Toronto’s leading professional liability lawyers

These are the leading Toronto-based professional liability lawyers based on Lexpert’s annual peer survey

These are the leading Toronto-based professional liability lawyers based on Lexpert’s annual peer survey. The complete list of Ontario’s most recommended professional liability lawyers and law firms can be accessed via our practice area rankings.

In our survey, professional liability practice covers the provision of advice and representation in civil proceedings alleging damages resulting from the negligent provision of professional services. The scope of this area encompasses different professionals, including lawyers, notaries, insurance agents and brokers, real estate professionals, accountants, architects and engineers, directors and officers, actuaries and stockbrokers. Lexpert has a separate survey for medical negligence.

Most frequently recommended professional liability lawyers

Sarit E. Batner

Law firm: McCarthy Tétrault LLP


Year called to the Bar: 2000

Sarit E. Batner is a partner at McCarthy Tétrault LLP, where she is also a member of the board of partners. She practices trial and appellate litigation and arbitration at all levels of Canadian courts, with a focus on complex commercial litigation. Batner boasts extensive experience as lead counsel in cases involving shareholders’ rights, professional negligence, breaches of fiduciary duties, breaches of contract and taxation. She acts in wide variety of proceedings for physicians, engineers, accountants and lawyers. Batner is a frequent writer and speaker on matters of substantive law, trial and appellate advocacy, and issues affecting women and young professionals.

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Tom Curry

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1986

Tom Curry is the managing partner at Lenczner Slaght Royce Smith Griffin LLP. He is recognized as one of the most experienced trial and appellate advocates in Canada. Curry has a long record of success in high-profile commercial litigation, class actions, arbitrations, business disputes, administrative law, judicial review, intellectual property, competition and professional liability cases. He is a regular speaker on a wide variety of subjects relating to trial practice and substantive law. Curry was recently a recipient of the prestigious Law Society Medal for his exceptional career achievement and exemplary contribution to the profession.

Brian J. Gover

Law firm: Stockwoods LLP


Year called to the Bar: 1983

Brian J. Gover serves as a partner at Stockwoods LLP. He has extensive experience in both federal and provincial commissions of inquiry and related processes. His clients include individuals, corporations, regulators and government agencies. Gover is a former executive legal officer to Ontario’s Superior Court of Justice. He is regularly retained to act for judges facing disciplinary proceedings. Since 2013, Gover has assisted the judges tasked with administering the Indian Residential Schools Settlement Agreement, Canada's largest and most complex class action settlement. His extensive teaching experience includes serving as an adjunct professor at Western and Osgoode Hall Law School. Gover is a fellow of the American College of Trial Lawyers, a fellow and director of the International Academy of Trial Lawyers and was president of The Advocates’ Society from 2018 to 2019.

Peter Griffin

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1980

Peter Griffin is a founding partner at Lenczner Slaght Royce Smith Griffin LLP. He boasts extensive experience in complex cross-border litigation, especially as it relates to class proceedings and insolvency and restructuring. Griffin regularly advises the boards of national and multinational companies. He also represents clients in arbitration and alternative dispute resolution proceedings and acts as an arbitrator in commercial disputes. Griffin is constantly sought out as an expert speaker on advocacy, shareholder disputes, class actions, professional liability and insolvency and restructuring.

Consistently recommended professional liability lawyers

John Adair

Law firm: Adair Goldblatt Bieber LLP


Year called to the Bar: 2006

John Adair is a partner at Adair Goldblatt Bieber LLP. He devotes his practice to commercial litigation, with a focus on partnership, contractual and estate disputes. Adair regularly represents clients in directors’ and officers’ liability claims, enforcement of foreign judgments and professional liability matters. He has also written and spoken on numerous occasions on advocacy-related topics and has won numerous awards for his written articles. Adair previously taught trial advocacy at both the University of Toronto and Osgoode Hall Law School.

William D. Black

Law firm: McCarthy Tétrault LLP


Year called to the Bar: 1989

William D. Black is partner at McCarthy Tétrault LLP’s Toronto office. He specializes in civil litigation, with an emphasis on professional negligence and commercial litigation. Black also focuses on the conduct of trials and appeals in civil cases and before administrative tribunals. He has extensive experience in professional liability claims and proceedings in the areas of engineering, medicine, accounting and mining. Black also boasts extensive trial and appellate work representing physicians in medical malpractice claims and before the College of Physicians and Surgeons of Ontario. He has prosecuted matters for the Association of Professional Engineers for 15 years and continues to be involved in various civil actions involving various engineering issues.

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Sheila R. Block

Law firm: Torys LLP


Year called to the Bar: 1974

Sheila R. Block is a partner and the chair of the litigation and dispute resolution practice at Torys LLP. She is also a senior trial and appellate counsel with a broad civil litigation practice, which includes corporate, commercial and securities litigation, intellectual property, defamation and administrative law cases. Block has appeared as counsel on a wide range of cases before all levels of court in Canada and in international arbitrations and other tribunals. She has also taught advocacy in Canada, the US, England, Scotland, New Zealand and El Salvador.

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Nina Bombier

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1999

Nina Bombier is a partner at Lenczner Slaght Royce Smith Griffin LLP. Her litigation practice encompasses commercial litigation, professional negligence and regulatory matters, insurance litigation and public law. She has extensive trial experience in complex commercial and regulatory cases, in addition to many medical malpractice actions. Bombier has appeared as counsel before all levels of court in Ontario, the Federal Court and the Supreme Court of Canada. She also appears regularly before administrative tribunals and boards, both as a prosecutor and as defence counsel on behalf of professional members. Bombier regularly speaks at continuing legal education conferences and has taught trial advocacy at Osgoode Hall Law School.

Darryl A. Cruz

Law firm: McCarthy Tétrault LLP


Year called to the Bar: 1992

Darryl A. Cruz is a partner at McCarthy Tétrault LLP’s Toronto office. From 2007 to 2011, he has served as national practice group leader for litigation and was a member of the firm’s leadership team. Cruz maintains a general litigation practice, with an emphasis on commercial and professional liability issues. He has appeared as counsel at all levels of court in Ontario and in the Supreme Court of Canada. Cruz has tried jury and non-jury cases involving all areas of law, including contract law, insurance, tax, defamation, environmental, professional negligence and employment. He regularly represents physicians in medical negligence cases.

Risa M. Kirshblum

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1996

Risa M. Kirshblum is a partner at Lenczner Slaght Royce Smith Griffin LLP. She represents both plaintiffs and defendants in a broad range of litigation matters. A significant portion of her practice is focused on professional liability, medical negligence and health care law. Kirshblum acts as prosecutor, defence counsel and independent legal counsel in the administrative law context. She frequently presents in continuing legal education programs for organizations such as the Law Society of Ontario and The Advocates' Society. Kirshblum has also presented in continuing education programs for a variety of medical organizations.

Paul H. Le Vay

Law firm: Stockwoods LLP


Year called to the Bar: 1988

Paul H. Le Vay is partner at Stockwoods LLP. He devotes his practice to corporate and commercial litigation, securities litigation, regulatory and public law, professional liability and regulation, claims against directors and officers and employment litigation. He has also acted for clients in several class proceedings. Le Vay is bilingual and argues cases in English and French before all levels of courts and tribunals, including the Ontario Securities Commission. He is a member and former director of The Advocates' Society.

Matthew B. Lerner

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 2008

Matthew B. Lerner serves as a partner at Lenczner Slaght Royce Smith Griffin LLP. His litigation practice is focused on complex commercial litigation and professional liability matters. Lerner’s professional liability practice is directed at regularly defending physicians in civil and regulatory proceedings and prosecuting on behalf of several professional regulators. In his commercial litigation practice, Lerner has acted on behalf of directors and officers in the defence of large multi-jurisdiction class actions. He is routinely involved in a variety of insolvency proceedings, acting for the court-appointed officer or creditors. Lerner has appeared as lead counsel at all levels of court in Ontario, various administrative tribunals and in many private arbitrations. His clients span a wide range of industries, from large real estate developers to public companies in the information and technology sector. Lerner is also the chair of the Lenczner Slaght Moot in Legal Ethics and Professionalism, which is held annually for law students at Western Law.

William C. McDowell

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1988

William C. McDowell is a partner at Lenczner Slaght Royce Smith Griffin LLP. He appears in commercial litigation, libel and public law cases. McDowell has represented clients in many landmark cases, most notably in the Supreme Court of Canada. From 2005 to 2008, he was Canada’s Associate Deputy Minister of Justice and was responsible for civil litigation, national security and issues involving central agencies. He has acted for the chief of police in Toronto and chief adjudicator of the Independent Assessment Process of the Truth and Reconciliation Commission and served as amicus to the Superior Court in relation to Aboriginal land occupations in Brantford.

Terrence J. O’Sullivan

Law firm: Lax O’Sullivan Lisus Gottlieb LLP


Year called to the Bar: 1973

Terrence J. O’Sullivan is a partner at Lax O'Sullivan Lisus Gottlieb LLP. He devotes his practice to civil and commercial litigation, with an emphasis on business disputes, financial institution litigation, class actions, defence of regulatory charges and professional discipline matters. O’Sullivan regularly appears in all levels of courts in Ontario and other provinces, including the Supreme Court of Canada. He also acts as a mediator and an arbitrator and is a member of the Chartered Institute of Arbitrators. O’Sullivan is a co-author of the Civil Justice Review and is former chair of the Joint Committee on Court Reform of the province of Ontario. He writes and speaks extensively and is an occasional lecturer and demonstrator for the Osgoode Hall Intensive Advocacy Program.

Peter Osborne

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1992

Peter Osborne is a partner at Lenczner Slaght Royce Smith Griffin LLP. He has a broad civil litigation and administrative law practice encompassing cross-border commercial disputes, complex cross-border restructuring and insolvency cases, class actions and securities matters, professional malpractice litigation and disciplinary proceedings. Osborne advises boards of directors of public and private companies and special committees on governance, cross-border litigation and insolvency proceedings. He has also helped oversee the restructuring of some of the country’s largest companies.

Anne E. Posno

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 1993

Anne E. Posno serves as counsel at Lenczner Slaght Royce Smith Griffin LLP. She boasts extensive trial experience, with expertise in cases involving medical negligence, professional negligence and commercial disputes, especially in real estate. Posno maintains an estates litigation practice and regularly works in areas of human rights and privacy law. She has previously acted as lawyer for the Refugee Law Office. Posno appears before the Ontario Superior Court of Justice, the Toronto Commercial and Estates Lists, the Ontario Court of Appeal, the Federal Court, private arbitrations, the Human Rights Tribunal of Ontario and the College of Physicians and Surgeons of Ontario. She has also appeared before other administrative tribunals, including the Consent and Capacity Board and the Offices of the Privacy Commissioners of Ontario and Canada.

Luisa Ritacca

Law firm: Stockwoods LLP


Year called to the Bar: 2001

Luisa Ritacca has been a partner at Stockwoods LLP since 2006 and a member of the firm’s management committee since 2008. In 2018, she became the firm’s managing partner. Her practice encompasses a wide variety of areas, including administrative law and civil and commercial litigation. Ritacca received an order-in-council appointment as a part-time member of the Licence Appeal Tribunal in 2016. She also serves as counsel for the Canadian Centre for Ethics in Sports and has appeared on several anti-doping cases over the last several years. Ritacca acts for students facing academic and non-academic-related charges at secondary and post-secondary institutions throughout Ontario. She also acts as independent legal counsel for several regulated health colleges and administrative tribunals throughout the province. In this role, she provides substantive and procedural advice during hearings and ongoing training for adjudicators. Ritacca was appointed by former Chief Justice Warren Winkler to act as court monitor in the administration of two pan-Canadian settlements involving the tainted blood scandal and the settlement involving water contamination in Walkerton, Ontario.

Matthew Sammon

Law firm: Lenczner Slaght Royce Smith Griffin LLP


Year called to the Bar: 2002

Matthew Sammon is a partner at Lenczner Slaght Royce Smith Griffin LLP. He boasts extensive litigation experience across a broad range of areas, including complex corporate and commercial litigation, employment, and professional liability and medical malpractice cases. Sammon regularly conducts trials, regulatory hearings and arbitral proceedings. His clients include large and mid-sized corporations across a wide range of sectors such as financial services, banking, telecommunications, retail, health care, manufacturing, hospitality, and oil and gas. Sammon also acts regularly for executives and other individuals in civil and regulatory disputes. He has deep experience in professional regulation and medical malpractice litigation.

Caroline R. Zayid

Law firm: McCarthy Tétrault LLP


Year called to the Bar: 1990

Caroline R. Zayid is partner at McCarthy Tétrault LLP’s Toronto office and the firm’s litigation national practice group leader. She specializes in civil litigation, with an emphasis on class actions, product liability and administrative law. Zayid has successfully represented clients in the pharmaceutical industry, financial services, manufacturing and public sector in defending class action litigation. She has also acted on leading cases dealing with judicial supervision of national class actions, waiver of tort, preferable procedure, fraud on the market and evidentiary standard for certification. Zayid boasts extensive experience in the litigation of professional regulatory issues on behalf of regulators and professionals. She represents clients on judicial review applications and appeals in relation to tribunal decisions and administrative actions. Zayid has represented clients at the Supreme Court of Canada and the courts of appeal of Ontario, British Columbia and Saskatchewan. She has also represented clients  in class actions and professional regulatory matters.

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