Global Warming: What You Need to Know

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Supreme Court Decision on Greenhouse Gas Regulation

On April 2, 2007, the United States Supreme Court ruled that the Clean Air Act gives the U.S. Environmental Protection Agency (EPA) the authority to regulate greenhouse gas emissions. At issue in the case was the EPA’s ongoing refusal to acknowledge greenhouse gases as air pollution.

In the first case on global warming before the Supreme Court, 12 states, three cities and several environmental groups challenged the EPA’s refusal to consider greenhouse gases as pollutants under the Clean Air Act and regulate them accordingly. The majority decision of the court ruled for the plaintiffs, criticizing the EPA’s rationale for its inaction and instructing the EPA to reconsider its position in light of the court’s ruling.

Why this Case is Important

• Affirmation of statutory authority: This case resolved that the EPA cannot continue to claim that it lacks existing statutory authority to regulate greenhouse gas emissions that cause global warming. Section 201(a)(1) of the Clean Air Act states that the EPA administrator "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." In its decision, the court ruled that CO2 and other greenhouse gases are classified as air pollutants.

• Confirmation of global warming impacts on the United States: The states and environmental groups had to prove that they suffered harm in order to be granted “standing,” which proved to be a controversial aspect in the case. In order for a plaintiff to have judicial standing, they must demonstrate that they suffer from actual or imminent injury, that this injury is “fairly traceable” to the actions of the defendant, and that the injury can be redressed or remedied by action taken by the court. The Supreme Court ruled that Massachusetts suffered an individual injury that was both actual and imminent in the form of loss of sovereign territory due to rising sea levels caused by global warming. It also reasoned that the EPA’s decision not to regulate greenhouse gases contributed to the injury, and that a reduction in U.S. emissions would be a substantial step in slowing global warming and consequently slowing sea level rise. The issue of standing resulted in the court reviewing carefully the science behind global warming, and with its decision, the court essentially validated the scientific consensus and need for emissions reductions.

• Global warming pollution will be regulated: The Supreme Court’s decision that the EPA has a statutory duty to regulate greenhouse gas emissions (unless it can be proven that they do not endanger public health or welfare) has implications for the timing of emissions control policies. Since the court’s ruling puts pressure on the next administration to limit greenhouse gas pollution under the Clean Air Act, current Congressional action on this issue may be accelerated at the urging of industry leaders who seek to work with Congress on crafting emissions policies now, instead of waiting for an executive mandate in the future.

• Regulating auto emissions: This decision impacts how emissions from cars and trucks are regulated in several different ways. Most importantly, it affirms EPA authority to regulate greenhouse gas emissions from tailpipes on the national level. It also bolsters California’s landmark law to cut vehicle greenhouse gas emissions 30% by model year 2016, since the state derives its authority from the EPA under the Clean Air Act. Fifteen other states have adopted, or are in the process of adopting, those emissions standards, but they cannot implement their programs until the EPA grants a waiver to California. In its ruling, the Supreme Court rejected the legal excuses the administration had offered for delaying action on that waiver. However, on December 19, 2007, EPA announced it would reject the waiver request, leading to further legal action by California and 16 other states.

Case History and Background

• EPA refuses to regulate greenhouse gas emissions:
  The original rulemaking petition which requested that the EPA set motor vehicle emissions standards was submitted in 1999. The EPA took four years to review the request and then denied the petition in 2003 on two grounds: the Clean Air Act provided the agency no authority to regulate greenhouse gases, and even if it did, the agency wouldn’t regulate greenhouse gas emissions because it preferred voluntary programs and further study.

• The D.C. Circuit lets EPA’s ruling stand:
  On October 23, 2003, the Commonwealth of Massachusetts and 29 other parties challenged EPA’s decision in the Court of Appeals for the D.C. Circuit. On July 15, 2005, a three-judge panel of the D.C. Circuit let EPA’s ruling stand by a 2-1 vote.

• The Supreme Court grants review:
  On March 2, 2006, the Commonwealth of Massachusetts and others filed petition for certiorari (i.e. reexamination) in the Supreme Court. On June 26, 2006, the Supreme Court took the case for argument on merits, and the case was decided in the petitioners’ favor on April 2, 2007.

• The petitioners:
  The Commonwealth of Massachusetts and 11 other states: California, Connecticut, Illinois, Maine, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont, and Washington; three cities and a U.S. Territory: the District of Columbia, New York City, Mayor and City Council of Baltimore, and the American Samoa Government; thirteen environmental groups: Center for Biological Diversity, Center for Food Safety, Conservation Law Foundation, Environmental Advocates, Environmental Defense, Friends of the Earth, Greenpeace, International Center for Technology Assessment, National Environmental Trust, Natural Resources Defense Council, Sierra Club, Union of Concerned Scientists, and U.S. Public Interest Research Group.

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