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Also today, the Supreme Court made two major rulings on the environment. One gives the Environmental Protection Agency the go-ahead to regulate greenhouse gas emissions. The other sends a rebuke to the owners of dirty coal-fired power plants.
NPR's Elizabeth Shogren has the details.
ELIZABETH SHOGREN: It was kind of like when Dorothy in "The Wizard of Oz" learned she always had the power to go home. The Supreme Court told the Environmental Protection Agency it does have the authority to regulate the greenhouse gases that contribute to climate change. Bush administration officials had argued that they didn't have that power, and so they couldn't require cars to reduce emissions. Several states and environmental groups sued the EPA, arguing that it did have that power and should use it.
Law professor Lisa Heinzerling from Georgetown University represented the states. She says the ruling has implications not just for car emissions, but for power plants, factories, and other sources of greenhouse gases.
Professor LISA HEINZERLING (Law, Georgetown University): It's a huge deal. It is hard to overstate the importance of this.
SHOGREN: The ruling does not require the EPA to regulate. But Heinzerling says, for the EPA to avoid regulating, it would have to show that these emissions don't endanger public health or welfare.
Prof. HEINZERLING: I think it will be extremely difficult and I would venture to say impossible for them to conclude based on the scientific evidence we have that you cannot anticipate that greenhouse gases will endanger public health or welfare.
SHOGREN: EPA officials declined to go on tape. An EPA press release says the agency is reviewing the court ruling. The ruling could put the EPA in a difficult position because so far President Bush has rejected mandatory cuts in greenhouse gas emissions. In the meantime, environmentalists and state officials say the ruling opens the door for states to regulate greenhouse gas emissions from cars. A dozen states, led by California, have adopted or are in the process of adopting such rules. They need the EPA's okay to go ahead, and Heinzerling says the Supreme Court ruling will make it hard for EPA officials to say no.
Prof. HEINZERLING: I can't imagine that they wouldn't. I don't see any legal basis for refusing to allow California and other states to enact standards for automobiles after this ruling.
SHOGREN: The main auto industry trade group wouldn't comment on the ruling for tape. But Dan Riedinger, from Edison Electric Institute, says his industry doesn't want the EPA to set standards.
Mr. DAN RIEDINGER (Spokesman, Edison Electric Institute): If greenhouse gases are going to be regulated - and obviously a lot of people think that that's inevitable - we would far rather it come from the U.S. Congress.
SHOGREN: The other big Supreme Court decision could also have a big impact on power plants and their pollution. Attorney Blan Holman, from the Southern Environmental Law Center, worked on the case for environmental groups.
Mr. BLAN HOLMAN (Senior Attorney, Southern Environmental Law Center): The case is all about old coal-fired power plants and what happens when you rebuild them. Do you have to put air pollution controls on them or do you not?
SHOGREN: Holman is talking about the equipment that filters out fine particles and smog. Those pollutants cause thousands of early deaths and many emergency room visits every year. The EPA, environmental groups and states are suing several power companies for failing to install pollution controls. In this case, the Supreme Court decided against Duke Energy. Tom Williams represents Duke.
Mr. TOM WILLIAMS (Director of Public Affairs, Duke Energy): It's a major setback to the case and it's something that is regrettable for us, but it's something that is not shutting down the case by any means.
SHOGREN: The Supreme Court was deciding whether you look at annual or hourly emissions to decide if emissions have increased and pollution control should be installed. The Supreme Court says annual emissions are what matters, but the power companies have other ways to defend their position.
Mr. WILLIAMS: It's our contention in this case that we did nothing wrong in the first place, which is why we're going to continue to address this in the lower courts.
SHOGREN: But environmentalists say the ruling will provide a strong incentive to clean up many of the dirtiest coal-fired power plants in the country, and they say that both rulings together suggest that the Supreme Court is far greener than anyone realized.
Elizabeth Shogren, NPR News, Washington.