David G. Tewksbury - McDermott Will & Emery


David G. Tewksbury focuses his practice on federal energy regulatory law, particularly as it relates to electric power. He advises independent power producers, power marketers, trade associations and others on a wide range of federal energy regulatory, markets and reliability matters.

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  • Represented the Electric Power Supply Association (EPSA) and others before FERC in successfully opposing DOE-proposed rule to subsidize uneconomic coal-fired and nuclear-powered generation resources*
  • Represented Clearway Energy in obtaining blanket authorization for drop-downs of interests in FERC-regulated public utilities from parent to yieldco*
  • Represented IPP complainants and others in successful complaint to FERC seeking expansion of offer-floor mitigation for subsidized resources participating in PJM capacity market*

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  • The Best Lawyers in America, Energy Law and Energy Regulatory Law, 2022-2024
  • Chambers USA
    • Energy: Electricity (Regulatory & Litigation) – Nationwide, Band 1, 2016-2023
    • Energy: Electricity (Regulatory & Litigation) – Nationwide, Leading Lawyer, 2009-2020
  • Chambers Global
    • Energy: Electricity (Regulatory & Litigation) – USA, Band 1, 2017-2020
    • Energy: Electricity (Regulatory & Litigation) – USA, Leading Lawyer, 2012-2020
  • The Legal 500 US, Leading Lawyer in Energy Regulation: Conventional Power and Energy Regulation: Electric Power, 2020-2023

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Washington and Lee University, JD, magna cum laude, Order of the Coif, 1998
Williams College, BA, 1989

US Supreme Court
US Court of Appeals for the District of Columbia
US Court of Appeals for the Third Circuit
US Court of Appeals for the Fourth Circuit
US Court of Appeals for Seventh Circuit
US Court of Appeals for the Ninth Circuit

District of Columbia