Excerpt from Energy and Climate Debate:

The Supreme Court partially upheld and partially rejected June 23 a set of Environmental Protection Agency greenhouse gas regulations for major pollution sources, following a legal challenge from the utility industry. The 5-4 ruling does not impact the agency’s June 2 proposed CO2 standards for existing power plants, nor does it limit the agency’s overall ability to regulate greenhouse gases. The court ruled that the agency cannot require Title V and Prevention of Significant Deterioration pre-construction stationary source air permits based solely on the release of GHGs, but that emission sources that already need those permits should have to use the best available technology to control their emissions. While reading his decision, Justice Antonin Scalia said that though he believes the agency overstepped its statutory boundaries when crafting its tailoring rule, the court’s ruling should impact a very small percentage of regulated entities. Furthermore, the court found today that its 2007 decision in Massachusetts v. EPA that the Clean Air Act’s use of the term “air pollutant,” which it recognizes to be an imprecise term, includes GHGs does not preclude the agency from taking a more narrow approach elsewhere.