Mary Bonacorsi’s 40-year career has been built on representing major corporations in high-stakes trials and arbitrations.
Mary advises clients on complex disputes of all types, including general commercial litigation defense, real estate and construction claims, labor and employment matters, banking, and railroad real estate. She has tried, as lead counsel, more than 75 jury and non-jury cases to conclusion and is a member of the American Board of Trial Advocates.
A key player in some of the longest and most complex trials in the St. Louis region, Mary developed excellent relationships with judges and opposing counsel. She has often been asked to join pending cases when parties need an experienced courtroom litigator since she excels at leading trial teams, crafting trial strategy, and coordinating the many moving parts of litigation. Mary is a gifted story-teller, supporting cases through skillful cross-examination of opposing witnesses.
Mary was one of the first women litigators in St. Louis and a founder of Thompson Coburn’s Total Commitment® Women’s Initiative. In 2015, Mary’s role as a mentor and business leader was recognized by the YWCA of Metro St. Louis with a 2015 Leader of Distinction award. She is also a Life Fellow of the American Bar Foundation.
experience
- Served on the trial team that defended a regional beverage distributor sued after it challenged a 100-year-old state regulation governing relationships between suppliers and distributers. The case, which raised significant questions about state franchise law, was successfully settled a week into a jury trial.
- Successfully tried a case for an Illinois school board in a federal jury trial over an age discrimination suit.
- Successfully negotiated a settlement that resolved a dozen lawsuits between multiple railroads and the Illinois Department of Transportation over railroad property taken for the construction of the Stan Musial Veterans Memorial Bridge and related highway projects.
- Obtained a judgment for a major banking institution that spared it from making multimillion dollar capital contributions to a large apartment development financed through federal historic tax credits. The same ruling also allowed the bank to sell its limited partnership interests without liability for additional contributions or guaranties.
- In a case of national importance, succeeded in obtaining a temporary restraining order for a major regional transit authority in an action to stop collection of a $40 million-plus payment resulting from the downgrade of investment ratings for AIG, which had provided credit support to the transit agency. The action was the lead case in the nation and watched by municipalities in the U.S. and banks around the world that were equity investors in AIG-backed transactions. The aggregate potential liabilities were over $300 million for the transit agency. Prior to a formal ruling, negotiations between both parties resulted in a private settlement.
- Prevailed on summary judgment in Cole County in a case brought by the Missouri Attorney General’s Office against a railroad client over the railroad’s plans to dismantle an abandoned bridge and use the steel for construction of a new bridge. The ruling was affirmed by the Western District Court of Appeals, and Mary also represented the railroad before the Clean Water Commission, which upheld issuance of a DNR permit for the project.
Professional
- American Board of Trial Advocates
- American Bar Association, Litigation, Labor & Employment, and Probate and Real Property Sections
- Theodore McMillian American Inn of Court, Master of the Bench
- Missouri Bar Association
- The Bar Association of Metropolitan St. Louis
- Illinois Bar Association
- The American Bar Foundation, Fellow
- Federal Practice Committee of Eastern District of Missouri, Member and Chairperson, 1988-present
- Committee for Eighth Circuit Judicial Conference, Member, Attorney Admission Fee Fund Committee
- Federal Magistrate Selection Panel, 1991, 2015
Community
- Boys and Girls Clubs of Greater St. Louis
- Board Member, 2008-Present
- Board of Directors, Secretary to the Board, Board of Directors, Vice Chair, and Chair, 2016-2018
- Judicial Learning Center
- Board of Directors, Secretary, 2008-Present
- The Salvation Army
- Chair, Property Committee, 1998-present
- Executive Committee, 1996-Present
- Chairperson, 2000-2002
- Vice Chair, 1998-2000
- Treasurer, 1996-1998
- Chair, Finance Committee, 1996-1998
- Lutheran Family & Children’s Services Public Relations Committee to Advisory Board
- Mentor St. Louis, Board Member, Vice Chair
- United Way of Greater St. Louis, Consultant, Court Appointed Special Advocates
- The Best Lawyers in America (by BL Rankings) for Eminent Domain, 2007-2024
- Missouri & Kansas Super Lawyers (by Thomson Reuters), 2005-2019
- Top 50 Women, 2005, 2008-2012
- Top 100 for Missouri & Kansas, 2010-2011
- Top 50 in St. Louis, 2010-2011
- YWCA of Metro St. Louis – Leader of Distinction, 2015
- Super Lawyers (by Thomson Reuters) Corporate Counsel, 2008-2014
- Co-Author, “Strategies for Documenting Vessel Acquisition and Financing Transactions”
The St. Louis Bar Journal, Vol. 63, No. 4; Winter 2016 - Author, “Alive, But Not Quite Kicking: Circuit Split Illustrates the Progressive Deterioration of the D’Oench, Duhme Doctrine”
Saint Louis University Law Journal, Vol. 42, No. 3, 1998
- Speaker, “Regulation O: Loans to Insiders”
Lorman Education Services, Essentials of Banking Law: An Overview of the Legal Issues in the Banking Industry in Missouri - Speaker, “Dodd-Frank Act– Transactions with Affiliates and Insiders”
Dodd-Frank Act– A Practical Overview for Bankers, Thompson Coburn LLP, September 30, 2010