Litigation Update: Ohio v. Environmental Protection Agency

A Regulatory Transparency Project Webinar

Event Video

The EPA has rescinded The Safer Affordable Fuel Efficient Vehicles Rule Part One: One National Program rule.  It has reinstated a waiver of Clean Air Act (CAA) preemption for California’s greenhouse gas standards and Zero Emission Vehicle sales mandate.  These are some facets to California’s Advanced Clean Car Program.  

In Ohio v. EPA, now pending before the D.C. Circuit, various industry and state petitioners have challenged EPA’s reinstatement of the waiver as preempted by the CAA; and have argued that Congress has not implicitly authorized it either.  Numerous amici have weighed in on this issue as well.  The D.C. Circuit soon will hear oral argument in this case, which eventually might make it to the Supreme Court.  

Raised by some amici, one of the pertinent issues here is that the federal government is showing favoritism to California in contravention of the Constitution’s equal-sovereignty principle, which the Supreme Court has recognized in a long line of cases (most recently culminating in Shelby County v. Holder).

This litigation update will feature a vital discussion from the eminent Jonathan Brightbill, who served as Acting Assistant Attorney General of the United States (leading the Justice Department’s Environment and Natural Resources Division, where he worked on the Trump Administration’s One National Standards Rule), and who currently is a partner at Winston & Strawn LLP; Robert Percival, the Robert F. Stanton Professor of Law and the Director of the Environmental Program at the University of Maryland School of Law; and Sohan Dasgupta, who served as the Deputy General Counsel of the U.S. Department of Homeland Security and who is a partner at Taft LLP.


  • Jonathan Brightbill, Partner, Winston & Strawn LLP
  • Robert Percival, Robert F. Stanton Professor of Law, University of Maryland Carey School of Law
  • [Moderator] Sohan Dasgupta, Partner, Taft Stettinius & Hollister LLP

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As always, the Federalist Society takes no position on particular legal or public policy issues; all expressions of opinion are those of the speaker.