The fight over global warming and whether to limit carbon pollution from coal-fired power plants must be resolved by the Environmental Protection Agency, the Supreme Court said, killing a suit in federal court brought against the nation’s five largest electric power companies.

The 8-0 decision Monday was a setback — but not a surprise — for environmentalists. The outcome puts more pressure on the Obama administration and the EPA to follow through with promises to propose new regulations in the fall that will restrict carbon pollution from power plants.

The EPA under President Obama has already adopted stricter emissions standards for cars and trucks. However, more ambitious moves contemplated by the administration could be difficult to implement because the Republican-led House has voiced opposition to new regulations that would affect energy producers.

Eight states had filed suit against Midwest and Southern power producers based on the old doctrine that a state or a private party could file a “public nuisance” suit against another party for polluting its air or water.


In throwing out the suit, Justice Ruth Bader Ginsburg said it posed a classic “who decides” question. In this instance, she said, it is clear that environmental policy should be decided by the EPA, not by a single federal judge overseeing a legal dispute.

But the lawsuit that all but ended Monday began in quite a different era. In 2004, the George W. Bush administration maintained the federal government had no legal authority to attack the greenhouses gases that are believed to cause climate change. The EPA said at the time that the Clean Air Act dealt only with traditional pollution, such as smog, but not normally benign carbon dioxide.

Frustrated by the inaction, the states, including California, New York and Connecticut, joined with environmentalists in launching the suit against American Electric Power Co. and four other power producers. In recent decades, such “nuisance” suits had all but disappeared. Congress adopted the Clean Air Act and the Clean Water Act in the early 1970s, and environmental disputes turned on interpretations of those laws.

Nonetheless, the U.S. appeals court in New York allowed the global warming suit to go forward because the government had not adopted limits on carbon pollution from power plants.


In explaining why the suit was killed, Ginsburg pointed out that the court had ruled in 2007 that the EPA had the authority to regulate greenhouses gases under the Clean Air Act. That decision undercut the need for a separate lawsuit dealing with the same problem, she said.

“The EPA is currently engaged in a rulemaking to decide whether the agency should set limits on emissions from domestic power plants. The Clean Air Act, in our judgment, leaves no room for a parallel track” that would call upon a judge to decide on the need for regulations, she said.

Peter Keisler, the former Justice Department lawyer who represented power companies, said the ruling permitted the companies to continue to “provide vital services to the public … without the threat of federal ‘climate change tort litigation.’ ”

David Doniger, a climate change expert at the Natural Resources Defense Council, said the ruling “puts a spotlight on EPA and makes it more important that the EPA act.”


All the justices joined Ginsburg’s opinion in American Electric Power Co. vs. Connecticut, except Justice Sonia Sotomayor. She was on the appeals court in New York that decided the matter earlier. Ginsburg noted the ruling did not prevent the lawyers who brought the case in federal court from trying again under state law.

Originally, the suit spoke for eight states. In addition to California, New York and Connecticut, they included Iowa, New Jersey, Rhode Island, Vermont and Wisconsin. More recently, New Jersey and Wisconsin backed away after Republican governors took office.

david.savage@latimes.com