( 12-1254 ) ; American Chemistry Council v. EPA ( 12-1248 ) ; and Utility Air Regulatory Group v. EPA ( 12-1146 ) . Coalition of states , utilities is challenging the government 's authority to regulate air pollution . At issue is whether the EPA can tighten emission standards for all natural gas sources . The government says the tighter rules are an attempt to stem the effects of global warming . Business groups say regulations are hurting the economy and limiting innovation .
Coalition of states , utilities is challenging the government 's authority to regulate air pollution . At issue is whether the EPA can tighten emission standards for all natural gas sources . The government says the tighter rules are an attempt to stem the effects of global warming . Business groups say regulations are hurting the economy and limiting innovation .