SUPREME COURT HEARS ARGUMENTS ON LIMITING CO2.

Byline: LISA FRIEDMAN Washington Bureau

WASHINGTON -- U.S. Supreme Court justices on Wednesday began weighing whether to force the federal EPA to regulate tailpipe emissions in a high-stakes case that could test California's new greenhouse gas laws and set the stage for congressional action on global warming.

Led by Massachusetts and California, a dozen states argued that they face an imminent environmental threat unless the Environmental Protection Agency acts, and attorney James Milkey likened the harm from emissions to ``lighting a fuse on a bomb.''

But Deputy Solicitor General Gregory Garre argued that the EPA lacks the power to regulate carbon dioxide as a pollutant under the Clean Air Act. And even if it had the authority, Garre said, it would not act because of ``the substantial scientific uncertainty surrounding global climate change.''

For California, the outcome of the case could determine whether it can proceed with sweeping regulations requiring new vehicles sold in the state to cut tailpipe emissions by 30 percent by 2016.

Automakers have sued to block the rules, which are set to start in 2009.

If the justices rule that the federal government must regulate tailpipe emissions, it could free the state and others with similar laws from legal threats.

But if justices rule that the Clean Air Act does not cover climate change, emissions-reduction laws could be stopped in their tracks.

``It would make it very difficult for California to regulate greenhouse gas emissions from cars,'' Sierra Club attorney David Bookbinder said. ``It would jeopardize all the work that California has done.''

State Air Resources Board spokesman Jerry Martin agreed. While California has the authority to set its own vehicle standards, he said, it must receive an EPA waiver of more lenient federal standards allowing it to enforce the law.

If the court rules that the agency does not have to rule on greenhouse gas emissions, the waiver will likely never come, he said.

``Without that waiver, we don't have the ability to enforce our regulation,'' Martin said.

Members of Congress also kept a close eye on Wednesday's Supreme Court proceedings.

U.S. Sen. Barbara Boxer, who has vowed to make global warming a top priority when she takes control of the Senate Environment and Public Works committee next year, said she is preparing for the worst-case scenario, in which the court decides the EPA has no authority to regulate.

``I would quickly introduce legislation to amend the Clean Air Act to give the EPA the authority,'' Boxer said in a statement.

``This is a very difficult decision for California,'' said Boxer, D-Calif. ``From my perspective, I don't see how you could come to any other conclusion that the Clean Air Act does include the regulation of carbon dioxide.''

Rep. Henry Waxman, D-Los Angeles, who has introduced legislation to cut emissions by 80 percent by 2050, argued that Congress has already given the EPA authority to regulate carbon dioxide.

The Bush administration, he charged, ``has tried everything it can to halt or slow efforts to combat global warming, including denying that they have the authority to do so.''

The justices, meanwhile, appeared divided Wednesday as they considered the court's first-ever global warming case.

Justice Antonin Scalia was skeptical that states had the legal standing to challenge the EPA's decision not to regulate emissions.

And Chief Justice John Roberts and Justice Samuel Alito both noted that emissions from new motor vehicles amount to just 6 percent of worldwide greenhouse gases.

The states' arguments that they would in fact see an environmental advantage from EPA rules, Roberts told Milkey, ``strikes me as sort of spitting out conjecture on conjecture, the sort that we disapprove of.''

Justices David H. Souter and Stephen G. Breyer, on the other hand, appeared to attack the EPA's contention that the states did not have standing to sue.

``They don't have to show that (new emission standards) will stop global warming,'' Souter said. ``It will reduce the degree of global warming and reduce the degree of coastal loss.''

Several court watchers are predicting the deciding vote will be cast by Justice Anthony Kennedy, who did not indicate any clear leanings.

lisa.friedman(at)langnews.com

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