[JURIST] The US Supreme Court [official website, JURIST news archive] heard oral arguments [day call, PDF; merit briefs] Tuesday in American Electric Power Co. v. Connecticut [oral arguments transcript, PDF; JURIST report] regarding whether electric utilities contributed to global warming [JURIST news archive]. The court is being asked to decide (1) whether states and private parties have standing to seek judicially-fashioned emissions caps on five utilities for their alleged contribution to harms claimed to arise from global climate change caused by more than a century of emissions by billions of independent sources; (2) whether a cause of action to cap carbon dioxide emissions can be implied under federal common law where no statute creates such a cause of action, and the Clean Air Act speaks directly to the same subject matter and assigns federal responsibility for regulating such emissions to the Environmental Protection Agency; and (3) whether claims seeking to cap defendants' carbon dioxide emissions at "reasonable" levels, based on a court's weighing of the potential risks of climate change against the socioeconomic utility of defendants' conduct, would be governed by "judicially discoverable and manageable standards" or could be resolved without "initial policy determination[s] of a kind clearly for nonjudicial discretion." The US Court of Appeals for the Second Circuit ruled in 2009 that states can sue power companies for emitting carbon dioxide, reversing a district court decision [JURIST reports] that found the plaintiffs' claim was a non-justiciable political question. The lawsuit was brought by eight statesCalifornia, Connecticut, Iowa, New Jersey, New York, Rhode Island, Vermont and Wisconsinas well as New York City and three land trusts, against coal-burning utilities American Electric Power, Southern Company, Xcel Energy, Cinergy Corporation [corporate websites] and the Tennessee Valley Authority [official website]. At oral argument Tuesday, the justices appeared skeptical of the states' arguments, implying that the Environmental Protection Agency would be better equipped to deal with emissions standards than federal courts. The Obama administration has sided with the power companies.