Spurring the EPA on greenhouse gases

When the Supreme Court rules in favor of power plants in a global warming case, the initial reaction is dismay. But the effort to control carbon dioxide and other greenhouse gas emissions won’t be greatly set back by last week’s unanimous decision rejecting a lawsuit by California and five other states against four power companies and the Tennessee Valley Authority.

The states had sought to limit the greenhouse gases emitted by the power plants, but their lawsuit had a problem: It was brought not under the Clean Air Act but under the common law doctrine known as “public nuisance.” Writing for the court, Justice Ruth Bader Ginsburg held that such a suit was ruled out by the existence of the Environmental Protection Agency and the Clean Air Act, which, according to a previous decision, authorizes the agency to regulate greenhouse gases as a pollutant. As Ginsburg said in oral arguments, a victory for the states would “set up a district judge, who does not have the resources, the expertise, as a kind of super EPA.”

This 8-0 decision does not mean there is no role for the courts in protecting the environment. In 2007, the Supreme Court ruled that greenhouse gases were pollutants under the Clean Air Act and that the EPA had the right to regulate them. And the court can entertain challenges regarding the interpretation of that law. But last week’s decision sends the message that in this area as in others, the court need not address a problem that is already engaging the political branches of government.

The EPA — too slowly — is working on rules for limiting greenhouse gases from power plants. It should see this decision as a spur to set meaningful curbs. Meanwhile, the political debate over climate change continues. Environmentalists need to be vigilant on every front. Global warming denial is still common, as is opposition to supposedly burdensome government regulation. And some members of Congress oppose an effective EPA. Having been deferred to by the court, the agency now needs to make the most of its mandate.