Daniel W. Nelson Washington, D.C.
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Peter E. Seley Washington, D.C.
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The Environmental Litigation and Mass Tort Practice Group has extensive experience representing diverse clients in matters involving U.S. state and federal clean air laws.  The group has familiarity with matters involving greenhouse gas emissions, climate change enforcement actions under the U.S. Clean Air Act's Prevention of Significant Deterioration, and New Source Review provisions.   

No law firm in the country is more involved in the area of climate change litigation than Gibson, Dunn & Crutcher. Our participation in several groundbreaking matters led to Gibson Dunn's inclusion in Chambers' initial climate change practice rankings.  

Drawing on this experience, we counsel clients in various industries concerning the impact of greenhouse gas legislation, litigation and regulatory initiatives on their businesses.  We anticipate that the U.S. Congress, Environmental Protection Agency and Department of Transportation, as well as other federal and state agencies, will continue to consider various proposals to reduce the emissions of greenhouse gases from sources in multiple sectors of the economy.  As that occurs, Gibson Dunn will continue to be at the forefront of this important field.  


The Environmental Litigation and Mass Tort group represents clients in matters involving U.S. state and federal clean air laws and all matters concerning climate change. 

Recent representations include: 

  • Defended automobile manufacturers against a lawsuit by the State of California claiming that greenhouse gas emissions from their vehicles constitute a public and private nuisance by causing global warming and seeking billions of dollars in damages.  We successfully moved to dismiss that case on the ground that limiting greenhouse gas emissions is not a matter for the courts to decide under tort law, but rather constitutes a political question best left to the elected branches of government. 
  • Represented a coalition of automakers, engine manufacturers and auto dealers before the U.S. Supreme Court in the seminal case involving EPA's authority to regulate greenhouse gas emissions from automobiles under the Clean Air Act.
  • Representing the Association of International Automobile Manufacturers (AIAM) in multiple challenges to state regulations limiting greenhouse gas emissions from motor vehicles. 
  • Submitted comments to the EPA on behalf of automobile manufacturers in opposition to the State of California's request for a pre-emption waiver under Section 209(b) of the Clean Air Act for its motor vehicle greenhouse gas regulations.  After the EPA denied the request and the State brought a challenge, Gibson Dunn successfully moved to intervene to uphold the determination.