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Massachusetts v. Environmental Protection Agency

Massachusetts v. Environmental Protection Agency
Supreme Court of the United States
Argued November 29, 2006
Decided April 2, 2007
Full case name: Massachusetts, et al., Petitioners v. Environmental Protection Agency, et al.
Docket #: 05-1120
Citations:549 U.S. 1438; 127 S. Ct. 1438
Prior history:On writ of certiorari to the United States Court of Appeals for the District of Columbia Circuit
Greenhouse gases are air pollutants, and the EPA may regulate their emission
Court membership
Chief Justice: John Glover Roberts, Jr.
Associate Justices: John Paul Stevens, Antonin Scalia, Anthony Kennedy, David Souter, Clarence Thomas, Ruth Bader Ginsburg, Stephen Breyer, Samuel Alito
Case opinions
Majority by: Stevens
Joined by: Kennedy, Souter, Ginsburg, Breyer
Dissent by: Roberts
Joined by: Scalia, Thomas, Alito
Dissent by: Scalia
Joined by: Roberts, Thomas, Alito
Laws applied
Clean Air Act

Massachusetts v. Environmental Protection Agency, 549 U.S. 1438 (2007),[1] is a U.S. Supreme Court case decided 5-4 on April 2, 2007 in which twelve states and several cities of the United States brought suit against the United States Environmental Protection Agency (EPA) to force that federal agency to regulate carbon dioxide and other greenhouse gases as pollutants.


Case background

The Administrator of the Environmental Protection Agency determined in 2003, first, that the EPA lacked authority under the Clean Air Act to regulate carbon dioxide and other greenhouse gases (GHGs), second, that even if the EPA did have such authority the EPA declined to regulate carbon dioxide and other GHGs.

The petitioners were the states of California, Connecticut, Illinois, Maine, Massachusetts, New Jersey, New Mexico, New York, Oregon, Rhode Island, Vermont and Washington, the cities of New York, Baltimore and Washington, D.C., the territory of American Samoa, and the organizations 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.

Respondents were the Environmental Protection Agency, the Alliance of Automobile Manufacturers, National Automobile Dealers Association, Engine Manufacturers Association, Truck Manufacturers Association, CO2 Litigation Group, Utility Air Regulatory Group, and the states of Michigan, Alaska, Idaho, Kansas, Nebraska, North Dakota, Ohio, South Dakota, Texas, and Utah.

Questions presented

Section 202(a)(1) of the Clean Air Act, 42 U.S.C. § 7521(a)(1), requires the administrator of the Environmental Protection Agency ("EPA") to set emission standards for "any air pollutant" from motor vehicles or motor vehicle engines "which in his judgment cause[s], or contribute[s] to, air pollution which may reasonably be anticipated to endanger public health or welfare."

The questions presented were:

  1. Whether the plaintiffs had standing to bring the case to court.
  2. Whether the EPA Administrator has authority to regulate carbon dioxide and other air pollutants associated with climate change under section 202(a)(1).
  3. Whether the EPA Administrator may decline to issue emission standards for motor vehicles based on policy considerations not enumerated in section 202(a)(1).


The U.S. Supreme Court has discretion whether to consider an appeal of most types of cases appealed to it, including cases of this type. On June 26, 2006, the Supreme Court granted a writ of certiorari to award an appeal.[2] The time from granting of the certiorari to oral argument in this case was unusually swift.

Because so few cases are granted an appeal, this tends to indicate unusual interest in the case by the Supreme Court, particularly where an issue has not previously been a persistent topic of disagreement among the lower Federal courts. (A Court tradition, known as the rule of four, says that at least 4 of the Court's 9 Justices must vote in favor of granting certiorari.)

The U.S. Court of Appeals for the District of Columbia Circuit decided on September 13, 2005, to uphold the decision of EPA.[3] However, the reasoning among the appellate judges for coming to the majority conclusion was sharply at odds.

The judges in the lower court explained their reasoning extensively. Id. A review of the lower court decision may contain a preview of the material and arguments that the Supreme Court will draw from in deciding the case.

The lower court was sharply divided on whether the petitioners had 'standing' — a personalized injury creating a right to use the courts (as opposed to the Congress) to obtain government action. One of the three judges found no standing while a second of three postponed a factual decision for any later trial. Despite having granted certiorari, the Supreme Court could have revisited that question in order to dodge a difficult decision and dismiss for lack of standing. Yet, once certiorari has been granted, such a reversal is rare.

Although the Supreme Court may decide cases on unexpected grounds, the lower court's decision appears to raise two main legal questions. The Supreme Court's decision turned on narrow legal questions such as the correct interpretation of the Clean Air Act. The two main issues appeared to be:

(a) whether carbon dioxide is an air pollutant causing air pollution — not in the sense of scientific or factual truth, but in terms of what the Clean Air Act actually says. The Petitioners assert that the CAA defines an air pollutant such that the courts must apply the statutory definition, regardless of anyone's personal views of what is air pollution or not. If carbon dioxide is not an air pollutant causing air pollution, then the EPA has no authority under the Clean Air Act to regulate carbon dioxide emissions.

(b) However, the statutory definition appears to be very broad. The Petitioners argue that the definition in the CAA is so broad that carbon dioxide must be counted as air pollution. This argument said that the question is controlled by the words of the statute, so that factual debate becomes immaterial. An air pollutant is what the statute says. Furthermore, the Petitioners filed substantial scientific evidence that the toxicity of carbon dioxide results from high concentrations and that alleged causation of global warming transforms the gas into a pollutant.

If the statutory definition of the CAA includes carbon dioxide, then the Federal courts would have no discretion to reach any other conclusion. The definition contained in the statute — not evidence or opinion — would control the outcome.

If the CAA governs carbon dioxide, the EPA not only could — but must — consider carbon dioxide as a pollutant. In that case, the EPA Administrator could decide not to regulate carbon dioxide, but only consistent with the terms of the CAA.

The Petitioners asserted that the EPA Administrator's decision not to regulate carbon dioxide and other greenhouse gases violates the terms of the CAA and must be reversed. Thus, the Supreme Court also considered whether the reasons given by the EPA were valid reasons within the CAA statute for the EPA Administrator to decide not to regulate carbon dioxide. The EPA argued that the Administrator has the power under the CAA to decide not to regulate.

The EPA Administrator argued that other actions are already being taken to increase fuel efficiency of automobiles and that (as of 2003) scientific investigation was still under way. Thus, the EPA Administrator decided not to regulate "at this time".

This case has become notable because of a widespread perception that the truth or falsehood of theories of global warming will be decided by the courts, not unlike the Scopes Monkey Trial on evolution. While this could eventually occur in later proceedings, the questions before the U.S. Supreme Court here were much more narrow, and legal in nature.

One of several reasons that the EPA Administrator declined to regulate carbon dioxide is uncertainty about whether man-made carbon dioxide emissions causes global warming. This has attracted great attention to the case (See "Update" link below.) However, the Supreme Court only decided whether the Administrator's reason is a valid reason within the CAA. The Supreme Court did not explicitly decide if it is true or untrue that man-made carbon dioxide emission causes global warming, although high-profile comments by Justices during oral argument are likely to affect the public debate.

The Petitioners argued that scientific uncertainty is not a valid basis for the EPA Administrator to decline to regulate. The question before the High Court was not whether the causation is true or untrue, but whether it is a valid reason for the Administrator to not regulate a pollutant.

The Supreme Court's decision is not a factual determination about the validity of theories about global warming. Since the Supreme Court overturned the Court of Appeals decision, a possible and probable result would be to return (remand) the case to the lower court for further proceedings consistent with the Supreme Court decision. In those further proceedings, factual inquiries would be likely which could either confirm or change the outcome in either direction. Thus, the ultimate decision may or may not involve future proceedings.


Stevens's Opinion for the Court

The petitioners were found to have standing, the Clean Air Act does give EPA the authority to regulate tailpipe emissions of greenhouse gases, and the EPA is required to review its contention that it has discretion in regulating carbon dioxide and other greenhouse gas emissions - specifically, its current rationale for not regulating was found to be inadequate, and the agency must articulate a reasonable basis in order to avoid regulation.

In addition, the majority report commented that "greenhouse gases fit well within the Clean Air Act’s capacious definition of air pollutant."

Roberts's Dissent

First, the dissent condemns the majority's 'special solicitude' conferred to Massachusetts as having no basis in Supreme Court cases dealing with standing. Roberts then argues that the alleged injury (ie. Massachusetts loss of land due to rising sea levels) is too speculative and without adequate scientific support. The dissent also finds that even if there is a possibility that the state may lose some land due to global warming, the effect of obliging the EPA to enforce automobile emissions is hypothetical at best. There is not a traceable causal connection between the EPA’s refusal to enforce emission standards and petitioner’s injuries. Finally, the dissent finds that redressability of the injuries is even more problematic given that countries such as India and China are responsible for the majority of the green house gas emissions. The Chief Justice concludes by accusing the majority of lending the Court as a convenient forum for policy debate and of transgressing the limited role afforded to the Supreme Court by the US Constitution.

Scalia's Dissent

First, Justice Scalia found that the Court has no jurisdiction to decide the case because petitioners lack standing. In his estimation, that is the end of the inquiry. However, since the majority saw fit to find standing, his dissent continued.

The main question is, "Does anything require the Administrator to make a 'judgment' whenever a petition for rulemaking is filed?" Justice Scalia sees the Court's answer to this unequivocally as yes, but with no authority to back it. He backs this assertion by explaining that the "statute says nothing at all about the reasons for which the Administrator may defer making a judgment -- the permissible reasons for deciding not to grapple with the issue at the present time. Scalia saw no basis in law for the Court's imposed limitation.

When the Court opines that "If the scientific uncertainty is so profound that it precludes EPA from making a reasoned judgment as to whether greenhouse gases contribute to global warming, EPA must say so," Scalia responded that EPA has done precisely the form of the National Research Council that researched Climate Change Science.

Resting the heart of his dissent on the Court's abdication of applying Chevron deference, he closes with the notion that no matter how important the policy issue in question, the Court should defer to the more experienced and reasoned judgment of the agency.

See also

  • Global warming
  • Effects of global warming
  • International Panel on Climate Change - Fourth Assessment Report
  • List of United States Supreme Court cases, volume 549


  1. ^ Text of Opinion
  2. ^ Questions Presented
  3. ^ Appeals Court Decision
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Massachusetts_v._Environmental_Protection_Agency". A list of authors is available in Wikipedia.
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