President Obama prophesied at the United Nations last week that climate change is the “one issue that will define the contours of this century more dramatically than any other,” and perhaps this vision of Apocalypse explains why he thinks he can disregard the law to regulate carbon. Whatever they think about warming, the courts may pay more respect to statutes.

This month a three-judge panel of the D.C. Circuit Court of Appeals agreed to hear a challenge to the Environmental Protection Agency’s new climate rules under the Clean Air Act. The order was unusual because the courts generally review rules only after they are finalized, which could take another year or more. The Ohio-based coal company Murray Energy and a dozen states are suing under the All Writs Act of 1789.

Murray drew a D.C. Circuit panel including a liberal (Judge Sri Srinivasan ), a moderate (Judge Thomas Griffith ) and a conservative (senior Judge Douglas Ginsburg ). Murray also happens to be correct on the legal merits.

The EPA wants to reorganize U.S. electric power generation and drive coal and eventually natural gas out of the energy mix under a rarely used backwater of the Clean Air Act called section 111(d), whose mandates apply state by state. The problem is that the law also includes a clause meant to prevent double regulation: Air pollutants that are controlled at the national level under the act’s section 112 are therefore specifically excluded from section 111 control. Carbon emissions, under a separate 2012 rule, are already subject to 112, but the EPA wants to have it both ways.

In a legal memorandum, the EPA claims that “a literal reading of that language would mean that the EPA could not regulate any air pollutant from a source category regulated under section 112,” and thus such a reading is “not reasonable.” In other words, obeying the law would not let the agency do what it wants to do, so the law must go.

Murray is seeking a writ of mandamus, a type of injunction the courts only grant when the government has taken an extraordinary action beyond its statutory authority. Such relief is appropriate here because states and utilities are already spending billions of dollars to start to comply with EPA dictates long before the rule-making is finished. Nor is there any benefit to waiting, because the suit challenges not this or that detail but the agency’s underlying legal authority.

The D.C. Circuit already tossed one EPA rule in 2008 for ignoring the distinction between Clean Air Act sections 111 and 112, and the Supreme Court distinguished national and state-by-state standards in the 2011 American Electric Power v. Connecticut decision. The courts seem increasingly alarmed by abuses of executive power, especially in environmental law, so Murray Energy v. EPA is a good opportunity for the D.C. Circuit to define the contours of Mr. Obama’s Presidency.