WASHINGTON — In a major setback for President Barack Obama's climate change agenda, the Supreme Court on Tuesday temporarily blocked the administration's effort to combat global warming by regulating emissions from coal-fired power plants.
But the Supreme Court's willingness to issue a stay while the case proceeds was an early hint that the program could face a skeptical reception from the justices.
The 5-4 vote, with the court's four liberal members dissenting, was unprecedented — the Supreme Court had never before granted a request to halt a regulation before review by a federal appeals court.
"It's a stunning development," Jody Freeman, a Harvard law professor and former environmental legal counsel to the Obama administration, said in an email. She added that "the order certainly indicates a high degree of initial judicial skepticism from five justices on the court," and that the ruling would raise serious questions from nations that signed on to the landmark Paris climate change pact in December.
The White House said in a statement that it disagreed with the court's decision and remained confident that it would ultimately prevail.
"The administration will continue to take aggressive steps to make forward progress to reduce carbon emissions," it said.
Opponents of Obama's climate policy called the court's action historic.
"We are thrilled that the Supreme Court realized the rule's immediate impact and froze its implementation, protecting workers and saving countless dollars as our fight against its legality continues," said Patrick Morrisey, the attorney general of West Virginia, which has led the 29-state legal challenge.
The challenged regulation requires states to make major cuts to greenhouse gas pollution created by electric power plants. The plan could transform the nation's electricity system, cutting emissions from existing power plants by a third by 2030, from a 2005 baseline, by closing hundreds of heavily polluting coal-fired plants and increasing production of wind and solar power.