The United States Supreme Court heard oral arguments on January 14 in a case initiated by the Engine Manufacturers Association (EMA) and the Western States Petroleum Association (WSPA) challenging a purchasing ban imposed on certain new vehicles by the South Coast Air Quality Management District (AQMD), the local air quality agency for the Los Angeles area. The regulations were put into force two years ago.The case, EMA and WSPA vs. South Coast AQMD, seeks to overturn the South Coast's fleet rules that prevent certain fleet owners from buying several types of new vehicles, including advanced clean-technology vehicles powered by gasoline and diesel engines. The case focuses on preserving the rights of public and private fleet owners to purchase any new car or truck that is certified to meet the stringent emission standards established under the federal Clean Air Act by the U.S. Environmental Protection Agency (EPA) and the California Air Resources Board (ARB). Air quality is not an issue in the case since the prohibited vehicles can achieve emission levels comparable to those allowed under the rules. In oral arguments, Carter Phillips, the attorney representing EMA and WSPA, stated that the fleet rules are a form of local regulation that is expressly preempted and prohibited by the federal Clean Air Act, and that only the US EPA or ARB can legally establish emission standards for new vehicles and engines. According to Phillips, arbitrarily prohibiting fleet owners from purchasing certain vehicles that otherwise meet all current federal and California emission standards, the South Coast has clearly violated the section of the Clean Air Act that preempts state and local governments from establishing emission standards. Significantly, the U.S. Justice Department entered the case to support EMA and WSPA's arguments. In his presentation to the Court, Solicitor General Theodore Olson noted that the United States government has the general duty to uphold and defend the primacy of federal law, and the specific duty to uphold Congress' careful allocation of responsibility to EPA, not to states or local jurisdictions, to regulate emissions from new motor vehicles. He further stated that the federal government's position is that Section 209(a) of the Clean Air Act expressly preempts local district rules that establish new vehicle standards, and that the fleet rules in question are, in fact, precisely such prohibited and unlawful standards. "The oral arguments before the Court today clearly laid out the central issue in this case," said Jed Mandel, EMA President. "That issue is whether the United States will maintain the Congressionally-mandated system of setting new-vehicle emission standards on a nationwide basis, or whether we will fall into a chaotic patchwork of inconsistent standards developed by each and every local government. What value are national emissions regulations for new cars, trucks, and buses if every local government has the authority to ban the purchase and sale of those vehicles and establish its own unique standards?"Several industry groups involved in the transportation sector joined EMA and WSPA in bringing the case to the Supreme Court. They include the Alliance of Automobile Manufacturers, American Petroleum Institute, American Trucking Associations, National Petrochemical Refiners Association, National Manufacturers Association, National Automobile Dealers Association, Truck Manufacturers Association, and the United States Chamber of Commerce. A decision and ruling by the Court is expected before June.