On December 15, 2015, the D.C. Circuit Court of Appeals refused to vacate EPA’s Mercury and Air Toxics Standards. The decision was not a surprise. As I noted earlier this fall, there is a definitely trend towards refusing to vacate complex EPA rules. Where the rule is sufficiently complicated and EPA can tell any kind of credible story that maintaining a slightly tarnished rule is better than no rule at all, or leaving an outdated rule in place, I think that vacatur is now more the exception than the norm.
What will happen in the long run remains uncertain. Judge Kavanaugh joined the decision, but he’s hardly a safe bet to affirm the MATS rule on the merits after EPA has finished addressing the cost/benefit concerns raised by the Supreme Court. Nonetheless, I still think that EPA should win.