U.S. Supreme Court: No common law climate change lawsuits allowed

The U.S. Supreme Court has put the kibosh on an effort to invoke the common law to force greenhouse gas emission reductions.

In a decision issued Monday, the high court ruled that the enactment of the Clean Air Act into law gives the U.S. Environmental Protection Agency, not the courts, the power to limit greenhouse gas pollution of the atmosphere and precludes plaintiffs from invoking the old doctrine of nuisance to respond to climate change.

"The critical point is that Congress delegated to EPA the decision whether and how to regulate carbon-dioxide emissions from power plants; the delegation is what displaces federal common law," wrote Justice Ruth Bader Ginsburg in a unanimous opinion.

The plaintiffs, which include several states, New York City, and a number of private land-trusts, argued that four private utilities and the Tennessee Valley Authority created a nuisance by emitting 650 million tons of carbon dioxide into the atmosphere each year.

That collective emission of carbon dioxide is equivalent to ten percent of the total annual domestic carbon dioxide pollution in the United States and about 2.5 percent of the total human-caused emission of carbon dioxide worldwide.

The complaints filed in the case alleged that the emissions violate either the federal common law of public nuisance or a similar doctrine existing in state law. The basis of the claims was that the defendants' emissions would harm the environment and human health.

They asked a federal district court to impose a ceiling on the entities' emissions, which would get tighter in successive years.

The U.S. District Court for the Southern District of New York had dismissed the complaints on grounds that the issues raised in them are "political questions" beyond the jurisdiction of the federal judiciary, but the U.S. Court of Appeals for the Second Circuit reversed that decision.

Ginsburg's opinion discussed a technical area of jurisprudence arising from the need to allow the development of some federal common law. However, all of the participating justices agreed that this doctrine was of no help to the plaintiffs because Congress spoke directly to the issue at the heart of their case when it enacted the Clean Air Act.

“When Congress addresses a question previously governed by a decision rested on federal common law, the need for such an unusual exercise of law-making by federal courts disappears,” the Court said.

The Court, in a 2007 decision called Massachusetts v. EPA, has already held that the Clean Air Act authorizes the federal government to impose regulations that limit greenhouse gas emissions from power plants, other industrial sources, and motor vehicles.

The Obama administration has been moving to use that authority.

In 2010 EPA and the U.S. Department of Transportation finalized rules that limit emissions of carbon dioxide and other heat-trapping pollutants from some motor vehicles. EPA is expected to issue a proposed regulation limiting such emissions from fossil fuel-burning power plants next month.

Justice Ginsburg's opinion did not address the defendants' argument that the plaintiffs lacked standing to bring the lawsuits against them. In Massachusetts v. EPA the Court had ruled that states have standing to force EPA to use the regulatory authority granted the agency by federal statute.

She wrote, however, that the Court divided 4-4 on this question. Under the rules of the Supreme Court, a tie vote on any issue in dispute means that the lower court's decision on the point is affirmed.

It is likely, however, that Justice Elena Kagan, who did not participate in the case, would have voted in favor of standing for at least some of the plaintiffs.

The justices also split on the question whether the "political question" doctrine barred federal courts from deciding cases raising common law arguments against environmental harms.

The case is American Electric Power Co., et al., v. Connecticut, et al., No. 10-174.