In May 2010, the Environmental Protection Agency (EPA) issued a rule setting standards for motor vehicle greenhouse gas emissions. By creating these standards, EPA is implicitly regulating fuel economy. Because the rule also obligates EPA to regulate greenhouse gases from stationary sources, the agency is now determining national policy on climate change. EPA has asserted that it is simply implementing the Clean Air Act. But the Clean Air Act was neither designed nor intended to regulate greenhouse gases, and it provides no authority to regulate fuel economy.
Last year, Congress declined to give EPA explicit authority to regulate greenhouse gases when Senate leaders abandoned cap-and-trade legislation. A key selling point for the Waxman-Markey cap-and-trade bill was that it would exempt greenhouse gases from regulation under several Clean Air Act programs.2 If instead of introducing a cap-and-trade bill, Reps. Waxman and Markey had introduced legislation authorizing EPA to do exactly what it is doing now—regulate greenhouse gases through the Clean Air Act as it sees fit—the bill would have been rejected. The notion that Congress gave EPA such authority in 1970, almost two decades before global warming emerged as a public concern, and five years before Congress enacted the first fuel economy statute, defies common sense.