[JURIST] California filed a lawsuit [complaint, PDF; press release] Thursday in the US District Court for the District of Columbia against the US Environmental Protection Agency (EPA) [official website] in an effort to force the EPA to come to a decision on whether California can impose greenhouse gas emissions standards on cars and light trucks. The EPA considered California's request for a waiver [JURIST report] of preemption for its greenhouse gas emission standards for new cars in May, but has not come to a decision. The standards would require car manufacturers to cut emissions by 25 percent from cars and light trucks, and 18 percent from SUVs, starting with the 2009 model year. California's Air Resources Board [official website] adopted the greenhouse gas standards in 2004 [press release], but it cannot mandate them unless the EPA grants a waiver of the lighter Federal Clean Air Act (CAA) [text] standards. California is the only state permitted to seek a waiver under the CAA, but if granted, other states have the option of choosing between the federal standards and those of California. At least 11 states have indicated that they would follow the California standard.

Many auto manufacturers, represented by the Alliance of Automobile Manufacturers [advocacy website], are opposed to the stricter standards [hearing testimony transcript], arguing that by regulating the emissions standards of automobiles, California is in effect regulating fuel economy standards, which can only be regulated by the federal government. The auto industry is also suing California [JURIST report] to block the standards from going into effect. The Boston Globe has more. The San Francisco Chronicle has local coverage.