Justice Scalia, with whom The Chief Justice, Justice Thomas, and Justice Alito join, dissenting.
I join The Chief Justice's opinion in full, and would hold that this Court has no jurisdiction to decide this case because petitioners lack standing. The Court having decided otherwise, it is appropriate for me to note my dissent on the merits.
I
A
The provision of law at the heart of this case is § 202(a)(1) of the Clean Air Act (CAA or Act), which provides that the Administrator of the Environmental Protection Agency (EPA) "shall by regulation prescribe . . . standards applicable to the emission of any air pollutant from any class or classes of new motor vehicles or new motor vehicle engines, which in his judgment cause, or contribute to, air pollution which may reasonably be anticipated to endanger public health or welfare." 42 U.S.C. § 7521(a)(1) (emphasis added). As the Court recognizes, the statute "condition[s] the exercise of EPA's authority on its formation of a 'judgment.'" Ante, at 532, 167 L. Ed. 2d, at 277. There is no dispute that the Administrator has made no such judgment in this case. See ante, at 534, 167 L. Ed. 2d, at 278 ("We need not and do not reach the question whether on remand EPA must make an endangerment finding"); 68 Fed. Reg. 52929 (2003) ("[N]o Administrator has made a finding under any of the CAA's regulatory provisions that CO [ 2 ] meets the applicable statutory criteria for regulation").
The question thus arises: Does anything require the Administrator to make a "judgment" whenever a petition for rulemaking is filed? Without citation of the statute or any other authority, the Court says yes. Why is that so? When [p550] Congress wishes to make private action force an agency's hand, it knows how to do so. See, e.g., Brock v. Pierce County, 476 U.S. 253, 254-255, 106 S. Ct. 1834, 90 L. Ed. 2d 248 (1986) (discussing the Comprehensive Employment and Training Act (CETA), 92 Stat. 1926, 29 U.S.C. § 816(b) (1976 ed., Supp. V), which "provide[d] that the Secretary of Labor 'shall' issue a final determination as to the misuse of CETA funds by a grant recipient within 120 days after receiving a complaint alleging such misuse"). Where does the CAA say that the EPA Administrator is required to come to a decision on this question whenever a rulemaking petition is filed? The Court points to no such provision because none exists.
Instead, the Court invents a multiple-choice question that the EPA Administrator must answer when a petition for rulemaking is filed. The Administrator must exercise his judgment in one of three ways: (a) by concluding that the pollutant does cause, or contribute to, air pollution that endangers public welfare (in which case EPA is required to regulate); (b) by concluding that the pollutant does not cause, or contribute to, air pollution that endangers public welfare (in which case EPA is not required to regulate); or (c) by "provid[ing] some reasonable explanation as to why it cannot or will not exercise its discretion to determine whether" greenhouse gases endanger public welfare, ante, at 533, 167 L. Ed. 2d, at 277 (in which case EPA is not required to regulate).
I am willing to assume, for the sake of argument, that the Administrator's discretion in this regard is not entirely unbounded--that if he has no reasonable basis for deferring judgment he must grasp the nettle at once. The Court, however, with no basis in text or precedent, rejects all of EPA's stated "policy judgments" as not "amount[ing] to a reasoned justification," ante, at 533-534, 167 L. Ed. 2d, at 277, effectively narrowing the universe of potential reasonable bases to a single one: Judgment can be delayed only if the Administrator concludes that "the scientific uncertainty is [too] profound." Ibid. The Administrator is precluded from concluding for other reasons "that it would . . . be better not to regulate [p551] at this time." Ibid. Such other reasons--perfectly valid reasons--were set forth in the Agency's statement.
"We do not believe . . . that it would be either effective or appropriate for EPA to establish [greenhouse gas] standards for motor vehicles at this time. As described in detail below, the President has laid out a comprehensive approach to climate change that calls for near-term voluntary actions and incentives along with programs aimed at reducing scientific uncertainties and encouraging technological development so that the government may effectively and efficiently address the climate change issue over the long term.
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