BA (Western Ontario), LLB (Osgoode), of the Bar of Ontario, is a partner in the Toronto office of Heenan Blaikie LLP. Mr. MacKenzie's practice is focused on professional liability and discipline litigation, class actions and general civil and commercial litigation. He has appeared as counsel before courts at all levels including the Supreme Court of Canada, as well as before many tribunals, including the Competition Tribunal, the Ontario Securities Commission, and the professional conduct and discipline committees of numerous professional and regulatory agencies.

Mr. MacKenzie has been honoured by induction as a Fellow of the American College of Trial Lawyers. He has been an elected bencher of the Law Society of Upper Canada since 1995. He has chaired the Law Society's Professional Regulation Committee, which is responsible for professional conduct and discipline, its Strategic Planning Committee and its task force on the reform of the Rules of Professional Conduct. Then, in 2006, he was elected Treasurer, the highest position in the Society.

Mr. MacKenzie has often been retained as an expert witness on professional responsibility in litigation in the United States and in Canada and is a frequent speaker at continuing education programs.

Mr. MacKenzie writes The Profession column for the Law Times and has served as a director of the Canadian Institute for the Administration of Justice and as Chair of LibraryCo Inc., the library system of Ontario Law Associations. He is among the lawyers repeatedly recommended by his peers in the annual Lexpert survey and is recognized as one of Canada's leading lawyers in the areas of Alternative Dispute Resolution and Legal Malpractice Law in the 2008 edition of The Best Lawyers in Canada (Woodward/White). Mr. MacKenzie has been awarded Martindale-Hubbell's highest rating ("AV") for his skills and sense of ethics.