and regulatory relationships:

An injunction would not, of course, guarantee that Lincoln Green would be built. MHDC would still have to secure financing, qualify for federal subsidies, and carry through with construction. But all housing developments are subject to some extent to similar uncertainties. When a project is as detailed and specific as Lincoln Green, a court is not required to engage in undue speculation as a predicate for finding that the plaintiff has the requisite personal stake in the controversy. MHDC has shown an injury to itself that is "likely to be redressed by a favorable decision." Simon v. Eastern Ky. Welfare Rights Org., supra, [426 U.S. 26] at 38 [96 S.Ct. 1917, 1924, 48 L.Ed.2d 450] [footnote omitted].

Village of Arlington Heights v. Metropolitan Housing Development Corp., 429 U.S. 252, 261-62, 97 S.Ct. 555, 561, 50 L.Ed.2d 450 (1977) (emphasis added).22 And in ignoring Congress's own assessment that a credit-and-penalty scheme would modify manufacturers' behavior, our four colleagues similarly disregard a long line of Supreme Court guidance counseling against such judicial second-guessing.23

We turn finally to a unique problem of redressability arising not so much from the three-year limitations on credit carryforwards imposed by the EPCA as from the time it has taken this appeal to proceed. More than two-and-a-half years have elapsed since petitioners sought review of the EPA's final rule in August 1985, nearly half of this period having occurred after the initial decision of a panel of this court was handed down. In light of the principle that standing "must exist at all stages of the proceeding, and not merely when the action is initiated or during an initial appeal," Safir v. Dole, 718 F.2d 475, 481 (D.C.Cir.1983) (citing DeFunis v. Odegaard, 416 U.S. 312, 319, 94 S.Ct. 1704, 1707, 40 L.Ed.2d 164 (1974)), the question arises as to whether as of today the petitioners' injury would still likely be redressed by a favorable decision.

We conclude that petitioners' injury remains redressable. As noted previously, the three-year carryback and carryforward provisions give the EPCA an effective six-year reach into the future. If petitioners succeed in modifying the EPA's final rule, they will strip Ford and GM of credits accruing in MY 1984 and MY 1985 and thereby accentuate the deficit those companies recorded in those years. As a result, credits the manufacturers earned in MY 1987 or earn in MY 1988 will be applied retrospectively, to cure the MY 1984 and MY 1985 deficits. Credits so used will thus be unavailable to offset substandard performances in MY 1990 and MY 1991, giving the manufacturers a substantial incentive to improve their fuel efficiency in those two future years. If Ford and GM respond to that incentive, as the congressional incentive scheme clearly contemplates they will, petitioners' injury will be at least partly redressed.

These automobile consumers have standing. The injury they suffer is a traditional economic one: higher prices and diminished availability of the goods they seek. The causal link leading to that injury from the EPA's action is unambiguous: the EPA's provision of massive credits has withdrawn a tremendous financial incentive for car manufacturers to put fuel-saving cars on the market. The redressability inquiry is equally clear: retract the credits and the incentive is restored.

Our dispute today with our colleagues opposing standing, particularly those who do so by finding no cause-and-effect relationship between the EPA's action and consumers' injury, reduces itself to one of fidelity to congressional intent. Congress designed the Energy Policy and Conservation Act as a carefully calibrated incentive system for a reason: it believed that a system of monetary penalties and incentives would be most potent in inducing automobile manufactures to make significant advances in energy conservation. The years since the passage of the EPCA have borne out the wisdom of Congress' market-oriented solution, as automobile companies, including the two implicated in this case, have consistently worked to offset or avoid paying financial penalties and in so doing have achieved impressive fuel economies.

Our determination that the petitioning organizations of automobile consumers have standing in this case respects Congress' determination that economic incentives yield results in the area of automobile fuel economy. The EPA rule challenged by petitioners would compensate manufacturers for fuel economy testing procedures that were allegedly too stringent by granting the manufacturers hundreds of millions of dollars in fuel economy credits. In concluding that petitioners have standing to challenge this rule, we merely reaffirm that the EPCA's penalty-and-credit system is substantially likely to work as Congress expected, and that the provision of hundreds of millions of dollars in fuel economy credits in this case will inevitably dampen auto manufacturers' enthusiasm for aggressively pursuing fuel economy gains.

Our four colleagues reach a different result. Blinking Congress's judgment, the experience of more than a decade under the Act, and the simple logic that economic actors respond to economic stimuli, they conclude that automobile consumers are unlikely to be harmed by the EPA's action and therefore may not have their day in court. We find nothing in Article III of the Constitution, or Supreme Court cases construing Article III to compel this result; indeed, we find in the separation of powers principles that inform Article III, see Allen, 468 U.S. at 750-52, 104 S.Ct. at a mandate to defer to the legislative facts undergirding a congressionally-designed incentive scheme. We would therefore allow petitioners to pursue their challenge.

BUCKLEY, Circuit Judge, with whom STARR and D.H. GINSBURG, Circuit Judges, join, and WILLIAMS, Circuit Judge, joins in part:

Four organizations advocating national fuel conservation policies challenge a rule of the Environmental Protection Agency. The rule increases the Agency's earlier estimates of the fuel efficiency of automobiles sold in the United States in 1980 and subsequent years by adopting new formulae for calculating fuel efficiency that favor automobile manufacturers. The petitioning organizations contend that parts of the rule violate the Energy Policy and Conservation Act of 1975. At issue are several hundred million dollars in automobile efficiency credits generated by the rule.

We granted rehearing en banc to decide whether petitioners have standing. We would hold that the petition must be dismissed for lack of subject matter jurisdiction because it does not present a case or controversy within the meaning of Article III of the Constitution.

In 1973, the Organization of Petroleum Exporting Countries declared an embargo of oil exports to the United States. A sharp increase in world crude prices followed, accompanied by severe shortages of petroleum products in the United States. Congress responded in part by enacting the Energy Policy and Conservation Act ("Act" or "EPCA"). The goal of the Act is to nearly double the number of miles the average new automobile can travel per gallon of gasoline consumed, using cars sold in the United States in model year ("MY") 1974 as a base. The Environmental Protection Agency ("EPA") had calculated that those cars averaged 14 miles per gallon ("mpg"). Congress sought to achieve this goal by imposing, over a ten-year period, a series of graduated mileage requirements that would ensure "wide consumer choice" by leaving "maximum flexibility to the manufacturer" to produce a "diverse product mix." S.Rep. No. 179, 94th Cong., 1st Sess. 6 (1975).

Title III of the EPCA, codified at 15 U.S.C. Secs. 2001-2012 (1982 & Supp. II 1984), prescribes annual increases in "corporate average fuel economy" ("CAFE") standards that automobile manufacturers must achieve. For model years 1978 through 1980, the Act establishes CAFE requirements of 18, 19, and 20 mpg, respectively. 15 U.S.C. Sec. 2002(a)(1) (1982). The standards for model years 1981 through 1984 are to be established by the Secretary of Transportation, who must set them at levels that are the "maximum feasible" for each of such years, and that "will result in steady progress" towards the 27.5 mpg CAFE standard established by the Act for MY 1985. 15 U.S.C. Sec. 2002(a)(3) (1982). Among the factors the Secretary is required to consider in determining maximum feasibility are technological feasibility and economic practicality. 15 U.S.C. Sec. 2002(e) (1982).

The Act also establishes a system of penalties to enforce the mandated standards, and of credits that may be applied to reduce the penalties. The Act places the administration of these penalties and credits in the hands of the Secretary, who has delegated his duties under the Act to the National Highway Traffic Safety Administration ("NHTSA"). Each manufacturer must pay a civil penalty of five dollars for every tenth of a mile its CAFE rating falls short of the applicable fuel economy standard, multiplied by the number of cars it manufactured in the United States that year, reduced by any credits "then available under section 2002(l )." 15 U.S.C. Sec. 2008(b)(1)(B) (1982).

If a manufacturer's CAFE rating exceeds the minimum standard, the Act entitles that manufacturer to receive an appropriate credit. 15 U.S.C. Sec. 2002(l )(1)(B) (1982). Such credit "shall be available to be taken into account" for CAFE deficiencies during the three model years preceding or following the model year in which it is earned. Id. As in the case of a penalty, the amount of the credit earned in a model year is calculated by multiplying the number of cars a manufacturer produced during that year by "the number of tenths of a mile per gallon by which" the manufacturer's CAFE rating exceeds the applicable standard. 15 U.S.C. Sec. 2002(l )(1)(D) (1982).

The Act requires the Administrator of the EPA to establish "testing and calculation procedures" for determining CAFE ratings. The Administrator must follow either the procedures the EPA used to measure automobile fuel efficiency for MY 1975, or other "procedures which yield comparable results." 15 U.S.C. Sec. 2003(d)(1) (1982).

In 1979, General Motors Corporation ("GM") and Ford Motor Company ("Ford") filed petitions for rulemaking with the EPA requesting that it promulgate a CAFE "adjustment factor" for MY 1980 and beyond. They complained that changes in testing procedures adopted by the EPA since 1975 had resulted in lower CAFE ratings than they would have obtained under procedures "comparable," id., to those in effect in 1975. At the time of their request both companies faced substantial EPCA penalties.

The Administrator of the EPA denied the manufacturers' request. They then filed a petition for review in the United States Court of Appeals for the Sixth Circuit. In an unpublished opinion, our sister circuit granted review and remanded the case to the EPA with directions to promulgate appropriate procedures for establishing an adjustment factor. General Motors Corp. v. Costle, Nos. 80-3271, 80-3272 & 80-3655, mem. order (6th Cir. Jan. 26, 1982) (Joint Appendix ("J.A.") at 106); see 698 F.2d 1219 (6th Cir.1982) (report of remand).

On December 21, 1983, the EPA published a notice proposing rules that would apply an industry-wide CAFE adjustment for model years after 1979. 48 Fed.Reg. 56,526 (Dec. 21, 1983) (J.A. at 25) ("NPRM"). A supplemental notice published December 7, 1984, proposed a special industry-wide CAFE adjustment for MY 1981 to reflect the availability of fuel-efficient oils, and an adjustment for model years after 1980 to account for changes in test fuel blend. 49 Fed.Reg. 48,024 (Dec. 7, 1984) (J.A. at 36) ("Supplemental NPRM").

On July 1, 1985, the EPA promulgated a final rule prescribing CAFE adjustment equations that were made applicable to automobile CAFE ratings for model years 1980 through 1984. 50 Fed.Reg. 27,172 (1985) (amending 40 C.F.R. Part 600) (J.A. at 9). The final rule also established changes in testing procedures for the years following MY 1984. Id. at 27,173. The resulting increases in credits earned by GM and Ford enabled them to reduce the large penalties they had incurred in model years 1984 and 1985. The penalties resulted from a significant shift in consumer demand to larger, less fuel-efficient models attributable to an unanticipated drop in the price of gasoline. 51 Fed.Reg. 35,594 (1986). The new rule had a significant impact on the obligations of major manufacturers. For example, before the final rule was issued GM faced a MY 1984 penalty, net of credits carried forward, of $355.6 million. Thanks to the new rule, that penalty was reduced to $46.3 million. Reply Brief at 6.

Petitioners contend that the final rule violates the Act's provisions concerning testing procedures, 15 U.S.C. Sec. 2003(d)(3) (1982) ("Testing and calculation procedures applicable to a model year, and any amendment to such procedures ..., shall be promulgated not less than 12 months prior to the model year to which such procedures apply."). Petitioners argue, in part, that the final rule violates the 12-month requirement because it (1) adjusts CAFE ratings retroactively for model years 1980 and 1981 with respect to four changes in CAFE test procedures identified in the NPRM, and (2) adjusts CAFE ratings retroactively with respect to two test changes identified in the Supplemental NPRM. Opening Brief for Petitioners at 43.

Three petitioners, Center for Auto Safety ("CAS"), Public Citizen, and Union of Concerned Scientists ("UCS"), contend that if the court does not set aside or require modification of the final rule to meet their objections, their members will be

injured ... because [the rule] retroactively gives manufacturers credits for higher fuel economy ratings which are worth an estimated $540 million to General Motors and $245 million to Ford. These credits, which relieve manufacturers from liability for their failure to meet federal mileage standards, diminish manufacturers' incentives to develop and market a wider range of fuel-efficient vehicles sought by petitioners' members.

Id. at 4-5 (footnote omitted). Stated differently, these three petitioners maintain that (1) the challenged rule sharply reduces the large penalties manufacturers had accumulated; (2) those penalties would have forced car makers to earn new credits by achieving greater technological improvements in fuel efficiency than they would otherwise attain; and, therefore, (3) petitioners' members will lose the benefit of a wider choice among more efficient cars on the retail market.

The fourth petitioner, Environmental Policy Institute ("EPI"), alleges only that "[i]ts institutional interests in promoting conservation in this and other industries are adversely affected by EPA's decision, insofar as it diminishes incentives for conservation in this industry, which is a major user of petroleum." Id. at 5. EPI alleges no injury to its members, and fails to identify any of its specific programs that the rule will ostensibly injure.

A panel of this court unanimously held that CAS, Public Citizen, and UCS had standing to bring this action. Center for Auto Safety v. Thomas, 806 F.2d 1071 (D.C.Cir.1986). The panel based its holding on Center for Auto Safety v. National Highway Traffic Safety Admin., 793 F.2d 1322 (D.C.Cir.1986) ("CAS I "), a case arising under related circumstances. The petitioners in CAS I are the same petitioners involved here. Although CAS I concerned light trucks and this case involves passenger cars, the same provisions of the Act concerning motor vehicle fuel efficiency are at issue in both cases.

In CAS I, petitioners challenged NHTSA decisions that lowered minimum average fuel economy standards. In this case, petitioners challenge an EPA decision to raise prior estimates of manufacturers' CAFE ratings which, in turn, resulted in an increase in their credits. The principal issue before us is, in essence, whether this factual difference is of a kind that requires different conclusions as to petitioners' standing to bring these actions.

Because of the significance of the standing issues involved and the need to clarify an important area of the law, on February 6, 1987, the full court vacated the panel opinion and granted rehearing en banc. Center for Auto Safety v. Thomas, 810 F.2d 302 (1987). The court subsequently directed the parties to confine their supplemental briefs to the following question: "Does the Center for Auto Safety have standing to challenge the EPA's actions at issue in this case?" Order, No. 85-1515 (D.C.Cir. filed Feb. 24, 1987). As the panel in this case based its unanimous finding of standing on the panel majority's ruling in CAS I, our review requires that we reexamine that ruling.

Article III of the Constitution limits the exercise of the "judicial Power" of the United States to "Cases" and "Controversies." The Supreme Court has defined the essential elements of a case or controversy as follows:

[A]t an irreducible minimum, Art. III requires the party who invokes the court's authority to "show that he personally has suffered some actual or threatened injury as a result of the putatively illegal conduct of the defendant," and that the injury "fairly can be traced to the challenged action" and "is likely to be redressed by a favorable decision."

Valley Forge Christian College v. Americans United for Separation of Church & State, 454 U.S. 464, 472, 102 S.Ct. 752, 758, 70 L.Ed.2d 700 (1982) (citations omitted). As we noted recently in Haitian Refugee Center v. Gracey, 809 F.2d 794, 799 (D.C.Cir.1987), the first of these three elements "is an injury of the sort which the law will recognize. The other two are stated as varieties of causation: that the injury was not only caused by the action challenged but can be alleviated by that action's cessation."

In the discussion that follows we first examine petitioners' claim of injury and then address causation and redressability.

The first requirement of Article III standing is that petitioners convincingly allege personal, concrete injury. Following applicable Supreme Court precedents, we reject EPI's standing for failure to allege adequate injury. On the other hand, we find the other petitioners have alleged injury that is sufficiently personal and concrete to meet the first part of the Article III standing test.

Petitioner EPI asserts merely that the EPA rule conflicts with its organizational purpose of advocating a national policy favoring fuel conservation. We think this claim is constitutionally insufficient. The Supreme Court has held that organizations can sue on their own behalf if they establish "concrete and demonstrable injury to the organization's activities." Havens Realty Corp. v. Coleman, 455 U.S. 363, 379, 102 S.Ct. 1114, 1124, 71 L.Ed.2d 214 (1982). We have since stated that such organizational standing depends on the organization's "programmatic concerns," and not on its abstract concerns about the achievement of certain national policy goals. Action Alliance of Senior Citizens v. Heckler, 789 F.2d 931, 937 (D.C.Cir.1986). In CAS I, the panel unanimously agreed that EPI had failed to allege injury of the type Article III requires. See 793 F.2d at 1328-29 n. 41; id. at 1342 n. 1 (Scalia, J., dissenting).

EPI's allegation of injury in this case is the same one it made in CAS I. Rather than allege specific, concrete injury to any of its organizational programs or projects, EPI asserts that as a result of the EPA's rule, "[i]ts institutional interests in promoting conservation in this and other industries are adversely affected." Opening Brief for Petitioners at 5. Standing, however, requires a more tangible claim than this. As the Supreme Court noted in Valley Forge, the Constitution "does not provide a special license to roam the country in search of governmental wrongdoing.... The federal courts were simply not constituted as ombudsmen of the general welfare." 454 U.S. at 487, 102 S.Ct. at 766-67 (footnote omitted).

In sum, EPI's complaint has no place in an Article III court. Nevertheless, as the remaining petitioners have alleged a sufficient type of injury, we do not dismiss the case on this basis.

CAS, Public Citizen, and UCS invoke the "associational standing" rule of Hunt v. Washington State Apple Advertising Comm'n, 432 U.S. 333, 342-43, 97 S.Ct. 2434, 2440-41, 53 L.Ed.2d 383 (1977) (construing Warth v. Seldin, 422 U.S. 490, 511, 515, 95 S.Ct. 2197, 2211, 2213, 45 L.Ed.2d 343 (1975)). In Hunt, the Court held that an agency of the State of Washington representing the interests of apple growers could bring suit on their behalf, as if it were "a voluntary membership organization--a typical trade association," 432 U.S. at 342, 97 S.Ct. at 2441, to challenge a North Carolina statute burdening the Washington growers' trade. In reaching its holding, Hunt applied the following three-part requirement for associational standing distilled from Warth:

Thus we have recognized that an association has standing to bring suit on behalf of its members when: (a) its members would otherwise have standing to sue in their own right; (b) the interests it seeks to protect are germane to the organization's purpose; and (c) neither the claim asserted nor the relief requested requires the participation of individual members in the lawsuit.

Id. at 343, 97 S.Ct. at 2441.

Under the Hunt rule, the main issue before us is whether petitioners' members satisfy all parts of the Article III standing requirement. We must apply each part of the standing test separately. On the injury issue, we find this case similar to CAS I. There, the same petitioners attacked a NHTSA rule reducing minimum CAFE levels for light trucks in model years 1985 and 1986. Petitioners' main allegation was that the challenged rules "violated EPCA's requirement that the agency designate standards at 'the maximum feasible [CAFE] level.' " CAS I, 793 F.2d at 1323 (quoting 15 U.S.C. Sec. 2002(b) (1982)). The court held, at the threshold, that

petitioners plainly have standing to bring this action in a representative capacity for members of their organizations. Their members have suffered injury-in-fact because the vehicles available for purchase will likely be less fuel efficient than if the fuel economy standards were more demanding.

Id. at 1324.

After carefully reconsidering CAS I, we agree with the panel's holding that CAS, Public Citizen, and UCS have alleged a constitutionally cognizable type of injury because their members can establish a sufficiently personal and concrete interest in the future availability of vehicles having a greater fuel efficiency than those GM and Ford would otherwise produce. Petitioners state their injury as a reduction in the "range of fuel-efficient vehicles" sought by their members. Opening Brief for Petitioners at 5. While not clearly defined, petitioners' complaint appears to be that as a result of the EPA order, GM and Ford will fail to develop and utilize technologies that would improve the fuel efficiency of their vehicles. Thus, the injury derives from the failure of the manufacturers to enhance the fuel economy of the individual models they market, not from their failure to meet fleet-wide fuel economy standards.

We emphasize, however, that we do not decide whether petitioners have demonstrated adequately that this injury is likely to occur, i.e., is sufficiently real and immediate, not conjectural or hypothetical. City of Los Angeles v. Lyons, 461 U.S. 95, 102, 103 S.Ct. 1660, 1665, 75 L.Ed.2d 675 (1983). We need not determine the likelihood that auto makers will produce a smaller variety of fuel-efficient cars because we conclude that even if this injury is sufficiently real and immediate, it is not likely that it will be caused by the challenged action, or be redressed by a favorable decision.

We reject the other theories of injury to members advanced by petitioners, and we do not interpret CAS I to have approved them. For example, petitioners assert that they represent the consuming public at large, and allege that if the EPA's rule is allowed to stand, the public will not receive the benefits in terms of energy conservation intended by the EPCA. They allege that

[w]hen NHTSA impermissibly lowers a CAFE standard, or when EPA allows auto makers to overstate the fuel economy of their fleet in violation of the "comparability" requirement in 15 U.S.C. Sec. 2003(d)(1), consumers are injured because automobiles save less energy and use more gasoline than Congress intended.

Supplemental Brief for Petitioners at 7. These allegations are constitutionally insufficient.

The fact that Congress has determined that consumers would be injured by driving automobiles that use more rather than less fuel is of little help in determining whether these petitioners are able to establish, on behalf of their members, injuries-in-fact sufficiently personal and concrete to meet the requirements for Article III standing. Even if the EPA's rule results in greater energy use than Congress intended, an agency's failure to "act in accordance with law is not sufficient, standing alone, to confer jurisdiction on a federal court." Allen v. Wright, 468 U.S. 737, 754, 104 S.Ct. 3315, 3326, 82 L.Ed.2d 556 (1984).

Petitioners disagree, asserting that "the injuries here are at least as concrete as those recognized in cases such as United States v. Students Challenging Regulatory Agency Practices [sic], 412 U.S. 669, 93 S.Ct. 2405, 37 L.Ed.2d 254 (1973) ["SCRAP"] ...; Duke Power Co. v. Carolina Environmental Study Group, 438 U.S. 59, 98 S.Ct. 2620, 57 L.Ed.2d 595 (1978) ...; and Japan Whaling Ass'n v. American Cetacean Society, 478 U.S. 221, 106 S.Ct. 2860, 92 L.Ed.2d 166 (1986)...." Supplemental Brief for Petitioners at 8. These authorities do not support the broad proposition for which they are cited, viz., that the increased use of gasoline by American consumers as a whole constitutes an injury-in-fact to these petitioners' members.

The plaintiffs in SCRAP were able to satisfy the Court that the challenged order would adversely affect recreational resources actively used by their members in the Washington, D.C. area. 412 U.S. at 685, 93 S.Ct. at 2415. Unlike the SCRAP plaintiffs, these petitioners' members have alleged no specific injury uniquely suffered apart from the interest shared by all in reducing our nation's fuel consumption. Thus, they resemble more closely the plaintiffs in Sierra Club v. Morton, 405 U.S. 727, 92 S.Ct. 1361, 31 L.Ed.2d 636 (1972), than the SCRAP plaintiffs. Indeed, SCRAP specifically distinguished Sierra Club on this basis. 412 U.S. at 687, 93 S.Ct. at 2416 ("No such specific injury was alleged in Sierra Club.").

Similarly, the plaintiffs in Duke Power included "40 individuals who live within a close proximity to the planned [nuclear power] facilities." 438 U.S. at 67, 98 S.Ct. at 2416. The Court accepted only two of the district court's extensive findings with respect to injury: "the environmental and aesthetic consequences of the thermal pollution of the two lakes in the vicinity of the disputed power plants.... [a]nd the emission of non-natural radiation into appellees' environment...." 438 U.S. at 73-74, 98 S.Ct. at 2630-31 (emphasis added). Duke Power clearly involved a more immediate and direct injury than the generalized interest in energy conservation asserted by these petitioners.

Finally, petitioners cite American Cetacean for the proposition that "denial of [an] opportunity to watch whales" is sufficient to establish Article III standing. Supplemental Brief for Petitioners at 8. There, the Court indicated that the adverse effect of the challenged action on the whale watching and studying of the plaintiff organizations' members was a sufficient injury-in-fact. American Cetacean did not hold that any member of the public who desired that Congress' policy of whale conservation be carried out could bring suit in federal court. Rather, as the Court's citation to Sierra Club and SCRAP makes clear, petitioners' standing was established by the impact of the challenged actions on the use of specific natural resources by specific members.

At oral argument, petitioners made the further claim that increased gasoline consumption by the nation as a whole will increase the gasoline prices that their members pay. Petitioners have failed to demonstrate adequately that the injury will materialize. First, petitioners failed to show that the increases in credits will increase fuel consumption. We cannot assume this will occur. For example, even if Ford and GM choose to increase their CAFE ratings in model years 1986 through 1988 through such measures as discontinuing their less fuel efficient models (cf. infra at 872), there is no reason to conclude that Americans will respond by consuming less gasoline. Consumers accustomed to buying Cadillacs or Lincolns might decide to keep older cars or shift to foreign cars that consume more gas. Moreover, those who purchase more fuel efficient cars might choose to drive more. Clearly, the effect of the credits on fuel consumption in a particular year is simply speculative.

Similarly, there is no evidence that any increase in demand that might be attributed to the automobiles produced by GM and Ford in the United States will have a measurable impact on gasoline prices. Petroleum prices are determined by global supply and demand. Any increase in demand traceable to the less efficient fleets produced by these two manufacturers would represent so trifling a percentage of the global market that the price at the pump is unlikely to be affected. Cf. Metcalf v. National Petroleum Council, 553 F.2d 176, 186 (D.C.Cir.1977) (appellants failed to specify monetary loss resulting from domination of National Petroleum Council; "[t]he injury needed for standing does not have to be substantial, but it must be at least identifiable...." (emphasis in original)).

Petitioners have the burden of demonstrating a "distinct and palpab