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Thomasina A. Dumonceau

P: 416-593-2999
F: 416-594-3527
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  • Called to the Bar of Ontario, 2002
  • LL.B., University of Toronto, 2000
  • B.A., (Honours) International Studies, University of Saskatchewan, 1997
Thomasina Dumonceau Photo ©2021 Blaney McMurtry LLP

For over fifteen years, clients have relied on Thomasina’s strong analytical skills and pragmatic approach to litigation to achieve favourable results in a cost-effective manner. Known for her attention to detail and her ability to drill down to the essential facts and issues of a case, Thomasina has experience handling complex, multi-party claims.

Thomasina’s litigation practice focuses on defending professionals in malpractice or errors and omission claims, including financial advisors, appraisers, lawyers, engineers, insurance and mortgage brokers, property managers, construction monitors and various health care professionals (massage therapists, physiotherapists, speech pathologists, social workers and nurses to name a few).

Beyond her expertise with professional liability claims, Thomasina also handles construction and environmental claims and has experience with a wide variety of commercial and general liability claims, as well as with life and disability claims. She has also represented directors and officers on insured D&O claims.

Thomasina’s practice also includes representing various health professionals in professional regulation matters, including College complaints, investigations, and registration appeals, as well as representing financial advisors in FSCO and MFDA proceedings.

Thomasina has experience acting for insurers, individuals, corporations and a variety of social agencies and public authorities and institutions.

An active advocate, Thomasina has defended claims throughout Ontario and has appeared before the Superior Court of Justice, the Ontario Divisional Court, the Ontario Court of Appeal, as well as before multiple regulatory bodies and professional Colleges.

  • LL.B., University of Toronto, 2000
  • B.A., (Honours) International Studies, University of Saskatchewan, 1997
 Practice Areas  Called to the Bar
  • Called to the Bar of Ontario, 2002




  • Law Society of Ontario
  • Ontario Bar Association
  • Professional Liability Underwriting Society
  • Canadian Defence Lawyers

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