Via The New York Times:

WASHINGTON — The pitched battle over President Obama’s signatureclimate change policy, which is moving to the courts this week, carries considerable political, economic and historical stakes. Yet its legal fate, widely expected to be ultimately decided by the Supreme Court, could rest on a clerical error in an obscure provision of a 26-year-old law.

That error, which left conflicting amendments on power plant regulation in the Clean Air Act, will be a major focus of oral arguments by opponents of Mr. Obama’s initiative when the case is heard on Tuesday in the United States Court of Appeals for the District of Columbia Circuit.

The initiative, known as the Clean Power Plan, which Mr. Obama sees as at the heart of his climate change legacy, gave the United States critical leverage to broker the landmark 2015 Paris climate change accord. If the plan is struck down, the United States, the world’s largest carbon polluter over the centuries, will lose its main tool to cut greenhouse gas emissions. If it is upheld, it will transform the nation’s electricity system, closing hundreds of coal-fired power plants and setting in motion a wholesale shift to wind, solar and nuclear power, as well as to improved electric transmission systems.

Twenty-eight states and more than 100 companies and labor and industry groups are fighting to overturn the plan. Defending it are 18 states and dozens of environmental and public health groups that have joined forces with the Obama administration. Nearly 20 lawyers will take turns arguing the case before 10 judges — much larger than the typical three-member panel. The judges have allocated four hours to hear the arguments, rather than the usual one or two. The chief judge of the court, Merrick B. Garland, who is also Mr. Obama’s Supreme Court nominee, has recused himself.

Adding to the drama will be the presence of Mr. Obama’s mentor at Harvard Law School, Laurence H. Tribe, who will argue against the climate plan on behalf of the nation’s largest coal company, Peabody Energy.

The long-forgotten clerical error at issue in the case — State of West Virginia, et al. v. Environmental Protection Agency — involves an update to the Clean Air Act passed by Congress in 1990.

The Clean Air Act of 1970 is the legal foundation of the Clean Power Plan. An obscure provision in the law — Section 111(d) — gave the E.P.A. broad authority to regulate unknown future pollutants. At the time, carbon dioxide, the nontoxic but heat-trapping gas that is the chief cause of global warming, was not considered a pollutant.

In 1990, when Congress passed the update to the Clean Air Act, it amended Section 111(d). A version of the amendment passed by the House said that if the E.P.A. was already regulating power plant pollution under a separate section of the law, it could not use Section 111(d) to create new regulations on the same plants. A version of the amendment passed by the Senate, however, did allow such overlapping regulation.

When the two bills were merged, lawmakers forgot to strike out one of the conflicting amendments in the bleary-eyed rush to push the bill through. So it was signed into law by President George Bush with both amendments.

Opponents of the Clean Power Plan will argue on Tuesday that a strict interpretation of the House amendment would render the plan illegal.

Last year, when the E.P.A. issued the Clean Power Plan, it used Section 111(d) to justify placing new regulations on carbon dioxide emissions from coal-fired power plants. The agency has also long regulated toxic power plant pollutants, such as mercury, under a different section, 112, of the Clean Air Act.

“In 1990, Congress dramatically expanded the Clean Air Act, and when they did that, they said an industry cannot be double-regulated,” said Jeff Holmstead, a lawyer representing many of the groups suing the administration.

Sean Donahue, a lawyer for the Environmental Defense Fund who will argue this portion of the case before the court, called that legal interpretation “preposterous.”

“It’s very interesting that there was this legislative glitch,” he said. Environmentalists and the administration will argue that because the two types of pollutants are so different, the E.P.A. is justified in using two sections of the law to regulate them.

“This bizarre proposition is like exempting restaurants from food handling requirements because they are subject to the fire code,” Mr. Donahue said.

Opponents of the plan will also focus on two other main points, arguing that Mr. Obama has exceeded his executive authority.

While environmental regulations under the Clean Air Act often require states to cut pollution by using specific technology, such as affixing “scrubbers” to smokestacks, the Clean Power Plan goes further: It asks states to reduce pollution by making changes to their entire electricity systems — shutting down coal plants, and building wind and solar plants. The plan also encourages states to reduce emissions by putting in place “cap-and-trade” systems, which would create state or regional caps on emissions and allow companies to buy and sell credits to pollute.

In his first term, Mr. Obama tried but failed to push a cap-and-trade bill through Congress. Now, his opponents say, he is using regulation to force the system through.

“The E.P.A. is going beyond what it’s authorized to do by Congress and essentially creating new law,” said Ken Paxton, the attorney general of Texas, a leader in coordinating the legal opposition to the plan.

David Doniger, a lawyer for the Natural Resources Defense Council, which worked closely with the Obama administration to draft the plan, dismissed that objection, noting that the E.P.A. already uses a cap-and-trade system to regulate other sources of pollution.

Given the high stakes, the two sides have gone to unusual lengths in their preparation, including what longtime activists say is an unprecedented level of counterintelligence work. Consultants have been gathering once-confidential details about how their opponents are organizing their side of the fight, in an attempt to find embarrassing tidbits that might undermine their arguments, at least in the public’s eye.

Both sides have spent months filing Freedom of Information requests and related lawsuits to obtain email correspondence and other records from their opponents.

Environmental groups sought emails between the state attorneys general who are challenging the Clean Power Plan and executives from the coal and electric utility industries.

Lawyers and consultants paid by the energy industry have sought records showing that environmentalists have worked closely with liberal politicians who support the plan.

“Transparency is a good thing, so having more of these documents serves the public,” said Kert Davies, the executive director of a group called the Climate Investigations Center, which has helped gather counterintelligence information on opponents of the Clean Power Plan. “But it is certainly an escalating war, back and forth. The intensity has peaked.”

See the article here.