The D.C. Circuit upheld an EPA regulation that requires automobile manufacturers to use "commercially available" fuel when testing the emissions of new vehicles under the CAA. Several producers of E30, a fuel that contains 30% ethanol, argued that a fuel shouldn't have to be commercially available i...

A district court ordered Oklahoma to file a brief by July 16 explaining why the court should have jurisdiction over the state's lawsuit challenging EPA's proposed "Clean Power Plan" to reduce carbon dioxide emissions on a nationwide basis. Numerous states, including Oklahoma, recently filed a case i...

The U.S. Supreme Court reversed and remanded EPA's rule limiting hazardous air pollutant emissions from power plants, holding that the Agency interpreted CAA §112(n)(1)(A) unreasonably when it deemed cost irrelevant to the decision to regulate power plants. CAA §112(n)(1) directs EPA to regulate e...