Court Says States May Regulate Greenhouse Gases

States may regulate greenhouse gas emissions from new cars and trucks, a federal trial court ruled last week. Rejecting automakers' arguments, the U.S. District Court in Vermont said state controls on greenhouse gas emissions do not conflict with federal fuel economy standards, which can be set only by the National Highway Traffic Safety Administration. The case builds on the U.S. Supreme Court's decision in April that vehicle emissions of CO₂, a major greenhouse gas, can be controlled under the federal Clean Air Act. States that want to regulate greenhouse gases and environmental groups hailed the Sept. 12 decision as a major victory, although automakers are considering an appeal. The same day, the governors of 13 states asked the heads of car companies to withdraw legal challenges to state regulation of greenhouse gas emissions from vehicles. "We would prefer to follow a path that encourages innovation, not litigation," the governors of Arizona, California, Connecticut, Maine, Maryland, Massachusetts, New Mexico, New York, Oregon, Pennsylvania, Rhode Island, Utah, and Washington said in a letter to the CEOs of General Motors, Chrysler, Ford, Honda, Nissan, and Toyota.