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Ethan Shenkman is a partner in the Environmental Practice Group, where he represents a diverse array of clients in trial court and appellate matters, and in matters before federal and state agencies. He is nationally known for his work with climate change policy and regulation, representing clients in rulemakings and litigation concerning biofuels regulation, the Renewable Fuels Standard, phaseout of HFCs, the Clean Power Plan, NEPA and other climate-related litigation.

Mr. Shenkman brings more than 16 years of government experience to bear in guiding his clients through complex regulatory and enforcement challenges. He served for seven years as a political appointee in the Obama Administration, most recently as Deputy General Counsel at the US Environmental Protection Agency and, prior to that, as Deputy Assistant Attorney General at the US Department of Justice's Environment and Natural Resources Division. He previously served as a career attorney and litigator at DOJ.

During his post as Deputy General Counsel at the EPA, he was responsible for Clean Air Act regulations and litigation, cross-cutting administrative law issues, international environmental law, and Native American tribal affairs. He provided counsel for numerous key administration initiatives related to greenhouse gas pollution and climate change, international environmental agreements, free trade agreements, and tribal treaty rights.

In his role at DOJ, he managed a broad spectrum of litigation and policy initiatives, including supervising the Appellate Section, which handles appellate and Supreme Court cases across environment and natural resources law, and the Indian Resources Section. He represented more than a dozen federal agencies on environment and natural resources matters, ranging from NEPA to infrastructure and energy development to the Endangered Species Act.

Mr. Shenkman has extensive appellate and trial-level litigation experience. He has argued 24 cases in the US Circuit Courts of Appeal and the Alaska Supreme Court.


  • Major chemical manufacturer in enforcement proceeding before the Texas Council on Environmental Quality.
  • Major US retailer before DOJ with regard to plea agreement and compliance plan under federal environmental statutes.
  • Major renewable fuels manufacturer before EPA on regulatory issues under the Renewable Fuels Standard, and litigation concerning same.
  • Mining operation in defending against claims under multiple environmental statutes, including NEPA and Sections 401 and 404 of the Clean Water Act.
  • Amicus brief on behalf of outdoor recreation industry in support of petitioners challenging rescission of Clean Power Plan.
  • Foreign sovereign in international treaty arbitration arising from moratorium on mining operations.
  • Major pharmaceutical retailer in obtaining an injunction against tribal court jurisdiction in an opioid-related tort action.
  • The Hopi Indian Tribe in litigation over the Navajo Generating Station.


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The Legal 500 U.S.
"Leading Lawyers" Environment: Regulatory (2022-2023)
Environment: Regulatory (2018-2019, 2022)
Environment: Litigation (2018-2021)
Environment: Arbitration (2018)
Chambers USA
Environment (DC) (2022-2023)
Climate Change (Nationwide) (2023)
US Department of Justice John Marshall Award for Outstanding Achievement in Providing Legal Advice (2013)



  • J.D., University of Virginia School of Law, 1994, Order of the Coif, Editor-in-Chief, Virginia Law Review
  • B.A., Yale University, 1989, summa cum laude, Phi Beta Kappa


  • District of Columbia

Government & Military Service

  • Deputy General Counsel, US Environmental Protection Agency
  • Deputy Assistant Attorney General, US Department of Justice, Environment and Natural Resources Division
  • Counsel to the Assistant Attorney General, US Department of Justice, Environment and Natural Resources Division
  • Honors Attorney, Appellate Section and Law & Policy Section, US Department of Justice, Environment and Natural Resources Division
  • Bristow Fellow, Office of the Solicitor General, US Department of Justice


  • U.S. Court of Appeals for the Fourth Circuit, The Honorable Paul V. Niemeyer


  • Adjunct Professor of Environmental Law, Georgetown University Law Center
  • Member, Board of Directors, Environmental Law Institute