On the heels of the Supreme Court freezing one major U.S. EPA rule curbing power plant emissions, state challengers are pushing the justices to block another.

A coalition of 20 states yesterday asked Supreme Court Chief Justice John Roberts to stay an Obama administration rule cutting power plants' mercury emissions. The justices last year found that rule illegal, saying EPA had failed to properly consider costs, and they sent it back to a federal appeals court for further action.

The U.S. Court of Appeals for the District of Columbia Circuit in December rejected pleas to toss out the rule, deciding instead to send it back to EPA so the agency could tweak its cost analysis in light of the Supreme Court's 5-4 decision (Greenwire, Dec. 15, 2015).

EPA's Mercury and Air Toxics Standards, or MATS, has been ridiculed by states, industries and Republican lawmakers. Senate Majority Leader Mitch McConnell (R-Ky.) hailed the Supreme Court's rejection of the rule last year as a "cutting rebuke to the administration's callous attitude" about the impacts of its regulations.

If the high court doesn't block the rule now, the justices' decision in the mercury case "will be thwarted," the states warned in their petition yesterday. "Because this court's ruling means that EPA never acquired authority to impose this rule, this court should stay the unauthorized rule" pending a petition to the court asking that the rule be vacated in its entirety.


The states appear to have been emboldened by the justices' surprise decision earlier this month to step in and block the administration's Clean Power Plan, a rule to curb utilities' greenhouse gas emissions. Many lawyers speculated that the court's 5-4 decision to block that rule would spur a flood of similar requests to the high court.

In their request that Roberts block the mercury rule, the states pointed to the stay of the Clean Power Plan. "Just two weeks ago this Court correctly granted a stay of an EPA rule ... before the rule had undergone judicial review, presumably because this court recognized that there was a strong likelihood that the rule was likely to be held to be unlawful and in excess of the agency's authority under the Clean Air Act."

A stay is "even more warranted here, after this Court has reviewed EPA's finding authorizing the Mercury Rule and has found it to be unlawful and in excess of EPA's authority under that same Act," the petition added.

The state challengers are Alabama, Alaska, Arizona, Arkansas, Idaho, Iowa, Kansas, Kentucky, Michigan, Mississippi, Missouri, Nebraska, North Dakota, Ohio, Oklahoma, South Carolina, Texas, Utah, West Virginia and Wyoming.

The states' request was sent to Roberts, who handles such applications for decisions made by the D.C. Circuit. He can unilaterally decide how to handle the issue or refer it to the full court for a decision. In the case of the Clean Power Plan, all nine justices weighed in.

If Roberts were to act alone, parties could later appeal his decision to the court's other justices.

The death of Justice Antonin Scalia earlier this month could hurt states' chances of getting a stay from the Supreme Court. The conservative justice penned the majority decision rejecting the mercury rule, and was also the fifth vote to stay the Clean Power Plan. Only eight justices are on the bench for at least the near term, so if the court's liberal wing were to oppose the stay, the conservative branch wouldn't be able to get the fifth vote needed to secure a majority of the full court.

The rule, issued by EPA in December 2011, requires coal-burning power plants to reduce emissions of mercury, lead, arsenic and other hazardous air pollutants. Coal plants are the country's largest emitters of mercury, and EPA said the standards would prevent 11,000 premature deaths a year and yield up to $90 billion in health benefits. The rule was expected to cost $9.6 billion per year.

Earthjustice attorney James Pew called the states' stay request "premature and wrongheaded." He also said, "The Supreme Court chose not to stop the rule but, instead, to require EPA to explain it. The agency should be given a chance to comply with the Supreme Court's order." He added, "EPA's limits on toxic pollution from electric power plants in the Mercury and Air Toxics rule are already saving thousands of lives every year."

Click here to read the petition.