Stung by a Supreme Court ruling that it has the authority to establish vehicle emissions standards, the Environmental Protection Agency is allowing California to proceed with efforts to set the nation's first standards to cut tailpipe emissions from cars, light trucks and sport utility vehicles.
Since 2005, California has sought an exemption from the federal Clean Air Act that would allow it to set the emissions standards in hopes of reducing greenhouse gases.
The EPA had blocked California's waiver request, arguing that the authority to set fuel economy standards belonged only to the U.S. Department of Transportation.
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But Monday's 5-4 Supreme Court ruling pushed the EPA to allow California to proceed with its request and could affect an auto industry lawsuit seeking to block the state's proposed regulations.
The 2002 regulations are designed to reduce the emissions from cars and light trucks by 25 percent and from sport utility vehicles by 18 percent starting in 2009.
"We've reviewed the issues within the waiver request," EPA spokeswoman Jennifer Wood said Tuesday. "We're moving forward to the next steps of the process."
The agency next will schedule a public comment period and public hearing.
California has special authority under the federal Clean Air Act to set its own vehicle emissions standards because it began regulating air pollution before the federal government did in the 1970s.
Ten other states have adopted California's standards, and Maryland is considering doing so, but they have to wait to implement them until the EPA grants California a waiver.
"It's clear EPA has to consider California's waiver request now," said Sean Hecht, executive director of the environmental law center at the University of California, Los Angeles. "That doesn't mean it's a foregone conclusion with respect to the waiver request."
Monday's court ruling prompted movement Tuesday in a separate lawsuit brought by the auto industry to prevent California from moving forward with its regulations if it receives the waiver.
The California Air Resources Board, along with several environmental groups, officially notified U.S. District Judge Anthony Ishii of the Supreme Court's decision. In January, he placed the lawsuit on hold pending a decision by the court.
It's unclear what the next step will be in the case, which is being heard in federal court in Fresno. But both sides said the Supreme Court's decision favors their argument.
"The case will affect all of the pending litigation that California has with both the auto companies and Midwestern energy companies," California Attorney General Jerry Brown said in an interview Monday with The Associated Press.
The Natural Resources Defense Council intends to ask the judge to dismiss the case in light of the Supreme Court's ruling, spokesman Craig Noble said.
Raymond Ludwiszewski, an attorney representing the Association of International Automobile Manufacturers, interpreted the ruling by the Supreme Court as a directive that greenhouse gas regulations should be crafted at the federal level.
"I think the Supreme Court ruling makes it clear that the court viewed global warming as an issue that should be dealt with nationally and not at the state level," Ludwiszewski said Tuesday.
California's attempt to cut tailpipe emissions is a key component of the state's broader effort to reduce greenhouse gases to 1990 levels by 2020. The auto regulations could help the state reach about 17 percent of its target, Air Resources Board spokeswoman Gennet Paauwe said.
The state also has sued the six largest automakers in an attempt to collect millions of dollars it expects to spend on repairing the damage from floods, wildfires and other natural disasters that are expected to intensify as temperatures rise.
California is the world's 12th largest producer of greenhouse gases.
The auto industry also has sued Vermont, which is seeking to implement California's tailpipe regulations. That trial is scheduled to begin next week.