The Nickel Report

On June 18, 2025, the Supreme Court decided Oklahoma v. EPA and EPA v. Calumet, a pair of cases that focus on the Clean Air Act’s (CAA or Act) venue selection provisions.

The judicial review provisions of the Act send review of “nationally applicable” EPA actions to the DC Circuit and review of “locally or regionally applicable” EPA actions to the regional circuits. See 42 U.S.C. § 7607(b)(1). However, in an exception to that rule, venue may lie in the DC Circuit for regionally applicable actions that are “based on a determination of nationwide scope or effect.” In the Court’s two recent decisions, it explained that the CAA venue analysis called for a two-step inquiry. First, courts must decide whether the EPA action is nationally applicable or only locally or regionally applicable; if nationally applicable, the case belongs in the DC Circuit. Second, if locally or regionally applicable, courts must decide whether the case falls within the exception for “nationwide scope or effect” to override the default rule of regional circuit review.

EPA has finalized a regulation you can live with, but someone dissatisfied with that result has sued the Agency.  Should you intervene to defend EPA’s action?  Is it worth it?  Does the court really pay attention to the arguments of an intervenor?  A recent decision by the D.C. Circuit in Masias v. EPA, No. 16-1314 (D.C. Cir. Oct. 19, 2018), illustrates the value of participation as a Respondent-Intervenor in these circumstances.