Opposition Brief — Massachusetts v. EPA

FILED

(4 MAY 15 2006

OFFICE OF THE CLERK

No. 05-1120 |_ SUPREME COURT, U.S.

Jn the Supreme Court of the Cited States

COMMONWEALTH OF MASSACHUSETTS, ET AL.,

PETITIONERS

v.

ENVIRONMENTAL PROTECTION AGENCY, ET AL.

ON PETITION FOR A WRIT OF CERTIORARI

TO THE UNITED STATES COURT OF APPEALS

FOR THE DISTRICT OF COLUMBIA CIRCUIT

BRIEF FOR THE FEDERAL RESPONDENT

IN OPPOSITION

PAUL D. CLEMENT

Solicitor General

ANN R. KLER Counsel of Record

General Counsel SUE ELLEN WOOLDRIDGE

THOMAS SWEGLE Assistant Attorney General

Attorney “ JON M. LiPSHULTZ

Environmental Protection Attorney

Agency ; ,;

Washington, D.C. 20460 Department oj Justice

Washington, D.C. 20530-0001

(202) 514-2217

QUESTIONS PRESENTED

1. Whether, in this challenge to the denial by the

Environmental Protection Agency of petitioners’ rule-

making petition, petitioners adequately established

standing—.e., that their alleged injuries were caused by

the denial of the rulemaking petition and would be

redressed by a judicial decision in their favor in this

case.

2. Whether the court of appeals correctly deter-

mined that EPA lawfully exercised its discretion in

denying petitioners’ rulemaking petition seeking

regulation of carbon dioxide and other greenhouse gas

emissions from mobile sources (such as cars and light

trucks) under Section 202(a)(1) of the Clean Air Act, 42

U.S.C. 7521(a)(1), where, among other things, EPA

believed pertinent scientific and technological issues

could be better analyzed after the completion of ongoing

studies.

3. Whether EPA correctly determined that the

Clean Air Act does not in any event give it authority to

regulate greenhouse gas emissions for the purpose of

addressing concerns about global climate change.

(I)

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TABLE OF AUTHORITIES

Cases:

Allen v. Wright, 468 U.S. 737 (1984) ......... cee eee eee 15

American Horse Prot. Ass’n v. Lyng, 812 F.2d 1

ED bucdsdansdensadesepdnaséebeatenes 17

ASARCO Ine. v. Kadish, 468 U.S. 737 (1984) .......... 15

Chevron U.S.A. Inc. v. Natural Res. Def. Council,

Eg CE an ae 25

Elk Grove Unified Sch. Dist. v. Newdow, 542 U.S. 1

(2004) ...... ltdiddadxsdedsckiGwahsedenieneneses 1]

Environmental Def. Fund v. EPA, 598 F.2d 62

(D.C. Cir. 1978) .......: Mmekentssnebedebatedens 9

Environmental Def. Fund vy. Thomas, 870 F.2d 892

(2d Cir.), cert. denied, 493 U.S. 991 (1989) .......... 17

Ethyl Corp. v. EPA, 541 F.2d 1 (D.C. Cir.), cert.

denied, 426 U.S. 941 (1976) ............0 0c ee eee 16,21 —

FDA v. Brown & Williamson Tobacco Corp.,

EE -ebkuSevednensesedasksnckdhans 4, 23

General Motors Corp. v. NHTSA, 898 F.2d 165

EE ores sncdnedbaceuneteeedseeseenses 17

Gustafson v. Alloyd Co., 513-U.S. 561 (1995) ........... 23

Her Majesty the Queen in Right of Ont. v. EPA,

912 F.2d 1525 (D.C. Cir. 1990)............... 16, 17, 20

King v. St. Vincent’s Hosp., 502 U.S. 215 (1991) ........ 23

(III)

IV

Cases—Continued: Page

Lujan v. Defenders of Wildlife, 504 U.S. 555 (1992) ..... 11

Lytle v. Household Mfg., Inc., 494 U.S. 545 (1990) ...... 22

McCarthy v. Bronson, 500 U.S. 186 (1991)... 2... eee 23

Midwest Indep. Transmission Sys. Operator, Ine. v.

FERC, 388 F.3d 903 (D.C. Cir. 2004) ...........4.. 17

NRDC v. SEC, 606 F.2d 1031 (D.C. Cir. 1971) ...... 18, 21

NRDC v. Thomas, 885 F.2d 1067 (2d Cir. 1989) ........ 17

National Ass'n of Regulatory Util. Comm’rs v. DOR,

851 F.2d 1424 (D.C. Cir. 1988) ...... cc eee cceceenes 18

National Mining Ass'n v. DOI, 70 F.3d 1345

els 2 Perr 17

New York Pub. Interest Research Group v. Whitman,

SE FBG S06 GS CW. FRR nce ccccvssescccesevss 17

Professional Drivers Council v. Bureau of Motor

Carrier Safety, 706 F.2d 1222 (D.C. Cir. 1983) ...... 21

Sierra Club v. EPA, 292 F.3d 895 (D.C. Cir. 2002) ...... 6

Sierra Club v. Thomas, 828 F.2d 783 (D.C. Cir. 1987) ... 21

Simon v. Eastern Ky. Welfare Rights Org.,

GER UE BIG sescccccusceviscsessusseuanl 11,13

Steel Co. v. Citizens for a Better Env't, 523 U.S. 83

CUBR occ cccsccsesusevcessenevessebes eenaneeee 7

Timpinaro v. SEC, 2 F.3d 453 (D.C. Cir. 1993) ........ 17

Union Elec. Co. v. EPA, 427 U.S. 246 (1976) ........... 19

Vermont Yankee Nuclear Power Corp. v. NRDC,

4B UD. GIDC oc cvcvccccnccviecvéscvconscetnt 21

WWAT, Inc. v. FCC, 656 F.2d 807 (D.C. Cir. 1981) .. 18, 19

Whitman v. American Trucking Ass’ns, 531 US. 457

Case—Continued: Page

Yee v. City of Escondido, 503 U.S. 519 (1992) .......... 22

Constitution and statutes:

ed ood cee oeeceesepaceeves 10

Clean Air Act, 42 U.S.C. 7401 et seq. ............. passim

Fs co coueavasecenees 2

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es Oe cco tceccedsee 2,23

§ 112(a)(1), 42 U.S.C. 7412(a)(1) (1988) ..... 20... 17

§ 112(b)(3), 42 U.S.C. 7412(b)(3) . 0... eee ee eee. 20

§ 112(b)(4), 42 U.S.C. 7412(b)(4) «2.2... eee eee. 20

S BRBa), GB UBC. TEIMa) 2. nce cccccccccccccecs 17

$§ 172 et seqg., 42 U.S.C. 7502 et seq. ............. 23

EEE EE a 2

$§ 202-250, 42 U.S.C. 7521-7590 .................. 2

i a i eee cancede 21

Eh CD cccdcccceuccestecsese 22

Tit. IIT:

ies icin ukbaeeesseceses 3

§ 302(g), 42 U.S.C. 7602(g) 2.0.00... 0... 3, 24, 25

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Tit. V:

VI

Statutes—Continued: - , Page

Energy Policy and Conservation Act, 49 U.S.C. 32901

et seq.:

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In the Supreme Court of the Anited States

No. 05-1120

COMMONWEALTH OF MASSACHUSETTS, ET AL.,

PETITIONERS

v.

ENVIRONMENTAL PROTECTION AGENCY, ET AL.

ON PETITION FOR A WRIT OF CERTIORARI

TO THE UNITED STATES COURT OF APPEALS

FOR THE DISTRICT OF COLUMBIA CIRCUIT

BRIEF FOR THE FEDERAL RESPONDENT

IN OPPOSITION

OPINIONS BELOW

The opinion of the court of appeals (Pet. App. A1-A58)

is reported at 415 F.3d 50. The decision of the Environ-

mental Protection Agency (Pet. App. A59-A97) is published

at 68 Fed. Reg. 52,922.

JURISDICTION

The judgment of the court of appeals was entered on

July 15, 2005. Petitions for rehearing were denied on De-

cember 2, 2005 (Pet. App. A94-A98 ). The petition for a writ

of certiorari was filed on March 2, 2006. The jurisdiction of

this Court is invoked under 28 U.S.C. 1254(1).

(1)

STATEMENT

Petitioners seek review of a decision of the court of ap-

peals upholding the denial by the Environmental Protection

Agency (EPA) of a rulemaking petition seeking regulation

of emissions of carbon dioxide and three other greenhouse

gases from new motor vehicles under the Clean Air Act

(CAA), 42 U.S.C. 7401 et seq. In denying the petition, EPA

first determined that it did not have authority under the

CAA to regulate emissions of greenhouse gases to address

concerns about climate change. See Pet. App. A59-A93.

The Agency further explained that even if it had the requi-

site regulatory authority, it would still deny the rulemaking

petition for a number of other reasons, including its desire

to have the benefit of ongoing scientific and technical stud-

ies before making a regulatory decision of such complexity

and potential effect. /d. at A80-A87. Numerous petitioners

challenged the denial of the rulemaking petition, but the

court of appeals denied their petitions for review. See id. at

A1-A58.

1. Sections 108 and 109 of Title I of the CAA, 42 U.S.C.

7408-7409, authorize EPA to set national ambient air qual-

ity standards (NAAQS) for air pollutants that cause or con-

tribute to air pollution that may reasonably be antic pated

to endanger public health or welfare and that are emitted

by numerous or diverse sources. Section 110 of the CAA,

42 U.S.C. 7410, establishes a federal-state partnership for

meeting NAAQS in local air quality control regions through

state implementation plans.

While most of the provisions in Title { of the CAA focus

on stationary sources of air pollution, Tit‘e LI of the Act

establishes a regulatory framework for federal control of

pollution from motor vehicles and other mobile sources.

See CAA Sections 202-250, 42 U.S.C. 7521-7590. This case

3

specifically involves Section 202(a)(1) of the CAA, 42 U.S.C.

7521(a)(1), which authorizes EPA to “prescribe * * *

standards applicable to the emission of any air pollutant

from any class or classes of new motor vehicles or new mo-

tor vehicle engines, which in [EPA’s] judgment cause, or

contribute to, air pollution which may reasonably be antici-

pated to endanger public health or welfare.”

Section 302 of the Act, 42 U.S.C. 7602, sets forth general

definitions applicable to the CAA as a whole. Section

302(g), 42 U.S.C. 7602(g), defines “air pollutant” as “any air

pollution agent or combination of such agents, including any

physical, chemical, biological, [or] radioactive * * * sub-

stance or matter which is emitted into or otherwise enters

the ambient air[,]” including any precursors to the forma-

tion of such air pollutant. “[E]ffects on welfare” is defined

to include “effects on soils, water, crops, vegetation, man-

made materials, animals, wildlife, weather, visibility, and

climate, and damage to * * * property, and hazards to

transportation, as well as effects on economic values and on

personal comfort and well-being.” 42 U.S.C. 7602(h).

2. On October 20, 1999, the International Center for

Technology Assessment and several other parties filed a

rulemaking petition asking EPA to regulate emissions of

carbon dioxide, methane, nitrous oxide, and

hydrofluorocarbons from new motor vehicles. The petition

alleged that emissions of those “greenhouse gas|es]” from

motor vehicles contributed to global climate change, satis-

fied the criteria for regulation under Section 202(a)(1) of

the Act, 42 U.S.C. 7521(a)(1), and would be feasible for

EPA to regulate. See Pet. App. A59-A63. After soliciting

and considering approximately 50,000 public comments, see

id. at A63, EPA issued a written decision denying the peti-

tion. /d.at A59-A93.

d

EPA first concluded that Congress did not provide it

with authority in the CAA to regulate carbon dioxide and

_ other greenhouse gases to address concerns about global

climate change. Pet. App. A67, A68-A79. EPA explained

that it must be cautious about “using broadly worded statu-

tory authority to regulate in areas raising unusually signifi-

cant economic and political issues when Congress has spe-

cifically addressed those areas in other statutes.” /d. at

A68 (citing FDA v. Brown & Williamson Tobacco Corp.,

529 U.S. 120 (2000)). In that regard, EPA noted that the

only provisions of the Act that sr 2cifically mention carbon

dioxide or “global warming” are non-regulatory in nature,

and pointed out that when Congress elsewhere wanted to

address an analogous type of global environmental is-

sue—stratospheric ozone depletion—it added an entirely

new set of provisions to the CAA specifically tailored to that

problem and its international dimensions. /d. at A70-A72.

EPA further noted that Congress had enacted non-CAA

legislation in recent years specifically directed to climate

change, and had rejected numerous attempts to give EPA

authority to regulate greenhouse gas emissions to address

climate change. /d. at A75. For those and other reasons,

EPA determined that the CAA, read as a whole, did not

provide the Agency with authority to promulgate the type

of regulation sought by petitioners. /d. at A78.

EPA also explained why, even if it had the requisite

CAA regulatory authority, it would deny the rulemaking

petition. Based in large part on its review of a 2001 report

on global climate change by the National Research Council

(NRC), EPA identified numerous areas of scientific uncer-

tainty involving the mechanisms of-climate change, its po-

tential effects on human health and the environment, and

the means by which such issues can most effectively be ad-

dressed. Pet. App. A82-A84. Noting NRC’s conclusion that

5

“(t]he understanding of the relationships between weather/

climate and human health is in its infancy and therefore the

health consequences of climate change are poorly under-

stood,” EPA found that “{s}ubstantial scientific uncertain-

ties limit our ability to assess each of these factors and to

separate out those changes resulting from natural variabil-

ity from those that are directly the result of increases in

anthropogenic |greenhouse gases].” /d. at A84; see id. at

A83 (the “science of climate change is extraordinarily com-

plex and still evolving”). EPA explained that “[{u|ntil more

is understood about the causes, extent and significance of

climate change and the potential options for addressing it,

EPA believes it is inappropriate to regulate [greenhouse

gas] emissions from motor vehicles.” /d. at A&86. EPA

identified a variety of ongoing efforts that were then under-

way to further investigate the areas of scientific and techni-

cal uncertainty, and explained its view that “establishing

[greenhouse gas| emission standards for U.S. motor vehi-

cles at this time would require EPA to make scientific and

technical judgments without the benefit of the studies being

developed to reduce uncertainties and advance technolo-

gies.” Jd. at A85.

EPA also explained that any effort by it to regulate

greenhouse gas emissions from motor vehicles at this time

would necessarily raise other important legal and policy

concerns, such as possible interference with foreign policy

considerations including the United States’ negotiations

with developing nations. Pet. App. A&86. In addition, since

at present “the only practical way to reduce tailpipe emis-

sions of |carbon dioxide] is to improve fuel economy,” id. at

A79, a regulation directed to that end would present prob-

lems of coordination and inconsistency with the statutory

scheme of the Energy Policy and Conservation Act

(EPCA), 49 U.S.C. 32901-32919, which authorizes the De-

6

partment of Transportation (DOT) to set fuel economy

standards. Pet. App. A79-A80, A&86-A87.'

3. Numerous petitions for review of EPA’s denial of

the rulemaking petition were filed in the D.C. Circuit. On

July 15, 2005, the court of appeals decided the consolidated

case in EPA’s favor, finding that the challenges to EPA’s

action should be denied. Pet. App. Al-A58.° Judge

Randolph filed the judgment of the court, but each of the

three judges on the panel filed a separate opinion adopting

a distinct analysis.

a. EPA challenged petitioners’ standing to bring this

case, arguing that petitioners had failed to show causation

(i.e., that their alleged injuries were caused by EPA’s deci-

sion not to regulate emissions of greenhouse gases from

new motor vehicles) and redressability (7.e., that their al-

leged injuries could be redressed by a judicial decision in

their favor in this case). Judge Randolph stated that the

declarations submitted by petitioners “‘support each ele-

ment’ of standing” sufficiently to survive a summary judg-

ment motion. Pet. App. A&8 (quoting Sierra Club v. EPA,

' In EPCA, Congress set the corporate average fuel economy

(CAFE) standard for “passenger automobile[s]|” (a term that includes

a variety of vehicles carrying up to 10 passengers). 49 U.S.C.

32901(a)(16), 32902(b). Congress also provided that any DOT action

increasing (or significantly decreasing) the stringency of the standard

he subject to congressional review and potential disapproval. 49 U.S.C.

32902(c). Moreover, Congress designed EPCA to allow automobile

manufacturers substantial flexibility in meeting CAFE standards

through credit banking and borrowing provisions. 49 U.S.C. 32905.

* Several of the petitions for review attempted to challenge the

memorandum by EPA’s General Counsel that was cited in EPA’s deci-

sion. See Pet. App. A6. Judge Randolph rejected those challenges, on

the ground that the memorandum was not final agency action subject

to judicial review. /bid. Neither Judge Sentelle nor Judge Tatel dis-

sented from that disposition or otherwise discussed it.

7

292 F.3d 895, 899 (D.C. Cir. 2002)). But he observed that

the record also “contains a wealth of * * * ‘other evi-

dence,’ and some of it contradicts petitioners’ claim that

greenhouse gas emissions from new motor vehicles have

caused or will cause a significant change in the global cli-

mate.” /d. at A9. He concluded that, in that unusual situa-

tion, the court should “proceed to the merits with respect to

EPA’s alternative decision not to regulate on the grounds,

among others, that thé effect of greenhouse gases on cli-

mate is unclear and that models used to predict climate

change might not be accurate.” Jbid. See id. at A9-A10;

Steel Co. v. Citizens for a Better Env't, 523 U.S. 83, 97 n.2

(1998) (discussing permissibility of proceeding to the merits

before resolving statutory standing issues).

Judge Sentelle concluded that petitioners did not have

standing. In his view, they had “alleged and shown no:

harm particularized to themselves,” Pet. App. A17, but in-

stead had merely shown that “[e}mission of certain gases

that the EPA is not regulating may cause an increase in the

temperature of the earth,” that “{t]his is harmful to human-

ity at large,” and that “[pletitioners are or represent seg-

ments of humanity at large,” id. at A1l8. In Judge Sentelle’s

view, that “would appear to be neither more nor less than

the sort of general harm eschewed as insufficient to make

out an Article III controversy by the Supreme Court and

lower courts.” /bid. Nonetheless, because his preferred

resolution of the case (dismissal for lack of jurisdiction) was

different from the resolutions urged respectively by Judge

Randolph (denial of the petition for review) and Judge

Tatel (grant of the petition for review) and thus would have

prevented issuance of any judgment commanding a major-

ity of the court, Judge Sentelle accepted as law of the case

the view of Judges Randolph and Tatel that the court had

jurisdiction to issue a judgment and then “join{ed] Judge

8

Randolph in the issuance of a judgment closest to that

which [Judge Sentelle himself] would issue.” /d. at A20.

Judge Tatel, alone of the panel members, concluded that

petitioners had shown that they had standing in this case.

In his view, the declarations submitted by Massachusetts

adequately established that global warming would cost the

State a particularized “loss of land within its sovereign

boundaries” as sea levels rise. Pet. App. A27. He con-

cluded that, with respect to causation, other declarations

adequately established “that global warming is chiefly trig-

gered by human-caused [greenhouse gas] emissions.” /d.

at A28. With respect to redressability, he found that a dec-

laration submitted by petitioners adequately established

that regulating greenhouse gas emissions from motor vehi-

cles in the United States “would . . . delay and moderate

many of the adverse impacts of global warming.” /d. at

A29. He also noted that another declaration asserted that

a decision by EPA to regulate greenhouse gases would lead

to improved technologies, which would in time be required

by other countries around the world. /bid. Finally, he

stated that no factual disputes on those issues had to be

resolved, because EPA did not cite or otherwise advance

any record evidence in support of contrary findings. /d. at

A30.

b. On the merits, Judge Randolph stated that he would

merely “assume arguendo that EPA has statutory author-

ity to regulate greenhouse gases from new motor vehicles,”

Pet. App. A10, but that the petition for review should none-

theless be denied because the Administrator “properly ex-

ercised his discretion * * * in denying the petition for

rulemaking,” id. at Al5. He noted the substantial uncer-

tainty in the “current understanding of how the climate

system varies naturally and reacts to emissions of green-

house gases,” an uncertainty that “is compounded by the

9

possibility for error inherent in the assumptions necessary

to predict future climate change.” /d. at Al2. He also

noted that, because Section 202(a)(1) “directs the Adminis-

trator to regulate emissions that ‘in his judgment’ ‘may

reasonably be anticipated to endanger public health or wel-

fare,” it “gives the Administrator considerable discretion”

to take into account not only “scientific evidence” but also

what may be called “policy judgments.” /d. at Al13. He

concluded that, especially given that the rulemaking peti-

tion required EPA to “resolve issues ‘on the frontiers of

scientific knowledge,’” the “EPA Administrator properly

exercised his discretion under § 202(a)(1) in denying the

petition for rulemaking.” /d. at A15 (quoting Environmen-

tal Def. Fund v. EPA, 598 F.2d 62, 82 (D.C. Cir. 1978)).

As noted above, Judge Sentelle did not address the mer-

its of EPA’s denial of the petition for rulemaking in his

opinion.

Judge Tatel dissented. Pet. App. A21-A58. In his view,

EPA had erred in concluding that it had no statutory au-

- thority to regulate greenhouse gas emissions from motor

vehicles—an issue on which neither of the other panel

members expressed an opinion. /d. at A31-A42. Judge

Tatel also stated that EPA had erred in concluding that,

even if it did have that regulatory authority, it would none-

theless decline to make an “endangerment” finding here.

In his view, Section 202(a)(1) authorizes the EPA Adminis-

trator, in determining whether a pollutant “in his judgment

cause|s], or contribute|s| to, air pollution which may reason-

ably be anticipated to endanger public health or welfare,”

only “to determin|e| whether the statutory standard for

endangerment has been met.” /d. at A46. Moreover, Judge

Tatel concluded that the scientific uncertainties associated

with global warming, see id. at A50-A54, the overlapping

responsibilities of the Department of Transportation in

10

setting fuel economy standards, see id. at A55, and the po-

tential for interference with the United States’ ongoing

negotiations with other nations, see 7d. at A56, did not jus-

tify EPA’s action.

4. The court of appeals denied a petition for rehearing

en bane. See Pet. App. A94-A97. Judge Tatel filed an opin-

ion dissenting from the denial of rehearing en banc, in

which Judge Rogers joined. See id. at A95-A98. Judge

Griffith also would have granted the petition for rehearing

en banc, but he did not join Judge Tatel’s dissent from the

denial of that petition. /d. at A95.

ARGUMENT

Petitioners argue that the Clean Air Act required EPA

to embark on the extraordinarily complex and scientifically

uncertain task of addressing the global issue of greenhouse

gas emissions by regulating mobile sources of such emis-

sions in the United States. Although the court of appeals

did not itself reach a firm conclusion regarding petitioners’

standing, petitioners failed to make the necessary showing

of causation and redressability to satisfy Article III stand-

ing requirements. On the merits, EPA reasonably con-

cluded that regulation of greenhouse gases by means of

vehicle emissions standards is neither authorized by the

Clean Air Act nor an appropriate exercise of agency au-

thority at the present time and on the existing record. The

judgment of the court of appeals upholding that deci-

sion—which is supported by separate opinions of the panel

members rather than a single majority opinion and thus

would provi4e a particularly poor vehicle for review—does

not conflicc with any decision of this Court or any other

court of appeals. Further review is not warranted.

1. Asa threshold matter, petitioners lack standing to

bring their challenge. “In every federal case, the party

11

bringing the suit must establish standing to prosecute the

action.” Elk Grove Unified Sch. Dist. v. Newdow, 542 U.S.

1, 11 (2004). In addition to a showing of “injury in fact,” the

plaintiff must establish causation and redressability. The

plaintiff must show that there is “a causal connection be-

tween the injury and the conduct complained of,” so that

the plaintiff's injury is “fairly . . . trace[able] to the chal-

lenged action of the defendant, and not . . . th{e] result

[of] the independent action of some third party not before

the court.” Lujan v. Defenders of Wildlife, 504 U.S. 555,

560 (1992) (quoting Simon v. Eastern Ky. Welfare Rights

Org., 426 U.S. 26, 41-42 (1976)). The plaintiff must also

show that it is “‘likely,’ as opposed to merely ‘speculative,’

that the injury will be ‘redressed by a favorable decision.’”

Id. at 561 (also quoting Simon).

Petitioners in this case failed to establish either causa-

tion or redressability. As Judge Tatel explained, the rele-

vant particularized injury asserted in the declarations sub-

mitted by petitioners was that of the Commonwealth of

Massachusetts, which asserted that greenhouse gas emis-

sions would lead to global warming, which would cause ris-

ing sea levels, which in turn “would lead both to permanent

loss of coastal land and to more frequent and severe storm

surge flooding events along the coast.” Pet. App. A27 (in-

ternal quotation marks omitted). Thus, to establish causa-

tion and redressability, petitioners had to do more than

show that global warming, generally, would cause the al-

leged injury. Rather, they had to show that the subject of

their rulemaking petition—greenhouse gas emissions from

new motor vehicles in the United States—would, at least to

a material extent, cause them the alleged injury.’ In addi-

* Under Section 202(a(1), EPA may regulate only new motor

vehicles and cannot impose controls on existing vehicles. Therefore,

12

tion, they had to show that a successful resolution of this

case—a decision by EPA to impose emission standards on

such new motor vehicles—would, to a material extent, re-

dress that injury.

The declarations that petitioners submitted are insuffi-

cient to make those showings. Judge Tatel cited, as the

best evidence of causation, £ declaration asserting that

global warming, chiefly triggered by anthropogenic green-

house gas emissions, was increasing the sea level, with “the

U.S. transportation sector (mainly automobiles) . . . re-

sponsible for about 7% of global fossil fuel emissions.” Pet.

App. A28 (citation omitted). Similarly, with respect to

redressability, Judge Tatel cited a declaration asserting

that “[al]chievabie reductions in emissions of [carbon diox-

ide] and other [greenhouse gases] from U.S. motor vehicles

would . . . delay and moderate many of the adverse im-

pacts of global warming.” /d. at A28-A29.

In light of the speculative nature of petitioner’s theories,

petitioners failed to establish that the injuries they allege

from global warming are traceable to greenhouse gas emis-

sions from new vehicles in the United States—rather than

to greenhouse gas emissions from other sources in the

United States, greenhouse gas emissions from vehicles or

other sources elsewhere in the world, or entirely different

factors—and that a decision to require regulation of emis-

sions of greenhouse gases from new motor vehicles in the

United States would redress their injuries. Petitioners

allege only an indirect injury from vehicular emissions of

greenhouse gases in the United States; they assert that

such emissions will cause global warming, which in turn will

cause sea levels to rise, which in turn will, in the case of

petitioners have the burden of showing that regulation of new motor

vehicles would provide redress for their alleged injury.

13

Massachusetts, damage its coastal property. As this Court

has explained, “indirectness of injury, while not necessarily

fatal to standing, may make it substantially more difficult

* * * to establish that * * * the asserted injury was the

consequence of the defendants’ actions, or that prospective

relief will remove the harm.” Simon, 426 U.S. at 44-45 (in-

ternal quotation marks and citation omitted). In this case,

as in Simon, “(s]peculative inferences are necessary to con-

nect [petitioners’} injury to the challenged actions,” id. at

45, and a “federal court, properly cognizant of the Art. ITT

limitation upon its jurisdiction, must require more than

[petitioners] have shown before proceeding to the merits.”

Id. at 46.

Indeed, petitioners’ standing allegations rest on specu-

lation at two levels. First, petitioners’ standing argument

depends on their claim that greenhouse gases emitted by

new motor vehicles in the United States alone are sufficient

to cause, at least in material part, the injuries that they

allege will occur from global warming. Petitioners’ declara-

tions, however, address the alleged causation of global

warming by greenhouse gases emitted from many different

sources and from many different countries throughout the

world. Their declarations do not establish that the subject

matter of this case—emissions of greenhouse gases by new

motor vehicles in the United States—causes or meaning-

fully contributes to their injuries.

Second, petitioners’ standing argument depends on the

proposition that EPA, if it adopted standards to limit emis-

sions of greenhouse gases from new vehicles in the United

States, could limit such emissions sufficiently to have an

appreciable effect on global warming and, ultimately, on the

degree of injury petitioners allegedly would suffer. Petition-

ers’ declarations do not establish that a mere reduction in

greenhouse gas emissions from new vehicles in the United

14

States would be sufficient to eliminate or meaningfully re-

duce the harm that they allege they will suffer from global

warming. Indeed, EPA concluded that it would not “be

either effective or appropriate for EPA to establish [green-

house gas] standards for motor vehicles at this time.” Pet.

App. A82 (emphasis added).

In concluding that petitioners had shown casi: ation and

redressability, Judge Tatel relied principally u.. the state-

ment in one declaration that “[alchievable reductions in

emissions of [carbon dioxide] and other greenhouse gases

from U.S. motor vehicles would . . . delay and moderate

many of the adverse impacts of global warming.” Pet. App.

A28-A29. That conclusory statement was taken from the

declarant’s summary of his findings, but the balance of the

declaration did not address the question of whether, or the

extent to which, reductions in greenhouse gas emissions

from new motor vehicles in this country alone would “delay

and moderate” the injuries alleged by petitioners. To the

contrary, the declarant’s conclusion that EPA regulation of

automobile emissions would redress the alleged harm ap-

pears to be based on his claim that, if EPA acts, then for-

eign governments will eventually take similar steps. See

Pet. C.A. Standing App. 220 (para. 32) (“If the U.S. takes

steps to reduce motor vehicle emissions, other countries are

very likely to take similar actions regarding their own mo-

tor vehicles using technology developed in response to the

U.S. program.”). According to the declarant, “[wl]ith such

efforts, accompanied by progress in limiting other emis-

sions, it would be much more likely that the extent of cli-

mate change could ultimately be limited to levels that would

avoid the most serious impacts of global warming.” /bid.*

* Judge Tatel also relied on another declaration that made essentially

the same point. See Pet. App. A29 (quoting statement in declaration

15

In short, petitioners’ theory is that redress of their alleged

injuries would result only from a chain of causation begin-

ning with EPA regulation, which would cause advances in

technology, which would cause decisions by other countries

similarly to limit vehicle emissions, which would cause an

effect on global climate, and which would finally result in a

redress of petitioners’ alleged injuries. Such a chain of cau-

sation, involving coordinated actions by entirely independ-

ent third-party governments around the world, is far too

speculative to support standing. See ASARCO Inc. v.

Kadish, 490 U.S. 605, 615 (1989) (Opinion of Kennedy, J.)

(plaintiffs could not establish standing because whether

their “claims of economic injury would be redressed by a

favorable decision in this case depends on the unfettered

choices made by independent actors * * * whose exercise

of broad and legitimate discretion the courts cannot pre-

sume either to control or to predict”); Allen v. Wright, 468

U.S. 737, 759 (1984) (“chain of causation” is “far too weak

for the chain as a whole to sustain * * * standing,” where it

depended on actions of “numerous third parties” making

“independent decisions”).

In short, petitioners have failed to make the necessary

showings of causation and redressability. The problem is

not that there is a factual dispute raised by the declarations

submitted by petitioners. Rather, the problem is that peti-

tioners have failed adequately to present proof of causation

and redressability, and therefore that they lack standing to

bring this challenge.

that “establishing emissions standards for pollutants that contribute to

global warming would lead to investment in developing improved

technologies to reduce those emissions from motor vehicles, and * * *

successful technologies would gradually be mandated by other coun-

tries around the world”).

16

2. On the merits, the court of appeals correctly upheld

EPA’s decision. Section 202(a)(1) of the Act, 42 U.S.C.

7521(a)(1), expressly conditions the establishment of motor

vehicle emissions standards on a discretionary exercise of

the Agency’s “judgment” as to whether air pollution related

to motor vehicle emissions “may reasonably be anticipated”

to endanger public health or welfare. Because that provi-

sion expressly invokes the Administrator’s “judgment,” it

provides EPA with substantial discretion in deciding

whether and when an endangerment finding can or should

be made in the first instance. Here, the Agency identified

a variety of sensible and appropriate reasons—including

the complex and highly uncertain nature of the scientific

record and the Agency’s desire to have the benefit of ongo-

ing research—for its conclusion that even if it had authority

to regulate greenhouse gas emissions from motor vehicles,

an endangerment finding would be inappropriate at this

time. That conclusion reflects a reasonable exercise of the

Agency’s discretion.

a. As the full D.C. Circuit explained 30 years ago in

Ethyl Corp. v. EPA, 541 F.2d 1, 20 n.37 (en banc), cert. de-

nied, 426 U.S. 941 (1976), the “express provision for admin-

istrative discretion via the ‘judgment’ phrase [in CAA sec-

tion 202(a)(1)] is necessary” precisely because that section

requires EPA to initiate regulation once it makes a deter-

mination of “endangerment” to health or welfare. 541 F.2d

at 20 n.37. Numerous other decisions stress EPA’s discre-

tion in deciding whether to make similar types of threshold

regulatory determinations under similarly structured pro-

visions of the CAA. See, e.g., Her Majesty the Queen in

Right of Ont. v. EPA, 912 F.2d 1525, 1533-1535 (D.C. Cir.

1990) (EPA has discretion whether and when to make the

threshold finding as to whether or not there is “reason to

believe” that emissions from sources in the United States

17

are causing a health or welfare endangerment in another

country under Section 115(a) of the Act, 42 U.S.C. 7415(a)).”

In particular, courts have recognized that EPA may prop-

erly defer making an endangerment determination while it

waits for additional scientific and technical studies to be

completed. Her Majesty the Queen, 912 F.2d at 1533-1534.

b. More generally, courts have long recognized that

agencies are entitled to particular deference in deciding

whether to grant rulemaking petitions.” As the D.C. Circuit

* See New York Pub. Interest Research Group v. Whitman, 321 F.3d

316, 330-331 (2d Cir. 2003) (EPA has discretion whether or not to make

the threshold “determination” regarding deficiencies in state operating

permit programs under Section 502(i) of the Act, 42 U.S.C. 7661a(i));

NRDC v. Thomas, 885 F 2d 1067, 1073-1075 (2d Cir. 1989) (EPA has

discretion in exercising its “judgment” as to whether emissions of

hazardous air pollutants “may reasonably be anticipated” to result in

certain types of illnesses under then-existing version of CAA Section

112(a)(1), 42 U.S.C. 7412(a)(1) (1988)); Environmental Def. Fund v.

Thomas, 870 F.2d 892, 898-899 (2d Cir.) (EPA has discretion to make

the threshold “judgment” as to when it is “appropriate” to issue revised

NAAQS under Section 109 of the Act, 42 U.S.C. 7409), cert. denied, 493

U.S. 991 (1989).

" See, e.g., Midwest Indep. Transmission Sys. Operator, Inc. v.

FERC, 388 F.3d 903, 910-911 (D.C. Cir. 2004) (“[We will overturn an

agency’s decision not to initiate a rulemaking only for compelling cause,

such as plain error of law or a fundamental change in the factual pre-

mises previously considered by the agency.”) (internal quotation marks

and citation omitted); National Mining Ass'n v. DOI, 70 F.3d 1345,

1352 (D.C. Cir. 1995) (“[A]Jn agency’s refusal to initiate a rulemaking is

evaluated with deference so broad as to make the process akin to non-

reviewability.”) (internal quotation marks and citation omitted);

Timpinarov. SEC, 2 F 3d 453, 461 (D.C. Cir. 1993) (such challenges will

be granted “only in the rarest and most compelling of circumstances”)

(internal quotation marks and citations omitted); General Motors Corp.

v. National Highway Traffic Safety Admin., 898 F.2d 165, 169 (D.C.

Cir. 1990) (judicial review is “especially narrow” in cases that involve

challenges to the denial of a petition for rulemaking); American Horse

18

has stated, “{iJt is only in the rarest and most compelling of

circumstances that this court has acted to overturn an

agency judgment not to institute a rulemaking.” WWHT,

Inc. v. FCC, 656 F.2d 807, 818 (1981). Agencies have lim-

ited resources and therefore must have the latitude to set

priorities among possible initiatives and to decide how any

particular policy objective may best be pursued. See id. at

817 (recognizing that “{ajn agency’s discretionary decision

not to regulate a given activity is inevitably based, in large

measure, on factors not inherently susceptible to judicial

resolution—e.g., internal management considerations as to

budget and personnel; evalnations of its own competence;

weighing of competing policies within a broad statutory

framework.”) (quoting NRDC v. SEC, 606 F.2d 1031, 1046

(D.C. Cir. 1971)). Accordingly, the D.C. Circuit has tradi-

tionally described its role in reviewing denials of rule-

making petitions as “limited to ensuring that the agency

has adequately explained the facts and policy concerns it

relied on, and that the facts have some basis in the record.”

National Ass’n of Regulatory Util. Comm’rs v. DOE, 851

F.2d 1424, 1430 (D.C. Cir. 1988) (internal quotation marks

and citation omitted).

ce. Against that background, the facts and policy con-

cerns articulated by EPA were sufficient to sustain its deci-

sion that a finding of endangerment regarding greenhouse

gas emissions from motor vehicles was not appropriate at

this time. As Judge Randolph explained, EPA properly

relied on an authoritative analysis by the NRC, an entity of

the National Academy of Sciences, and that report sup-

ported the Agency’s view that any decision whether or not

to regulate in this area would be better made after further

Prot. Ass'n v. Lyng, 812 F.2d 1, 4-6 (D.C. Cir. 1987) (denials of rule-

making petitions are entitled to the “high end” of deference).

19

research was conducted into critical areas of current scien-

tific uncertainty. See Pet. App. Al1-A13, A83-A85. In addi-

tion, EPA’s decision properly took into account other legal

and policy implications of any decision to initiate regulatory

action at this time.’

d. Petitioners incorrectly assert (Pet. 14-15) that it was

impermissible for EPA to conclude that an “endangerment”

finding was inappropriate at the present time based on the

existing scientific uncertainty and the other factors men-

tioned by EPA. In essence, petitioners argue that in acting

on a petition to initiate rulemaking under Section 202(a)(1),

EPA must make an express finding that endangerment is

either present or absent, and may deny such a petition only

if it makes the latter finding in definitive fashion. There is

no precedential or statutory support for petitioners’ posi-

tion. As discussed above, cases such as Ethyl and Her Maj-

esty the Queen make clear that EPA has significant discre-

tion in making the judgments related to an endangerment

finding under CAA Section 202(a)(1) and similar provisions.

That discretion is particularly pronounced in cases such as

this, which to a significant degree involve the more prelimi-

nary question of when it is appropriate to make an endan-

germent finding. See, e.g., WWHT, Inc., 656 F.2d at 817."

" See Pet. App. A13-A14 (discussing possible effects on United States

foreign policy, the Agency’s concern about initiating a “piecemeal”

regulatory approach to these issues, and the concern that any effort by

EPA to limit carbon dioxide emissions through the imposition of more

stringent fuel econumy standards would conflict with the Department

of Transportation's regulation of fuel economy under EPCA),.

* Neither Whitman v. American Trucking Ass’ns, 531 U.S. 457

(2001), nor Union Electric Co. v. EPA, 427 U.S. 246 (1976), supports

petitioners’ argument. See Pet. 8, 14. Those cases involved the extent

to which costs can be considered by EPA in setting a NAAQS or ap-

proving a state implementation plan, respectively. This case, by con-

trast, involves the distinct threshold question of what factors EPA may

20

Moreover, such an approach would, in effect, deprive

EPA of its statutory authority to exercise its “judgment” on

the threshold determination of when it is appropriate to

make an endangerment finding. In so doing, it would also

effectively cede control over EPA’s limited resources to

anyone who submits a petition for rulemaking, and it would

illogically force EPA to make regulatory decisions even

when it reasonably viewed existing data as unreliable, un-

certain, or inconclusive.

e. Petitioners are mistaken in suggesting (Pet. 14-16)

that the CAA itself precludes EPA from considering the

state of scientific uncertainty and other relevant factors in

making the threshold determination of whether it is now

appropriate to make an endangerment finding. Section

202(a)(1) simply states that any regulation in this area is

conditioned on an exercise of EPA’s “judgment,” and it

does not in any way cabin the Agency’s discretion—proce-

dural or substantive—to decide how to make that judgment

most effectively.” In the absence of any such statutory con-

straints, EPA has discretion to make the threshold deter-

mination of whether the scientific record is sufficiently well

developed to begin the regulatory process. See Her Maj-

esty the Queen, 912 F.2d at 1533-1535 (upholding EPA’s

permissibly take into account in deciding when and whether to make an

“endangerment” determination, not merely the factors to be consulted

once EPA has decided to make such a determination.

” Nor does Section 202(a)(1) expressly address rulemaking petitions

at all. By contrast, in other parts of the Act, where Congress has

intended to prescribe aspects of the process EPA must follow in re-

sponding to such petitions, it has done so expressly. See, ¢.g.,42 U.S.C.

7412(b\(3) and (4) (specifyiag timing and other requirements for

consideration of petitions to modify the CAA list of hazardous pollut-

ants and agency responses thereto); 42 U.S.C. 7661d(b\(2) (specifying

the process for presentation and consideration of petitions to EPA to

object to state CAA operating permits).

21

discretion to await the development of further information

on potential remedial measures before making an endan-

germent finding under Section 115 of the CAA, 42 U.S.C.

7415, dealing with international air pollution); Professional

Drivers Council v. Bureau of Motor Carrier Safety, 706

F.2d 1216, 1222 & n.19 (D.C. Cir. 1983) (agencies may per-

missibly defer decision whether or not to regulate for a

variety of reasons within their “special expertise,” including

whether “the scientific state of the art [is] such that suffi-

cient data are not yet available on which to premise ade-

quate regulations”) (emphasis omitted) (quoting NRDC v.

SEC, 606 F.2d at 1046)."" EPA’s decision is thus consistent

with the statute, applicable precedent, and with the more

general rule that courts should refrain from imposing rule-

making requirements on agencies that go beyond those im-

posed by Congress. See Vermont Yankee Nuclear Power

Corp. v. NRDC, 435 U.S. 519 (1978).

f. Petitioners correctly point out (Pet. 15) that the D.C.

Circuit’s decision in Ethyl endorsed the notion that EPA’s

broad discretion under Section 202 of the Act could support

a judgment to regulate, even if the record before the

Agency evidences some scientific uncertainty, when the

Agency deems such a course to be appropriate. See Ethyl,

541 F.2d at 27-28. Petitioners err, however, in arguing that

because the Agency may permissibly proceed with regula-

tion even in the face of some uncertainty, it mast do so even

when it has the type of legitimate policy concerns present

” See Sierra Club v. Thomas, 828 F.2d 783, 798 (D.C. Cir. 1987)

(denying an “unreasonable delay” claim and explaining that because

EPA decisions about whether to regulate under the CAA “often

involve| | complex scientific, technological, and policy questions,” the

Agency “must be afforded the amount of time necessary to analyze such

questions so that it can reach considered results in a final rulemaking

that will not be arbitrary and capricious or an abuse of discretion”).

22

here. Instead, EPA has the discretion to make reasonable

determinations in the first instance whether or not to pro-

ceed in the face of scientific uncertainty. The Agency’s con-

clusion that an endangerment determination is not appro-

priate at this time was more than amply explained and sup-

ported by the record, and was properly upheld by the court

of appeals.

3. Petitioners also argue that review is warranted to

consider whether EPA correctly determined that it did not

have authority under Section 202(a) of the Clean Air Act to

regulate greenhouse gas emissions from vehicles for the

purpose of addressing concerns about global climate

change.

a. That i issue was not decided by the court of appeals,

see Pet. App. A10 n.1, and it has never been addressed by

any other court of appeals. This Court rarely addresses a

legal question without the benefit of any prior decisions by

the lower courts. See, e.g., Yee v. City of Escondido, 503

U.S. 519, 538 (1992); Lytle v. Household Mfg., Inc., 494 U.S.

545, 552°'n.3 (1990). No basis supports taking such an ex-

ceptional course here, because the court of appeals cor-

rectly denied the petitions for review on the grounds dis-

cussed above. Moreover, while regulation of greenhouse

gas emissions from new motor vehicles would present the

Agency with issues of quite extraordinary magnitude and

would conflict with a key component of the CAA regulatory

system, EPA’s determination that it had no authority under

the Act to institute such regulation is limited to the specific

context of greenhouse gases and is unlikely to have a signif-

icant effect in other contexts.

b. In any event, EPA’s conclusion that it did not have

regulatory authority to regulate vehicular greenhouse gas

emissions to address the problem of global warming re-

flects a reasonable interpretation-of the CAA and is consis-

23

tent with applicable precedent. As this Court has fre-

quently instructed, statutes must be read as a whole “since

the meaning of statutory language, plain or not, depends on

context.” King v. St. Vincent’s Hosp., 502 U.S. 215, 221

(1991); see, e.g., FDA v. Brown & Williamson Tobacco

Corp., 529 U.S. 120, 132-133 (2000); Gustafson v. Alloyd

Co., 513 U.S. 561, 569, 575 (1995); McCarthy v. Bronson,

500 U.S. 136, 139 (1991). Here, as was true of tobacco regu-

lation in Brown & Williamson, there are persuasive rea-

sons to conclude that the CAA, when read as a whole, does

not confer authority on EPA to regulate emissions of green-

house gases to address concerns about global climate

change.

Nothing in the CAA indicates Congress's intent to regu-

late greenhouse gases for purposes of addressing global

warming, and all indications that are present suggest that

Congress intended a non-regulatory approach to those is-

sues at this time. See Pet. App. A70-A71, A74-A75; see also

id. at A71-A72 (noting Congress’s distinctive approach, not

merely making use of EPA’s ordinary regulatory provi-

sions, to address the global atmospheric issue of strato-

spheric ozone depletion). The NAAQS system—the CAA’s

primary tool for regulating pervasive air pollutants—is

based on state-by-state analyses of compliance with na-

tional standards, and the Act imposes distinct regulatory

regimes on attainment and nonattainment areas. See CAA

Sections 110, 172 et seqg., 42 U.S.C. 7410, 7502 et seg. That

system would serve no logical purpose in regulating carbon

dioxide and other greenhouse gases, concentrations of

which are not generally subject to substantial local or state-

by-state variation but are instead global in nature. Pet.

App. A71-A73. If petitioners were correct, “any [carbon

dioxide] standard that might be established would in effect

be a worldwide ambient air quality standard, not a national

24

standard—the entire world would either be in compliance

or out of compliance,” zd. at A73, thus rendering the impor-

tant statutory distinction between attainment and non-

attainment areas meaningless. /d. at A73-A74. Effectively

increasing fuel economy standards would be the only way

EPA could attempt to limit vehicle emissions of carbon di-

oxide, but such EPA regulation would conflict with the sep-

arate statutory scheme that Congress carefully developed

and expressly crafted to address fuel economy standards,

under which a division of the Department of Transportation

is responsible for such standards. See id. at A79-A80."'

In short, EPA reasonably concluded that the CAA does

not confer authority on EPA to regulate greenhouse gas

emissions to address global climate change. See Pet. App.

A78. Section 202(a)(1) authorizes EPA only to regulate

“any air pollutant,” and “air pollutant” is in turn defined as

“any air pollution agent or combination of such agents, in-

cluding any physical, chemical, biological, radioactive

* * * substance or matter which is emitted into or other-

wise enters the ambient air.” 42 U.S.C. 7602(g¢). Under

that definition, “a substance does not meet the CAA defini-

tion of ‘air pollutant’ simply because it is a ‘physical, chemi-

cal, biological, radioactive * * * substance or matter

which is emitted into or otherwise enters the ambient air.’

It must also be an ‘air pollution agent’” in order to be regu-

lated under Section 202(a)(1). Pet. App. A79 n.3. For the

reasons discussed above, EPA reasonably concluded that

“the term ‘air pollution’ as used in the regulatory provisions

[of the CAA] cannot be interpreted to encompass global

climate change.” /d. at A78. Therefore, carbon dioxide and

'' As the court of appeals noted, the rulemaking petition made “no

suggestion” as to how emissions of the three greenhouse gases other

than carbon dioxide that were the subject of the rulemaking petition

might be reduced from motor vehicles. See Pet. App. Al4.

25

other greenhouse gases “are not ‘agents’ of air pollution

and do not satisfy the CAA Section 302(g) definition of ‘air

pollutant’ for purposes of” the CAA’s regulatory provisions,

including Section 202(a)(1). /bid."

4. Finally, petitioners err in contending (Pet. 22-26)

that further review is warranted because of the asserted

urgency of the environmental issues involved. EPA has

never contested that global climate change is an important

issue worthy of focused attention, both in the United States

and abroad. In fact, the Agency detailed in its decision in

this case a variety of efforts that the federal government is

currently undertaking to “effectively and efficiently ad-

dress the climate change issue over the long term.” Pet.

App. A82; see id. at A82-A93. Those efforts, and others

that could follow as the numerous scientific and factual

questions involved in the issue of global warming are clari-

fied further, are better tailored to address this quintes-

sentially multinational issue than is the ill-suited regulatory

machinery of the CAA, which could attack only a small and

isolated part of it.

'° Petitioners and the dissenting judge below thus err in contending

that EPA has disregarded the Act’s “plain” text. Pet. App. A33; see

Pet. 18. They erroneously assume that the definition of “air pollutant”

necessarily encompasses any “physical, chemical, biological, radioactive

* * * substance or matter which is emitted into or otherwise enters

the ambient air,” see Pet. App. A32 (citing 42 U.S.C. 7602(g), but EPA

has rejected that view, and has instead authoritatively construed the

definitional provision’s reference to “air pollution agent” to have

independent meaning and effect. See id. at A78-A79 & n.3. That

reasonable interpretation of the ambiguous statutory definition is

entitled to deference under Chevron U.S.A. Inc. v. Natural Resources

Defense Council, Inc., 467 U.S. 837 (1984).

26

CONCLUSION

The petition for a writ of certiorari should be denied.

Respectfully submitted. 2

PAUL D. CLEMENT

ANN R. KLEE Solicitor General

General Counsel SUE ELLEN WOOLDRIDGE

THOMAS SWEGLE Assistant Attorney General

Attorney

Environmental Protection JON M. LipsHuLtz

A gency Attorne y

May 2006