Reuters reports that “the U.S. Supreme Court on Tuesday agreed to weigh a challenge by industry groups and some states to an Obama administration regulation intended to limit emissions of mercury and other hazardous pollutants mainly from coal-fired power plants.”  

“In a blow to the federal government, the justices said in a brief order that they would review an April ruling by the U.S. Court of Appeals for the District of Columbia Circuit that upheld the rule.”  

“The court order said the justices would focus on the single question of whether the U.S. Environmental Protection Agency ‘unreasonably refused to consider costs in determining whether it is appropriate to regulate hazardous air pollutants emitted by electric utilities.’”