On Tuesday, the Supreme Court of the United States granted‎ six separate petitions for ‎certiorari from a decision of the Federal Circuit Court for the District of Columbia upholding ‎EPA’s efforts to regulate greenhouse gas (GHG) emissions under the Clean Air Act (CAA). The ‎petitions will be consolidated and the Court’s review will be limited to a single question: "Whether EPA permissibly determined that its ‎regulation of greenhouse gas emissions from new motor vehicles triggered permitting ‎requirements under the Clean Air Act for stationary sources that emit greenhouse gases." The ‎petitioners include the State of Texas, the U.S. Chamber of Commerce, and industry associations ‎of energy producers and users.‎

The Supreme Court ruled in 2007 that EPA has the authority to regulate GHG emissions ‎‎(Massachusetts v. EPA) and cited EPA's developing regulatory framework in its ‎‎2011 decision to dismiss claims related to damages caused by climate change (AEP v. Connecticut).‎  Still, its decision to review the D.C. Circuit Court's opinion in this case is a win for opponents of GHG regulation since it signals the Court's interest in potentially scaling back EPA's efforts.

The decision being appealed resulted from the litigation titled Coalition for Responsible ‎Regulation, Inc. et al., v. Environmental Protection Agency (D.C. Cir. Index No. 09-1322). This ‎case is a consolidation of dozens of separate lawsuits challenging EPA’s 2009 endangerment ‎finding and the resulting rules that propose GHG emission limits for light-duty vehicles (tailpipe ‎rule) and large, stationary sources (timing and tailoring rules). You can read more about the ‎circuit court’s opinion here.‎ The Supreme Court also denied three petitions arising out of this ‎case and declined to consider some of the largest issues, including the validity of EPA’s ‎endangerment finding and EPA’s adaptation of the CAA’s permitting provisions to GHG ‎emissions through the tailoring rule.‎