Overview
Margaret (Peg) Warner has served as first chair trial and appellate counsel in state and federal courts in over thirty jurisdictions. Her work has spanned antitrust, commercial, class action, environmental, healthcare, insurance, mass tort, product liability, and reinsurance disputes. As lead trial counsel, Peg has taken over fifty 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, healthcare, ERISA and COVID-19 litigation in the 21st Century.
Peg is recognized as a leading national trial lawyer in a number of highly regarded legal directories and industry publications. She has been described as “an intimidating figure” “knowledgeable, assertive and in tune with clients’ needs.” She “excels at complex litigation and arbitration” and “has a reputation for being a hard-nosed, no nonsense and smart litigator.”
She has counseled numerous senior executives and boards of insurance entities on an array of business opportunities and exposures.
Peg and her team received The Financial Times 2012 US Innovative Lawyers Award for work resolving 9/11 litigation. She formerly led McDermott’s global controversies practices and served on the Executive and Management Committees.
Results
- 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. Full affirmance in Tenth Circuit
- Lead trial counsel for plaintiffs in multi-phased bench trials lasting months on more than thirty statutory and common law issues involving insurance coverage for long-tailed claims. Won almost all issues tried
- Lead trial counsel obtaining dismissal of ERISA claims against fiduciaries in putative class action litigation. Full affirmance in Ninth Circuit
- Lead arbitration counsel for petitioner in reinsurance dispute relating to fraudulent reserving practices. Obtained eight figure award
- Lead trial counsel for defendants in employment actions involving executive termination. Settled favorably during trials
- Lead trial counsel for defendant healthcare system defeating governmental effort to enjoin hospital closure; representation of healthcare systems in numerous contractual and regulatory disputes nationwide
- Lead trial counsel for plaintiff trade association in two-week federal jury trial involving a nationwide retirement program for municipal workers. Verdict returned for client on all counts. Summary affirmance in DC Circuit
- 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 three decades. Unanimous win in Oregon Supreme Court
- Lead trial counsel for plaintiff in complex bench trial involving proof of existence and terms of over thirty contracts dating back to the 1950s. Judgment won as to all contracts
- Lead counsel in trial court and 6th Circuit obtaining order compelling arbitration of dispute relating to insurance company formed pursuant to the Affordable Care Act. Favorable resolution of subsequent arbitration
- Lead arbitration counsel for respondent in two international arbitration hearings addressing $150 million long-term transportation contracts in the Northeast Corridor. Awards totally vindicated client’s position and thwarted petitioners’ monetary and commercial allegations
- Lead counsel who conceived, negotiated and secured S.D. NY approval of the landmark settlement of more than 10,000 mass tort cases against the City of New York and scores of private contractors that undertook rescue, recovery, and debris removal operations after the 9/11 terrorist attack. The settlement’s ninety-six percent acceptance rate is the highest in any mass tort settlement of this size. Briefed, argued and won two Second Circuit appeals on provisions of the settlement
- Lead defense counsel in antitrust cases involving merger challenges, price-fixing and private class actions
- Lead insurance counsel who conceived and negotiated the settlement of more than 600 sexual abuse cases involving the Roman Catholic Church in California. Additional experience nationwide in numerous sexual abuse cases spanning allegations from the 1950s through the present
- Lead trial and appellate counsel for plaintiff/appellee who secured over $238 million recovery relating to 9/11 terrorist attack
- National coordinating counsel for major property and casualty insurers for environmental, mass tort, medical device, sexual abuse, and COVID-19 claim
Recognitions
- Benchmark Litigation National, Litigation Star, Top 250 Women in Litigation
- Best Lawyers in America, Commercial Litigation (2008-2024 and 2026), Insurance Law (2008-2024 and 2026), Litigation – Insurance, 2021-2026
- Business Insurance 2008, named one of its 25 international Women to Watch
- Chambers National Insurance Dispute Resolution – Insurer, District of Columbia Band 1
- Chambers USA, Insurance: Dispute Resolution: Insurer, 2021 and 2022, Insurance: Insurer, 2020-2023
- Legal 500 US, Hall of Fame, 2021-2023
- Super Lawyers
Credentials
Education
University of Notre Dame, JD
St. Lawrence University, BA, cum laude
Admissions
District of Columbia
Courts/Agencies
US Supreme Court
US Court of Appeals for the Federal Circuit
US Court of Appeals for the District of Columbia Circuit
US Court of Appeals for the Second Circuit
US Court of Appeals for the Third Circuit
US Court of Appeals for the Fifth Circuit
US Court of Appeals for the Sixth Circuit
US Court of Appeals for the Seventh Circuit
US Court of Appeals for the Ninth Circuit
US Court of Appeals for the Tenth Circuit
District of Columbia Court of Appeals
