Commonwealth of Massachusetts v. EPA
Argued: November 29, 2006
Decided: April 2, 2007
Facts
The legal system in the United States is an adversarial system. This means that two parties, or adversaries,
represent their positions to a neutral observer, either a judge or jury, who determines the truth of the case.
Under this adversarial system, judges do not make decisions about laws when there is no actual dispute
between a plaintiff and a defendant. Moreover, to maintain the separation of powers between the three
branches of government, Article III of the Constitution explicitly states that federal courts may hear only
“cases” and “controversies.” So if the plaintiff is not (or will not be) harmed by a law – that is, the plaintiff
lacks standing – then a court will not hear the case. One of the primary issues in Commonwealth of Massachusetts
v. EPA was whether the plaintiffs had standing to challenge the Environmental Protection Agency’s (“EPA”)
decision to not regulate greenhouse gases.
Many respected scientists believe that a significant increase in greenhouse gases is causing global warming.
These greenhouse gases, including carbon dioxide, act like the ceiling of a greenhouse by trapping solar
energy and heat in the earth’s atmosphere. Although Congress has not specifically acted to cut greenhouse
gas emissions, Section 202 of the Clean Air Act regulates emissions of any “air pollutant” from new motor
vehicles which “may reasonably be anticipated to endanger public health or welfare,” including “effects
on…weather…and climate.”
In light of Section 202 of the Clean Air Act, several environmental groups as well as several state and local
governments, including Massachusetts, asked the EPA to regulate greenhouse gas emissions from new cars.
The EPA denied their request. It stated that the Clean Air Act does not authorize it to issue regulations to
address global climate change and that even if the EPA had that authority it would be unwise to do so now.
The environmental groups, joined by several states and cities, petitioned the U.S. Court of Appeals for the
D.C. Circuit for a review of the EPA’s decision. But the plaintiffs had to answer a major question before
moving forward with their case against the EPA: did they have standing to bring their case in federal court?
In a split decision, the court of appeals did not bar the plaintiffs based on standing, but it ruled against them
on the meaning of the Clean Air Act, stating that the EPA properly exercised its discretion to not regulate
greenhouse gases. The plaintiffs appealed to the Supreme Court.
Issue
Do states, cities, or environmental groups have standing to challenge in federal court the EPA’s decision not
to regulate greenhouse emissions under the Clean Air Act?
Statutes and Precedents
 Section 202 of the Clean Air Act
“The [EPA] Administrator shall by regulation prescribe (and from time to time revise) in accordance
with the provisions of this section, 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 .
. .”
The Act defines “air pollutant” to include “any air pollution agent or combination of such agents,
including any physical, chemical, biological, radioactive … substance or matter which is emitted into
or otherwise enters the ambient air.” “Welfare” is also defined broadly: among other things, it
includes “effects on …weather …and climate.”
 Lujan v. Defenders of Wildlife (1992)
In 1983, environmental groups sued the Secretary of the Interior for refusing to issue regulations
under the Endangered Species Act that would protect threatened and endangered animals in foreign
countries. The Secretary of the Interior argued that the environmental groups had no standing to
bring suit because they were not injured by the Secretary’s decision. The environmental groups said
that they were injured because if the animals were not protected they would not be able to see them
some time in the future.
The Supreme Court ruled in favor of the Secretary. It explained that standing exists only if (1) the
plaintiff has suffered an injury that is “concrete and personal”; (2) the injury is connected to what the
plaintiff is complaining about; and (3) the injury can be redressed by a decision in the plaintiff’s favor.
According to the Court, the environmental groups could not show a “real and immediate” injury
because it was not clear when any members of the environmental groups would be traveling to a
foreign country to see one of the endangered animals. In addition, a plurality of the Court said that it
was mere speculation that changing the Department of Interior’s regulations would somehow redress
the injury. This decision was based, in part, on the fact that United States agencies supply only a small
fraction of the aid to protect the animals in foreign countries. Even if the Secretary’s regulation was
changed to protect foreign animals, it is “entirely conjectural” that the U.S. funding would reduce
harm to those animals.
Arguments for the Commonwealth of Massachusetts
 Massachusetts will suffer an actual and imminent injury. Scientists and engineers predict drastic
consequences from global warming caused by greenhouse gases, including loss of or damage to state
property from rising sea levels, increased health costs because of the spread of diseases, and increased
costs from reduction in water storage caused by less snow in the mountains.
 Carbon dioxide emissions by U.S. automobiles have a significant impact on global warming. In fact,
emissions from the U.S. transportation sector alone are greater than total emissions in every other
country, except China.
 Reductions in carbon dioxide and other greenhouse gases from vehicles in the United States will have
a meaningful impact, delaying and reducing some of the adverse impacts of global warming.
 A state has a special interest in being involved in the case and should not be barred by standing.
Massachusetts, for example, cannot invade another state to force reductions in greenhouse emissions
or negotiate a treaty with China to reduce emissions. Its only recourse is with the Clean Air Act.
Arguments for the Environmental Protection Agency
 Massachusetts has failed to show any harm to it. Even if it is true that emissions of certain gases will
cause an increase in the earth’s temperature, this is harmful to humanity as a whole, not to
Massachusetts in particular.
 The alleged injuries were not caused by the EPA’s decision not to regulate emissions of greenhouse
gases from motor vehicles. The greenhouse emissions from new U.S. cars are not responsible for
rises in sea level. There are too many other factors to consider.
 Massachusetts alleged injuries cannot be redressed by a decision in its favor. Because carbon dioxide
emissions from U.S. motor vehicles represent a tiny fraction of all greenhouse gases, it is entirely
speculative that reducing those gases will stop Massachusetts from losing coastal land or suffering
another injury.
 The injuries are not redressable because increases in greenhouse gases by developing countries, like
China and India, will more than offset any reduction by the United States.
 When there is no standing, the courts have no business deciding a case. Determining whether
greenhouse gases should be regulated is the job of the executive and legislative branches.
Decision
Justice Stevens wrote the opinion of the court, which Justices Breyer, Ginsburg, Kennedy, and Souter joined.
Chief Justice Roberts and Justice Scalia wrote dissenting opinions. They were joined by each other, Justice
Alito, and Justice Thomas.
Majority
In a 5-4 decision, the Court ruled in favor of Massachusetts and the other plaintiffs. The Court decided that
Massachusetts met all three requirements for standing, in part, because a state has a special stake in the
outcome of the case. First, the Court explained that Massachusetts faces significant injuries: global warming
brings about a number of environmental changes, such as rising sea levels that will destroy a large part of the
state’s coastal property. Second, the refusal of the EPA to regulate carbon dioxide from motor vehicles
“contributes” to Massachusetts’ injuries. Motor vehicles, the Court explained, emit an enormous quantity of
carbon dioxide into the atmosphere. In fact, just counting carbon dioxide emissions from its transportation
sector, the United States would be the third largest emitter of carbon dioxide in the world. Third, regulating
motor-vehicle emissions will not fix global warming, but it will slow the pace of global warming no matter
what happens elsewhere in the world.
Having concluded that Massachusetts had standing, the Court ruled that the EPA has authority under the
Clean Air Act to regulate greenhouse gases in motor vehicles. According to the Court, the statute’s language
was clear: the EPA may regulate “any” air pollutant. In addition, the broad language of the Clean Air Act
showed that Congress wanted the law to be flexible, so that the EPA could regulate new pollutants as
circumstances changed. The Court also made clear that the EPA must regulate emissions if it finds that the
emissions endanger public health or welfare. In other words, it can decide to not regulate greenhouse gases
if, and only if, it determines that greenhouse gases do not contribute to global warming.
Dissent
The Chief Justice disagreed with the majority on the standing issue. Although he made clear that his
conclusion “involves no judgment on whether global warming exists,” he argued that Massachusetts failed the
three-part standing test. First, global warming is a worldwide phenomenon – it changes the atmosphere
around the world – but does not injure Massachusetts in particular. He said that it is “pure conjecture” that
Massachusetts will lose coastal land because of rising sea levels. Second, it is speculative to say that
greenhouse gas emissions from new motor vehicles, which represent only a tiny faction of all greenhouse
gases, will impact a 150-year global phenomenon, and thus reduce the chances of Massachusetts losing coast
line. And, third, because 80% of greenhouse gas emissions originate outside the United States, it is possible
that reducing new automobile emissions in the United States will do little to redress Massachusetts’ alleged
injury. Increases in greenhouse emission from countries like India and China may offset any reduction in the
United States. For this reason, he argues, the majority is wrong to claim that it is likely that regulating
emissions here in the United States will prevent the loss of Massachusetts coastal land.