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Massachusetts v. EPA: Breaking New Ground on Issues Other Than Global Warming

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Northwestern University Law Review

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After the Supreme Court handed down its split 5-4 decision in Massachusetts v. EPA, various media outlets trumpeted the significance of the case. As one example, the Chicago Tribune proclaimed: "EPA must regulate greenhouse gases."' The problem, of course, is that the Court said no such thing. To be sure, the Court determined that greenhouses gases were "air pollutants" within the meaning of the Clean Air Act (CAA). But the Court's opinion did not order the EPA to regulate with respect to climate change. Rather, the ruling remands the case to allow the agency to reconsider its denial of a petition to regulate the emissions of four pollutants associated with climate change from mobile sources under section 202 of the CAA. The ruling, in other words, leaves the EPA free to decide not to regulate, so long as it provides adequate justification for its decision. This means that what the media has touted as the "global warming" case may not actually lead to the regulation of global warming at all under the current CAA. So wherein lies the true significance of the case? We believe that the long-term significance of the case is likely to be the opinion's impact on two doctrinal areas of the law: (1) the standing of states; and (2) the standard of review applied to denials of petitions for rulemaking. First, although we have some questions about the Court's reasoning, we are encouraged to see the beginning of a framework for evaluating state standing based on the interest of the state in the litigation. Second, with respect to judicial review of agency inaction in the rulemaking context, the Court's decision breaks new ground not only by confirming the reviewability of an agency's denial of a rulemaking petition but also by closely scrutinizing the reasons that the EPA offered for its decision to decline to regulate. Note: This Colloquy Essay was part of a Symposium on Ordering State-Federal Relations Through Federal Preemption Doctrine.

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