Helliker

This case involves a challenge under § 304 of the Clean Air Act (“CAA”), see 42 U.S.C. § 7604 (a), known as the citizen suit provision. A coalition of community organizations (“El Comité”) brought suit against California state officials (“California”) responsible for designing and implementing a state air quality plan. The complicated approval process for the State Implementation Plan (“SIP”) required much back-and-forth between California and the Environmental Protection Agency (“EPA”). El Comité takes issue with both the process by which California obtained EPA approval of the SIP and the final outcome of that approval process. In particular, El Comité argues that California violated federal law by failing to adhere to the SIP approved by the EPA, which it argues required California to implement additional regulations in five areas where air quality standards for reducing harmful emissions have not been met. California went astray, according to El Comité, by using the wrong data to calculate the baseline for its emission standards and by ignoring deadlines that were intended to be incorporated into EPA’s final approval of the SIP. El Comité’s claim turns on…