Supreme Court Justice Antonin Scalia is being chided by legal experts for making a major error in his latest dissent. Talking Points Memo reported that Scalia was dissenting to a 6-to-2 ruling in EPA v. Homer City Generation, upholding the Environmental Protection Agency's authority to regulate air pollution from coal across state lines.

The arch conservative jurist wrote that the majority's decision runs counter to a unanimous ruling by the court in 2001, mistakenly claiming that the court struck down the agency's ability to override cost considerations when setting regulations.

TPM's Sahil Kapur quoted the dissent, "This is not the first time EPA has sought to convert the Clean Air Act into a mandate for cost-effective regulation. Whitman v. American Trucking Assns., Inc., 531 U. S. 457 (2001), confronted EPA's contention that it could consider costs in setting [National Ambient Air Quality Standards]."

The dissent -- in which Scalia was joined by fellow right-leaning justice Clarence Thomas -- was factually inaccurate, however, because the EPA was actually arguing the opposite in the 2001 case. The agency argued that the benefits to the population of reducing coal-generated air pollution outweigh considerations of cost. It was the trucking industry that argued that curbing pollution poses an undue economic burden on polluters.

The author of that unanimous 2001 decision was, in fact, Scalia. University of California-Berkeley professor Dan Farber wrote on Tuesday that Scalia's blunder is "embarrassing" and "cringeworthy."

At the environmental law and policy blog Legal Planet, Farber said, "Scalia’s dissent also contains a hugely embarrassing mistake. He refers to the Court’s earlier decision in American Trucking as involving an effort by EPA to smuggle cost considerations into the statute. But that’s exactly backwards: it was industry that argued for cost considerations and EPA that resisted. This gaffe is doubly embarrassing because Scalia wrote the opinion in the case, so he should surely remember which side won! Either some law clerk made the mistake and Scalia failed to read his own dissent carefully enough, or he simply forgot the basics of the earlier case and his clerks failed to correct him. Either way, it's a cringeworthy blunder."

Adam Serwer said at MSNBC that the blunder is particularly galling for the justice in that his dissent was dripping with contempt for the majority's decision.

The decision, Scalia said, “feeds the uncontrolled growth of the administrative state at the expense of government by the people" and that it amounted to an "undemocratic revision" of the Bush-era Clean Air Act. Bristling with sarcastic asides, Tuesday's dissent said that for the EPA to nullify cost as a consideration in its efforts to curb air pollution amounts to a Marxist ideal of "from each according to his ability."

Doug Kendall of the Constitutional Accountability Center said on Tuesday that Scalia's blunder is highly unusual and downright baffling.

"It is a mind-blowing misstatement of a basic fact of the American Trucking Association ruling which Justice Scalia himself wrote. And it's not just a stray passage -- it's the basis for an entire section of the dissent," said Kendall. "It is very unusual for to see a passage that so clearly misstates the fundamental facts of a prior ruling, especially one written by the justice himself."

The dissent's error, said Serwer, has since been corrected.

Read Tuesday's decision by the Court and Scalia's dissent, embedded below via Scribd:

EPA v. Homer

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