Case Info: Diamond Alternative Energy, LLC v. EPA | Case No. 24-7 | Date Argued: 04/23/25

Link to Docket: Here.

Background:

Section 209(a) of the Clean Air Act generally preempts States from adopting emission standards for new motor vehicles. 42 U.S.C. § 7543(a). But under Section 209(b) of that Act, EPA may grant California and only California-a waiver from federal preemption to set its own vehicle-emission standards. Before granting a preemption waiver, EPA must find that California "need[s]" its own emission standards "to meet compelling and extraordinary conditions." Id. § 7543(b)(1)(B).

In 2022, EPA granted California a waiver to set its own standards for greenhouse-gas emissions and to adopt a zero-emission-vehicle mandate, both expressly intended to address global climate change by reducing California vehicles' consumption of liquid fuel. Fuel producers challenged EPA's waiver as contrary to the text of Section 209(b). The D.C. Circuit rejected the challenge without reaching the merits, concluding that fuel producers' injuries were not redressable because they had not established that vacating EPA's waiver would have any effect on automakers.

Questions Presented:

1. Whether a party may establish the redressability component of Article III standing by relying on the coercive and predictable effects of regulation on third parties.
2. Whether EPA's preemption waiver for California's greenhouse-gas emission standards and zero-emission- vehicle mandate is unlawful.

Holding: The fuel producers have Article III standing to challenge EPA's approval of the California regulations.

Result: Reversed and remanded.

Voting Breakdown: 7-2. Justice Kavanaugh delivered the opinion of the Court, in which Chief Justice Roberts and Justices Thomas, Alito, Kagan, Gorsuch, and Barrett joined. Justice Sotomayor and Justice Jackson filed dissenting opinions.

Link to Opinion: Here.

Oral Advocates:

• For Petitioners: Jeffrey B. Wall
• For Federal Respondents: Edwin S. Kneedler, Deputy Solicitor General
• For State Respondents: Joshua A. Klein, Deputy Solicitor General, Oakland, Cal.