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United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued January 23, 2003 Decided March 18, 2003

No. 00-1262

SIERRA CLUB AND

NEW YORK PUBLIC INTEREST RESEARCH GROUP,

PETITIONERS

v.

ENVIRONMENTAL PROTECTION AGENCY AND

CHRISTINE TODD WHITMAN, ADMINISTRATOR,

U.S. ENVIRONMENTAL PROTECTION AGENCY,

RESPONDENTS

On Petitioners’ Motion for Attorney’s Fees

David S. Baron argued the cause and filed the briefs for

petitioners.

David J. Kaplan, Attorney, U.S. Department of Justice,

argued the cause for respondents. With him on the brief was

Jan M. Tierney, Attorney, U.S. Environmental Protection

Agency.

 Bills of costs must be filed within 14 days after entry of judgment.

The court looks with disfavor upon motions to file bills of costs out

of time.
2

Before: GINSBURG, Chief Judge, and ROGERS and TATEL,

Circuit Judges.

Opinion for the Court filed by Circuit Judge TATEL.

TATEL, Circuit Judge: The Clean Air Act authorizes an

award of attorney’s fees ‘‘whenever [the court] determines

that such award is appropriate.’’ In this case, organizations

that settled their Clean Air Act suit against the Environmental Protection Agency prior to adjudication on the merits

move for an award of fees. The EPA opposes the motion,

arguing that only parties who obtain court-awarded relief

may recover fees. Applying relevant Supreme Court precedent, we hold that the Clean Air Act, unlike statutes that

authorize fee awards only to ‘‘prevailing part[ies],’’ permits

awards to so-called catalysts—parties who obtain, through

settlement or otherwise, substantial relief prior to adjudication on the merits. Because we find an award of fees

‘‘appropriate’’ under the circumstances of this case, we grant

the motion.

I.

Title V of the 1990 Amendments to the Clean Air Act, 42

U.S.C. §§ 7661–7661f, establishes procedures through which

the Environmental Protection Agency may authorize states

and localities to issue stationary air pollution source operating

permits. See generally Appalachian Power Co. v. EPA, 208

F.3d 1015, 1017 (D.C. Cir. 2000). Governors must submit

proposals for state or locally administered permit programs

‘‘[n]ot later than 3 years after November 15, 1990,’’ and the

EPA must ‘‘approve or disapprove’’ the proposed programs

within one year of receipt. 42 U.S.C. § 7661a(d)(1); see also

40 C.F.R. § 70.2 (specifying that ‘‘State means any nonFederal permitting authority, including any local agency’’).

If a program ‘‘substantially meets the requirements [for

approval], TTT but is not fully approvable,’’ the EPA may

‘‘grant the program interim approval,’’ which ‘‘shall expire TTT

not later than 2 years after such approval, and may not be

renewed.’’ 42 U.S.C. § 7661a(g). If a state fails to meet

Title V deadlines for obtaining program approval, however,
3

the EPA must itself ‘‘promulgate, administer, and enforce a

program TTT for that State.’’ Id. § 7661a(d)(3), (g), (i)(4).

In 1992, the EPA promulgated 40 C.F.R. § 70.4(d)(2),

which provided—in language virtually identical to Title V’s—

that ‘‘[i]nterim approval shall expire on a date set by the

Administrator (but not later than 2 years after such approval), and may not be renewed.’’ Four years later, in 1996, the

EPA issued a rule that (1) appended a second sentence to 40

C.F.R. § 70.4(d)(2) providing that ‘‘[n]otwithstanding the previous sentence, the Administrator may, through rulemaking,

provide for a longer period of time on an individual basis, but

only once per State’’ and (2) extended most existing interim

approvals by ten months. Operating Permits Program Interim Approval Extensions, 61 Fed. Reg. 56,368, 56,368, 56,370

(Oct. 31, 1996). Twice again, in 1997 and 1998, the EPA

extended existing interim approvals. Extension of Operating

Permits Program Interim Approvals, 62 Fed. Reg. 45,732

(Aug. 29, 1997); Extension of Operating Permits Program

Interim Approval Expiration Dates, 63 Fed. Reg. 40,054 (July

27, 1998). Neither rule, however, cited any statutory or

regulatory authority for the blanket extension. In fact, both

rules expressly stated that the EPA was not acting pursuant

to 40 C.F.R. § 70.4(d)(2), though the rules reserved the

agency’s purported authority to do so in the future. Roughly

a week before the 1998 blanket interim approval would have

expired, the EPA issued yet another rule, this time extending

existing interim approvals for more than thirty states until

December 1, 2001. Extension of Operating Permits Program,

Interim Approval Expiration Dates, 65 Fed. Reg. 32,035 (May

22, 2000). Like the previous extension rules, this rule cited

neither statutory nor regulatory authority for the blanket

extension. Unlike the previous rules, however, it not only

failed to expressly reserve the EPA’s authority to offer

additional extensions under 40 C.F.R. § 70.4(d)(2), but also

gave ‘‘notice that no additional extensions of interim approval

deadlines will be granted.’’ Id. at 32,038.

Sierra Club and New York Public Interest Research Group

filed a petition in this court challenging the EPA’s May 22,

2000 rule as contrary to Title V. After Petitioners had filed
4

their opening brief and six days before the EPA’s brief was

due, the parties reached a settlement and filed a joint motion

requesting a stay of proceedings. Under the settlement, the

EPA agreed to (1) grant no further interim approval extensions; (2) remove the language from 40 C.F.R. § 70.4(d)(2)

purportedly authorizing the EPA to extend interim approvals

beyond two years on a case-by-case basis; (3) initiate a

ninety-day formal notice-and-comment process for interested

parties to identify deficiencies in both fully approved and

interim programs; and (4) provide responses to all comments

received through the notice-and-comment process. The settlement agreement provided that if the EPA breached any of

its promises, Petitioners could ask the court to lift the stay

and set a new briefing schedule. The settlement agreement

also obligated the parties to seek joint dismissal if, by December 1, 2001, the EPA had fulfilled its promises. Dismissal,

the agreement stated, would ‘‘provide an opportunity for

Sierra Club to petition [this] Court for attorneys’ fees within

a reasonable period of time, which petition EPA may oppose.’’

In January 2002, after the EPA fulfilled its obligations

under the settlement agreement, this court, at the parties’

request, dismissed the case. Acting pursuant to the settlement agreement and citing CAA section 307(f), 42 U.S.C.

§ 7607(f), Petitioners then filed a motion requesting attorney’s fees. Section 307(f) provides: ‘‘In any judicial proceeding under this section, the court may award costs of litigation

(including reasonable attorney and expert witness fees) whenever it determines that such award is appropriate.’’ Id.

Because the parties have agreed on the amount that the

EPA will pay if this court rules for Petitioners, the only

question before us is whether a fee award is appropriate in

the first place. The EPA argues that section 307(f)’s ‘‘whenever TTT appropriate’’ standard does not authorize fee awards

to parties, such as Petitioners, whose litigation produces no

court-awarded relief. According to Petitioners, their role as a

catalyst in halting the EPA’s practice of serially extending

interim approvals makes a fee award ‘‘appropriate.’’
5

II.

Whether Petitioners’ role as a catalyst permits fee awards

under section 307(f) turns on the meaning of two Supreme

Court decisions. In Ruckelshaus v. Sierra Club, 463 U.S. 680

(1983), the Supreme Court held that section 307(f)’s ‘‘whenever TTT appropriate’’ standard prohibits awards to parties who

lose on the merits. In Buckhannon Board & Care Home,

Inc. v. West Virginia Department of Health & Human

Resources, 532 U.S. 598 (2001), the Court held that a different

statutory standard, one that authorizes fee awards to ‘‘prevailing part[ies],’’ prohibits awards to catalyst parties, defined

as those who ‘‘achieve[ ] the desired result[s] because the

lawsuit[s] brought about TTT voluntary change[s] in the defendant[s’] conduct.’’ Id. at 601. Because Ruckelshaus did not

involve a catalyst party, and because Buckhannon, which did,

concerned a different statute, neither case addresses the

precise issue we face here. Even so, the parties, though they

read Ruckelshaus and Buckhannon quite differently, agree

that the two cases are dispositive, as do we.

Ruckelshaus began when this court found a fee award to be

‘‘appropriate’’ because the parties requesting fees, though

having lost on the merits, had served as ‘‘expert and articulate spokesmen for environmental TTT interests’’ without

whom ‘‘the process of judicial review might have been fatally

skewed.’’ Sierra Club v. Gorsuch, 672 F.2d 33, 41 (D.C. Cir.

1982). The Supreme Court reversed, explaining that ‘‘[i]t is

difficult to draw any meaningful guidance from § 307(f)’s use

of the word ‘appropriate,’ which means only ‘specially suitable: fit, proper.’ ’’ Ruckelshaus, 463 U.S. at 683 (citation

omitted). ‘‘Our basic point of reference,’’ the Court said, ‘‘is

the ‘American Rule,’ ’’ under which parties bear their own

attorney’s fees. Id. at 683–84. The Court explained that

although Congress has often departed from the American

Rule by shifting fees from the ‘‘prevailing,’’ ‘‘substantially

prevailing,’’ or ‘‘successful’’ party to the losing party, the

additional departure of ‘‘shifting fees from the losing party to

the winning party’’ would require ‘‘a clear showing that this

result was intended.’’ Id. at 684–85. Moreover, the Court

explained, because section 307(f) ‘‘affects fee awards against
6

the United States, as well as against private individuals,’’ it

triggers the interpretive canon that ‘‘[w]aivers of immunity

must be construed strictly in favor of the sovereign’’ and ‘‘not

enlarged beyond what the language requires.’’ Id. at 685

(internal quotation marks and citations omitted). Applying

these two interpretive presumptions, the Court concluded

that ‘‘the term ‘appropriate’ modifies but does not completely

reject the traditional rule that a fee claimant must ‘prevail’

before it may recover attorney’s fees.’’ Id. at 686.

The Court found support for this conclusion in its analysis

of the statute’s legislative history. The Court began by

quoting from a 1977 House Report stating that, ‘‘[i]n the case

of the section 307 judicial review litigation, the purposes of

the authority to award fees are not only to discourage frivolous litigation, but also to encourage litigation which will

assure proper implementation and administration of the act

or otherwise serve the public interest.’’ Id. at 687 (quoting

H.R. REP. NO. 95–294, at 337 (1977)). The Report goes on to

explain, in language italicized by the Court, that ‘‘[t]he committee did not intend that the court’s discretion to award fees

under this provision should be restricted to cases in which

the party seeking fees was the ‘prevailing party.’ ’’ Id.

Seeking to ‘‘determin[e] the meaning of [Congress’s] rejection

of the ‘prevailing party standard,’ ’’ the Court then surveyed

lower court decisions that had applied the ‘‘prevailing party’’

standard ‘‘in a variety of rather narrow ways,’’ concluding

that ‘‘[s]ection 307(f) was meant to expand the class of parties

eligible for fee awards from prevailing parties to partially

prevailing parties—parties achieving some success, even if

not major success.’’ Id. at 687–88 (emphases in original).

The Court also quoted from the 1970 Senate Report on

CAA section 304(d), upon which section 307(f) was modeled,

noting that ‘‘[b]ecause TTT §§ 304(d) and 307(f) have similar

meanings, the history of § 304 is relevant to a construction of

§ 307(f).’’ Id. at 692 n.13. The quoted Senate Report explains that ‘‘[t]he Courts should recognize that in bringing

legitimate actions under this section citizens would be performing a public service and in such instances the courts

should award costs of litigation to such party.’’ Id. at 686 n.8
7

(quoting S. REP. NO. 91–1196, at 38 (1970)) (emphasis in

original). The Report then explains that fee awards ‘‘should

extend to plaintiffs in actions which result in successful

abatement but do not reach a verdict. For instance, if as a

result of a citizen proceeding and before a verdict is issued, a

defendant abated a violation, the court may award litigation

expenses borne by the plaintiffs in prosecuting such actions.’’

Id. Analyzing the Senate Report, the Court concluded in

footnote eight—a passage central to our view of the instant

case—that

Congress found it necessary to explicitly state that

the term appropriate ‘‘extended’’ to suits that forced

defendants to abandon illegal conduct, although

without a formal court order; this was no doubt

viewed as a somewhat expansive innovation, since,

under then-controlling law, some courts awarded

fees only to parties formally prevailing in court. We

are unpersuaded by the argument that this same

Congress was so sure that ‘‘appropriate’’ also would

extend to the far more novel, costly, and intuitively

unsatisfying result of awarding fees to unsuccessful

parties that it did not bother to mention the fact. If

Congress had intended the far-reaching result urged

by respondents, it plainly would have said so, as is

demonstrated by Congress’ careful statement that a

less sweeping innovation was adopted.

Id. (internal citation omitted) (emphases in original).

Buckhannon involved a motion for fees under the Fair

Housing Amendments Act and the Americans with Disabilities Act, both of which authorize courts to grant ‘‘the prevailing party TTT a reasonable attorney’s fee.’’ 42 U.S.C.

§§ 3613(c)(2), 12205. The plaintiff brought a preemption

challenge to a state law, but the action became moot after the

state legislature repealed the allegedly preempted law. Even

though the court never ruled on the merits, the plaintiff

sought an award of attorney’s fees, arguing that its suit was

the catalyst for the repeal.

The Supreme Court began its analysis by observing that

‘‘the term ‘prevailing party’ ’’ is ‘‘a legal term of art.’’ Buck-
8

hannon, 532 U.S. at 603. Quoting from Black’s Law Dictionary, the Court explained that ‘‘prevailing party’’ means ‘‘[a]

party in whose favor a judgment is rendered.’’ Id. Surveying its own precedents involving ‘‘prevailing party’’ feeshifting statutes, the Court observed that it had never approved an award of attorney’s fees without some degree of

formal success, concluding:

A defendant’s voluntary change in conduct, although

perhaps accomplishing what the plaintiff sought to

achieve by the lawsuit, lacks the necessary judicial

imprimatur on the change. Our precedents thus

counsel against holding that the term ‘‘prevailing

party’’ authorizes an award of attorney’s fees without a corresponding alteration in the legal relationship of the parties.

Id. at 605 (emphasis in original). Turning to legislative

history, the Court found it ‘‘at best ambiguous as to the

availability of the ‘catalyst theory’ for awarding attorney’s

fees.’’ Id. at 608. Although the Court also briefly discussed

the parties’ various policy arguments, it concluded that,

‘‘[g]iven the clear meaning of ‘prevailing party’ in the feeshifting statutes, we need not determine which way these

various policy arguments cut.’’ Id. at 610. At no point in the

opinion did the Court discuss Ruckelshaus, much less cite it.

It is on the field of Ruckelshaus and Buckhannon that the

parties in this case do battle. According to the EPA, section

307(f)’s plain language and legislative history, interpreted in

light of the canons of construction employed in Ruckelshaus,

require that, to be eligible for a fee award, a party must have

received some form of court-awarded relief. Ruckelshaus’s

footnote eight discussion of the catalyst theory, the EPA

insists, is dictum. The EPA also contends that because

Ruckelshaus says that section 307(f) applies only to fully and

‘‘partially prevailing parties,’’ 463 U.S. at 688, Buckhannon’s

rejection of the catalyst theory for ‘‘prevailing party’’ statutes

applies to section 307(f) as well. Petitioners have a very

different view of these two cases. They argue that Ruckelshaus’s footnote eight interpretation of section 307(f) controls.
9

Buckhannon, they insist, applies only to ‘‘prevailing party’’

fee-shifting provisions.

Were we operating on a clean slate concerning section

307(f)’s meaning, we would accept the EPA’s invitation to

apply standard tools of statutory construction, including

Ruckelshaus’s presumptions against inferring departures

from the American Rule and waivers of sovereign immunity.

Our slate, however, is far from clean, for in resolving the

issue before it in Ruckelshaus, the Supreme Court engaged in

an analysis of section 307(f) and its legislative history that

determines the outcome of the catalyst issue we face here.

Specifically, Ruckelshaus interprets the 1970 Senate Report

as demonstrating that Congress did in fact authorize fee

awards under section 307(f) for ‘‘suits that forced defendants

to abandon illegal conduct, although without a formal court

order.’’ 463 U.S. at 686 n.8. The Court explained that the

‘‘less sweeping innovation’’ (recovery without formal court

order) ‘‘was adopted,’’ while the more ‘‘far-reaching result’’

(recovery by parties losing on the merits) was not. Id.

(emphases in original). The EPA resists this interpretation,

but neither in its brief nor at oral argument—where we spent

considerable time on the topic—was it able to offer any

interpretation of the ‘‘less sweeping innovation’’ that Congress adopted other than the catalyst theory. Id.

At bottom, the EPA’s only real argument against treating

footnote eight as controlling authority is to dismiss it as

dictum. For this ‘‘inferior Court[ ],’’ U.S. CONST. art. III, § 1,

cl. 1, however, that argument carries no weight since ‘‘carefully considered language of the Supreme Court, even if technically dictum, generally must be treated as authoritative.’’

United States v. Oakar, 111 F.3d 146, 153 (D.C. Cir. 1997)

(internal quotation marks and citation omitted); see also

Bangor Hydro–Elec. Co. v. FERC, 78 F.3d 659, 662 (D.C. Cir.

1996) (‘‘It may be dicta, but Supreme Court dicta tends to

have somewhat greater force—particularly when expressed

so unequivocally.’’).

Moreover, we are not at all certain that footnote eight is

dictum. The footnote’s logic is this: (1) We know Congress
10

authorized catalyst fee recoveries because it said so; therefore (2) we assume Congress rejected losing party recoveries

because it remained silent on the issue. To reject the validity

of the first proposition—as the EPA urges—would pull the

rug from under footnote eight. To be sure, footnote eight is

only one among several justifications that Ruckelshaus gives

for its ultimate holding, but we ‘‘cannot ignore the unmistakable import of [a Supreme Court decision’s] analysis.’’ Oakar, 111 F.3d at 153.

Our understanding of Ruckelshaus also comports with the

Supreme Court’s conclusion, this time in true dictum, that

nearly-identical ‘‘whenever TTT appropriate’’ language in the

pre–1987 Clean Water Act authorizes fee awards in cases

where the plaintiff obtains no court-awarded relief. In

Gwaltney of Smithfield, Ltd. v. Chesapeake Bay Foundation,

Inc., 484 U.S. 49 (1987), the Court held that citizens may sue

under the Clean Water Act only for present, not past, statutory violations. Discussing the possibility that statutory violators could strategically moot enforcement actions by complying with the statute after the actions had been filed, the

Court observed not only that mootness doctrine provides

plaintiffs with certain protections against game-playing violators, but also that

Under the Act, plaintiffs are TTT protected from TTT

suddenly repentant defendant[s] by the authority of

TTT district courts to award litigation costs ‘‘whenever the[y] TTT determine[ ] such award[s] [are] appropriate.’’ 33 U.S.C. § 1365(d). The legislative history of this provision states explicitly that the award of

costs ‘‘should extend to plaintiffs in actions which

result in successful abatement but do not reach a

verdict. For instance, if as a result of a citizen

proceeding and before a verdict is issued, a defendant abated a violation, the court may award litigation expenses borne by the plaintiffs in prosecuting

such actions.’’ S. REP. NO. 92–414, p. 81 (1971), 2

Leg. Hist. 1499.
11

Id. at 67 n.6; see also Save Our Cumberland Mountains, Inc.

v. Hodel, 826 F.2d 43, 51 (D.C. Cir. 1987) (reviewing the

district court’s award of attorney’s fees under another ‘‘whenever TTT appropriate’’ fee-shifting provision and concluding

that ‘‘as the decisions under other fee statutes indicate, to

permit a fee award a party’s litigation efforts need not be the

demonstrably exclusive cause of the relief it sought; rather,

the party may receive an award for time spent on activities

that served as a ‘catalyst’ or contributing factor to that

result’’).

Nothing in Buckhannon alters our conclusion that Ruckelshaus’s footnote eight controls the issue now before us.

Although Buckhannon rejected the catalyst theory, the statute at issue there authorizes fee awards only to ‘‘prevailing

part[ies].’’ By comparison, Ruckelshaus’s footnote eight

analysis directly applies to the issue we face here, as it

interprets section 307(f) to authorize fee awards for ‘‘suits

that forced defendants to abandon illegal conduct, although

without a formal court order.’’ 463 U.S. at 686 n.8.

The most one can say of Buckhannon is that it impliedly

casts doubt on footnote eight. The EPA takes just this

position. Reading Buckhannon’s conclusion that ‘‘prevailing’’

means being ‘‘awarded some relief by the court,’’ 532 U.S. at

603, in light of Ruckelshaus’s statement that ‘‘[s]ection 307(f)

was meant to expand the class of parties eligible for fee

awards from prevailing parties to partially prevailing parties,’’

463 U.S. at 688 (emphasis omitted), the EPA argues that

section 307(f) requires some court-awarded relief. Even setting aside footnote eight, however, we think this inference

quite dubious. The fact that the Supreme Court held in the

context of a fully adjudicated claim that the ‘‘whenever TTT

appropriate’’ standard expands the class of eligible parties to

those who partially prevail on the merits does not address the

status of parties who obtain significant success without adjudication. Even were we to accept the EPA’s interpretation of

‘‘partially prevailing parties,’’ the passage from Ruckelshaus

that the EPA relies on is entirely consistent with the possibility that section 307(f) expands the class from prevailing

parties to ‘‘partially prevailing parties’’ and to parties achiev-
12

ing no formal court-awarded success (a possibility footnote

eight later confirms). Moreover, because the Supreme Court

has warned against ‘‘dissect[ing] the sentences of the United

States Reports as though they were the United States Code,’’

St. Mary’s Honor Ctr. v. Hicks, 509 U.S. 502, 515 (1993), we

think it inappropriate to read a ‘‘prevailing party’’ requirement into section 307(f) just because the Ruckelshaus Court,

not Congress, used that term.

In the end, we need not decide whether Buckhannon—

which never so much as mentions Ruckelshaus—impliedly

overrules footnote eight, for Buckhannon’s failure to do so

expressly is dispositive. If ‘‘a precedent of [the Supreme

Court] has direct application in a case, yet appears to rest on

reasons rejected in some other line of decisions, the Court of

Appeals should follow the case which directly controls, leaving

to [the Supreme] Court the prerogative of overruling its own

decisions.’’ Rodriguez de Quijas v. Shearson/Am. Express,

Inc., 490 U.S. 477, 484 (1989). Here, the case that ‘‘directly

controls’’ is Ruckelshaus. Whether Ruckelshaus ‘‘rest[s] on

reasons rejected’’ by Buckhannon is a matter for the Supreme Court, not us.

Our two sister circuits to have addressed the relationship

between Ruckelshaus and Buckhannon have reached the

same conclusion. In Loggerhead Turtle v. County Council,

307 F.3d 1318 (11th Cir. 2002), the Eleventh Circuit relied on

Ruckelshaus for the proposition that catalyst recoveries are

permitted by ‘‘whenever TTT appropriate’’ statutes and distinguished Buckhannon as applying only to ‘‘prevailing party’’

statutes, specifically noting that ‘‘Buckhannon makes no reference whatsoever to Ruckelshaus or to the ‘whenever TTT

appropriate’ class of fee-shifting statutes.’’ Id. at 1326. In

Center for Biological Diversity v. Norton, 262 F.3d 1077, 1080

n.2 (10th Cir. 2001), although the parties did not raise the

issue, the Tenth Circuit distinguished Buckhannon as applying only to ‘‘prevailing party’’ statutes.

The EPA’s two remaining arguments require little discussion. The agency claims that allowing catalyst recoveries

under section 307(f) will ‘‘create an unnecessary patchwork
13

among fee-shifting statutes,’’ since Buckhannon prohibits

such recoveries under the ‘‘prevailing party’’ standard. Respondents’ Br. at 13. The simple and dispositive answer to

this argument is Ruckelshaus, which tells us that Congress

enacted section 307(f)’s ‘‘whenever TTT appropriate’’ language

for two reasons: to ‘‘reject[ ] TTT the ‘prevailing party’ standard,’’ 463 U.S. at 687, and to authorize fee awards to parties

‘‘that forced defendants to abandon illegal conduct, although

without a formal court order,’’ id. at 686 n.8. It was thus

Congress that created the ‘‘patchwork.’’

The EPA’s other argument suffers essentially the same

defect. The agency claims that the catalyst theory would

‘‘embroil courts in a second major litigation’’ over whether

plaintiffs caused defendants’ changes in conduct. Respondents’ Br. at 14. It is true that Buckhannon notes that one

policy argument against the catalyst theory is that it might

‘‘spawn[ ] a second litigation of significant dimension.’’ 532

U.S. at 609 (internal quotation marks and citation omitted).

Yet in the very next paragraph, Buckhannon points out that,

in light of clearly expressed Congressional intent, ‘‘we need

not determine which way these various policy arguments cut.’’

Id. at 610. The same is true here. Ruckelshaus establishes

that Congress, by enacting section 307(f), intended for courts

to decide when fee awards, even in the catalyst context, are

‘‘appropriate.’’

III.

Having held that the ‘‘whenever TTT appropriate’’ standard

authorizes recovery under a catalyst theory, we turn to the

question of whether such an award is ‘‘appropriate’’ in this

case. On this issue, Buckhannon provides useful guidance.

Though the Court split five to four on the propriety of

catalyst recovery under the ‘‘prevailing party’’ standard, all

nine Justices agreed, albeit in dictum, on the correct standard for whether a lawsuit qualifies as a catalyst. In a

passage arguing that the majority should have given greater

weight to lower court decisions approving catalyst recoveries,
14

the dissent synthesized decisions that had articulated the

standard:

The array of federal court decisions applying the

catalyst rule suggested three conditions necessary to

a party’s qualification as ‘‘prevailing’’ short of a

favorable final judgment or consent decree. A plaintiff first had to show that the defendant provided

‘‘some of the benefit sought’’ by the lawsuit. Under

most Circuits’ precedents, a plaintiff had to demonstrate as well that the suit stated a genuine claim,

i.e., one that was at least ‘‘colorable,’’ not ‘‘frivolous,

unreasonable, or groundless.’’ Plaintiff finally had

to establish that her suit was a ‘‘substantial’’ or

‘‘significant’’ cause of defendant’s action providing

relief. In some Circuits, to make this causation

showing, plaintiff had to satisfy the trial court that

the suit achieved results ‘‘by threat of victory,’’ not

‘‘by dint of nuisance and threat of expense.’’ One

who crossed these three thresholds would be recognized as a ‘‘prevailing party’’ to whom the district

court, ‘‘in its discretion,’’ could award attorney’s fees.

Id. at 627–28 (Ginsburg, J., dissenting) (citations omitted).

Not only did the majority express no disagreement with this

statement of the law, but, citing the dissent, it said that it did

‘‘not doubt the ability of district courts to perform the nuanced ‘three thresholds’ test required by the ‘catalyst theory’—whether the claim was colorable rather than groundless;

whether the lawsuit was a substantial rather than an insubstantial cause of the defendant’s change in conduct; whether

the defendant’s change in conduct was motivated by the

plaintiff’s threat of victory rather than threat of expense.’’

Id. at 610 (emphasis added). Although the majority summarized the three thresholds somewhat differently—failing to

mention the ‘‘some of the benefit sought’’ element and treating ‘‘causation’’ and ‘‘threat of victory rather than threat of

expense’’ as separate elements rather than two aspects of the

same element—nothing suggests that the majority disagreed
15

with the dissent’s position that only a plaintiff achieving

‘‘some of the benefit sought’’ is entitled to fees.

Judged against this so-called three thresholds test, Petitioners’ fee motion is easily resolved. Nowhere does the

EPA suggest that Petitioners’ motion fails to satisfy the

second and third thresholds, and for good reason: Petitioners’ claim was obviously colorable and their suit quite clearly

caused the EPA to accept the settlement’s terms. Cf. Save

Our Cumberland Mountains, 826 F.2d at 51 (‘‘[T]he temporal

sequence of plaintiff’s litigation followed by defendant’s remedial activity is strong evidence of a causal relationship.’’).

Thus, we need only consider the first threshold: Did the

settlement provide Petitioners ‘‘some of the benefit sought’’?

Buckhannon, 532 U.S. at 627 (Ginsburg, J., dissenting) (internal quotation marks and citation omitted).

Answering no, the EPA points out that the settlement

agreement did not require it to withdraw the May 22, 2000

rule, but instead allowed the interim approvals to lapse in

December 2001, just as the rule provided. Although this is

true, it establishes only that Petitioners failed to achieve all

the relief sought, not that they achieved none. By arguing

that Title V expressly forbade interim approval extensions

lasting more than two years, Petitioners necessarily sought

more than just invalidation of the EPA’s specific rule. A

court order invalidating the EPA’s May 22 rule based on

Petitioners’ interpretation of Title V would also—whether

expressly or impliedly—have invalidated any regulation or

other rule permitting extensions lasting more than two years.

Thus, since the settlement agreement (1) prohibited the EPA

from granting additional interim approvals past December

2001 and (2) required the EPA to amend 40 C.F.R.

§ 70.4(d)(2), Petitioners unquestionably achieved some of the

relief they sought.

The EPA’s arguments to the contrary are unpersuasive.

The agency contends that the settlement agreement’s prohibition against further interim approval extensions was redundant because the May 22 rule gave notice that the EPA would

offer no further interim approvals. As the record demonstrates, however, the EPA’s promise was not binding. For

example, in 1995 the agency granted Title V interim approval

extensions in Delaware and Wisconsin, subject to the caveat
16

that the extensions would ‘‘not be renewed.’’ Title V Clean

Air Act Final Interim Approval of Operating Permits Program; State of Delaware, 60 Fed. Reg. 62,032, 62,033 (Dec. 4,

1995); Clean Air Act Final Interim Approval of the Operating

Permits Program; Wisconsin, 60 Fed. Reg. 12,128, 12,136

(Mar. 6, 1995). Yet the 1997, 1998, and 2000 blanket extensions did just that. In contrast, the settlement agreement,

like any relief that this court might have granted on the

merits, bound the EPA.

Finally, the EPA argues that requiring it to amend 40

C.F.R. § 70.4(d)(2) does not constitute relief that Petitioners

sought because the regulation ‘‘was not the basis for the May

22, 2000 extension challenged in this case.’’ Respondents’ Br.

at 5 n.2; see also id. at 15. Not so. The EPA could have

used the regulation, if left unchanged, to authorize further

interim approval extensions, thereby frustrating Petitioners’

basic goal of ending the agency’s serial interim approval

extensions.

IV.

Because we hold that CAA section 307(f) authorizes awards

of attorney’s fees to catalyst parties, and finding an award

‘‘appropriate’’ under the circumstances of this case, we grant

Petitioners’ motion.

So ordered.