Following the Supreme Court’s decision in Massachusetts v. EPA, 549 U.S. 497 (2007)—which clarified that greenhouse gases are an “air pollutant” subject to regulation under the Clean Air Act (CAA)—the Environmental Protection Agency promulgated a series of greenhouse gas-related rules.
Petitioners, various states and industry groups, challenge all these rules, arguing that they are based on improper constructions of the CAA and are otherwise arbitrary and capricious. But for the reasons set forth below, we conclude: 1) the Endangerment Finding and Tailpipe Rule are neither arbitrary nor capricious; 2) EPA’s interpretation of the governing CAA provisions is unambiguously correct; and 3) no petitioner has standing to challenge the Timing and Tailoring Rules. We thus dismiss for lack of jurisdiction all petitions for review of the Timing and Tailoring Rules, and deny the remainder of the petitions. (emphasis added)
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