The Supreme Court ordered the federal government on Monday to take a fresh look at regulating carbon dioxide emissions from cars, a rebuke to Bush administration policy on global warming.
In a 5-4 decision, the court said the Clean Air Act gives the Environmental Protection Agency the authority to regulate the emissions of carbon dioxide and other greenhouse gases from cars.
Greenhouse gases are air pollutants under the landmark environmental law, Justice John Paul Stevens said in his majority opinion.
The court had three questions before it.
--Do states have the right to sue the EPA to challenge its decision?
--Does the Clean Air Act give EPA the authority to regulate tailpipe emissions of greenhouse gases?
--Does EPA have the discretion not to regulate those emissions?
The court said yes to the first two questions. On the third, it ordered EPA to re-evaluate its contention it has the discretion not to regulate tailpipe emissions. The court said the agency has so far provided a "laundry list" of reasons that include foreign policy considerations.
The majority said the agency must tie its rationale more closely to the Clean Air Act.
"EPA has offered no reasoned explanation for its refusal to decide whether greenhouse gases cause or contribute to climate change," Stevens said. He was joined by his liberal colleagues, Justices Stephen Breyer, Ruth Bader Ginsburg and David Souter, and the court's swing voter, Justice Anthony Kennedy.
The lawsuit was filed by 12 states and 13 environmental groups that had grown frustrated by the Bush administration's inaction on global warming