In October, the Supreme Court will begin hearing arguments in a case of extraordinary significance: whether or not the feds can regulate carbon dioxide as a pollutant under the Clean Air Act. While enviros (and a dozen states) have been trying to push the case to SCOTUS for a while, they are nonetheless nervous. The court has been substantially made over with the recent additions of John Roberts and Samuel Alito, but nobody's entirely sure how exactly it's changed. Muddled decisions like the recent one on the Clean Water Act do not portend victory, or even clarity. (More on this from Carl Pope.)
Two questions are at issue. Quoting from the appeal (PDF):
1. Whether the EPA Administrator may decline to issue emission standards for motor vehicles based on policy considerations not enumerated in section 202(a)(1).
2. Whether the EPA Administrator has authority to regulate carbon dioxide and other air pollutants associated with climate change under section 202(a)(1).
In other words, can the EPA regulate CO2, and if it can, is it required to. That's simple enough, but I've not seen much in-depth analysis of what the ramifications various rulings might be. In the unlikely event the court rules that the EPA has the authority to regulate CO2, and must use that authority, it would be epochal. But what about various splits?