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Sunday, December 12, 2010

Federal Agency Actions Following the Supreme Court’s Climate Change Decision: A Chronology

Robert Meltz
Legislative Attorney/Acting Section Research Manager

On April 2, 2007, the Supreme Court rendered one of its most important environmental decisions of all time. In Massachusetts v. EPA, the Court held that greenhouse gases (GHGs), widely viewed as contributing to climate change, constitute “air pollutants” as that phrase is used in the Clean Air Act (CAA). As a result, said the Court, the U.S. Environmental Protection Agency (EPA) had improperly denied a petition seeking CAA regulation of GHGs from new motor vehicles by saying the agency lacked authority over such emissions.

This report presents a chronology of major federal agency actions taken in the wake of Massachusetts v. EPA. Most of the listed actions trace directly or indirectly back to the decision— EPA’s “endangerment finding” for GHGs from new motor vehicles, the agency’s proposed standards for such vehicles, its interpretation of the phrase “subject to regulation” (the CAA trigger for requiring “best available control technology” in “prevention of significant deterioration” areas), guidance for determining best available control technology, and the “tailoring rule” (limiting the stationary sources that initially will have to install best available control technology and obtain CAA Title V permits). A few agency actions were included solely because of their relevance to climate change and their post-Massachusetts occurrence—for example, EPA’s responses to California’s request for a waiver of CAA preemption allowing that state to set its own limits for GHG emissions from new motor vehicles, and EPA’s monitoring rule for GHG emissions.

More analytical treatment of the government actions in this report may be found in CRS Report RL32764, Climate Change Litigation: A Survey, by Robert Meltz; CRS Report R40984, Legal Consequences of EPA’s Endangerment Finding for New Motor Vehicle Greenhouse Gas Emissions, by Robert Meltz; CRS Report RS22665, The Supreme Court’s Climate Change Decision: Massachusetts v. EPA, by Robert Meltz; CRS Report R40585, Climate Change: Potential Regulation of Stationary Greenhouse Gas Sources Under the Clean Air Act, by Larry Parker and James E. McCarthy; and CRS Report R40506, Cars, Trucks, and Climate: EPA Regulation of Greenhouse Gases from Mobile Sources, by James E. McCarthy.

Date of Report: December 3, 2010
Number of Pages: 10
Order Number: R41103
Price: $19.95

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