Peg has served as first chair trial and appellate counsel in state and federal courts in over 30 jurisdictions. Her work has spanned antitrust, commercial, class action, environmental, insurance, mass tort, product liability and reinsurance disputes. Peg has taken numerous cases to verdict/judgment before juries, judges and arbitration tribunals. Many of her cases have involved high-profile public policy issues from the Agent Orange litigation in the 1980s, environmental and Superfund litigation involving such notorious sites as Love Canal and the Hudson River in the 1990s, to sexual abuse, 9/11, antitrust and ERISA litigation in the 21st Century.

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  • Lead trial counsel for defendant fiduciaries in eight day ERISA class action bench trial. Obtained rulings denying all injunctive relief and 97% of damages sought
  • Lead trial counsel for defendant hospital system defeating governmental effort to enjoin hospital closure
  • Lead trial counsel for plaintiff trade association in a two-week federal jury trial involving a nationwide retirement program for municipal workers. Verdict returned for client on all counts.  Summary affirmance in D.C. Circuit

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  • Benchmark Litigation 2020
  • Benchmark Litigation National 2020, Litigation Star, Top 250 Women in Litigation
  • The Best Lawyers in America 2008 to 2021, Litigation – Insurance, Commercial Litigation, Insurance Law and Litigation – Environmental

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University of Notre Dame, JD, 1981
St. Lawrence University, BA, cum laude, 1978

District of Columbia

US Supreme Court
US Court of Appeals for the Federal Circuit

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Margaret H. Warner

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