Diamond Alternative Energy, LLC v. EPA

Majority reasoning

The majority held that the fuel producers' injury and causation were straightforward and undisputed: the California regulations are explicitly designed to reduce gasoline consumption, which directly cuts into the fuel producers' revenue. On redressability — whether a court ruling in the fuel producers' favor would actually fix their injury — the Court reasoned that basic economic logic and the record evidence both show that striking down the regulations would likely lead automakers to produce more gasoline-powered vehicles and fewer electric ones, increasing fuel sales. The Court pointed to California's own estimates projecting billions of dollars in reduced gasoline demand, California's expert declarations stating that without the rules fewer electric vehicles would be sold, EPA's repeated affirmations that California "needs" the standards, and five automakers' own prediction that rivals would shift back toward gasoline-powered cars if the rules were removed. The majority rejected the argument that the fuel producers needed to submit affidavits from economists or automakers, reasoning that requiring such evidence would make standing dependent on whether regulated third parties are willing to publicly oppose the government — a rule that would unfairly close courthouse doors to many legitimate challenges to agency action. Finally, the Court dismissed the idea that the electric-vehicle market had permanently changed to the point where the regulations no longer matter, noting that governments do not typically keep enforcing rules that have no effect, and that complex markets shift over time in ways courts cannot predict with certainty.

Dissent reasoning

Justice Sotomayor argued that the Court should not have used this case to broadly address standing law at all, because the D.C. Circuit's ruling rested primarily on a factual mistake — it incorrectly believed both components of California's program expired after model year 2025, when in fact only the electric-vehicle mandate does. In her view, the right remedy was simply to send the case back to the D.C. Circuit to redo its redressability analysis with the correct timeline, rather than for the Supreme Court to conduct that analysis itself. Justice Jackson wrote separately to raise two broader concerns. First, she argued the Court should have denied review entirely, or at least held the case in abeyance, because the dispute is nearly moot: the electric-vehicle mandate sunsets with model year 2025, and EPA under the current administration is widely expected to withdraw the waiver entirely. Second, and more fundamentally, Justice Jackson argued that the majority's willingness to rely on "commonsense" economic inferences to find redressability for the fuel industry stands in sharp contrast to cases where the Court refused to draw similar commonsense inferences for less powerful plaintiffs — citing cases where low-income housing seekers, Black parents challenging school segregation, and civil liberties groups challenging surveillance were denied standing under stricter redressability standards. She argued this inconsistency risks the appearance that the Court applies standing doctrine more generously to corporate and industry litigants than to ordinary citizens, undermining public confidence in the Court's impartiality.