In her 37-year career, 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 and antitrust litigation in the 21st Century.

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  • 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
  • Lead trial counsel for plaintiff insurer in six-week jury trial involving Superfund, asbestos and corporate succession liability. Verdict achieved recovery of tens of millions of dollars in contribution action related to liability evolving over the next two decades

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  • Benchmark Litigation
  • Benchmark Litigation National, Litigation Star, Top 250 Women in Litigation
  • The Best Lawyers in America 2008 to 2019, 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

Courts / Agencies
Supreme Court of the United States
US Court of Appeals for the Federal Circuit

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Margaret H. Warner

Insights & Events / Media

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