schwit1 writes "The Supreme Court on Monday rejected a global warming lawsuit against five big power companies, its most important environmental ruling since 2007 and a victory for the utilities and the Obama administration. The justices unanimously overturned a ruling by a US appeals court that the lawsuit now involving six states can proceed in an effort to force the coal-burning plants to cut emissions of gases that contribute to climate change. In a defeat for environmentalists, the Supreme Court agreed with the companies that regulating greenhouse gases should be left to the Environmental Protection Agency under the clean air laws. The ruling stemmed from a 2004 lawsuit claiming the five electric utilities have created a public nuisance by contributing to climate change. The lawsuit wanted a federal judge to order them to cut their carbon dioxide emissions."