Minister of Justice and Attorney General of Canada announces judicial appointments in the province of Ontario

October 14, 2025 – Ottawa, Ontario – Department of Justice Canada  

The Honourable Sean Fraser, Minister of Justice and Attorney General of Canada and Minister responsible for the Atlantic Canada Opportunities Agency, today announced the following appointments under the judicial application process established in 2016. This process emphasizes transparency, merit, and the diversity of the Canadian population, and will continue to ensure the appointment of jurists who meet the highest standards of excellence and integrity.

The Honourable Christine Mainville, a Judge of the Ontario Court of Justice in Toronto, is appointed a Judge of the Superior Court of Justice of Ontario in Toronto. Justice Mainville replaces Justice K.G. Hood (Toronto), who elected to become a supernumerary judge effective April 30, 2025.

Carolyn R. Leach, Deputy Legal Director, Property Rights, at the Ministry of the Attorney General – Office of the Children's Lawyer in Toronto, is appointed a Judge of the Superior Court of Justice of Ontario in Toronto. Justice Leach replaces Justice F. Kristjanson (Toronto), who resigned effective June 20, 2025.

Sharon A. Tysick, Crown Attorney at the Ministry of the Attorney General – Criminal Law Division in North Bay, is appointed a Judge of the Superior Court of Justice of Ontario in North Bay. Justice Tysick replaces Justice G. Ellies (North Bay), who elected to become a supernumerary judge effective September 30, 2025.

Rosemarie A. Juginovic, Executive Legal Officer at the Office of the Chief Justice of the Superior Court of Justice of Ontario in Toronto, is appointed a Judge of the Superior Court of Justice of Ontario in Brampton. Justice Juginovic replaces Justice M. Rahman (Brampton), who was elevated to the Court of Appeal for Ontario on March 7, 2025.

J. Scott Cowan, Principal at Cowan Law Chambers in Thornbury, is appointed a Judge of the Superior Court of Justice of Ontario in Owen Sound. Justice Cowan replaces Justice M.G. Emery (Brampton), who elected to become a supernumerary judge effective September 16, 2025. Due to internal transfers by the Chief Justice, the vacancy is located in Owen Sound.

Edward M. Iacobucci, Professor at the Faculty of Law of the University of Toronto, is appointed a Judge of the Superior Court of Justice of Ontario in Toronto. Justice Iacobucci replaces Justice K.B. Corrick (Toronto), who elected to become a supernumerary judge effective August 6, 2025.

Quote

“I wish Justices Mainville, Leach, Tysick, Juginovic, Cowan, and Iacobucci every success as they take on their new roles. I am confident they will serve Ontarians well as members of the Superior Court of Justice of Ontario”.

— The Hon. Sean Fraser, Minister of Justice and Attorney General of Canada and Minister responsible for the Atlantic Canada Opportunities Agency

Biographies

Justice Christine Mainville was born and raised in Ottawa. After studying criminology at the University of Ottawa, she graduated from McGill Law and obtained a Masters in comparative criminal law from the Université Paris 1 Panthéon-Sorbonne. She then clerked for the Honourable Ian Binnie at the Supreme Court of Canada. She was called to the Quebec Bar in 2007 and the Ontario Bar in 2011.

Justice Mainville was appointed to the Ontario Court of Justice in 2023. After practicing criminal law in Montreal, she moved to Toronto where she practiced criminal, penal and disciplinary law with Henein Hutchison Robitaille LLP for 13 years, where she became partner. There, she conducted trials and appeals in both English and French and appeared before all level of courts including the Supreme Court of Canada. She was also co-lead counsel in the Ottawa LRT Public Inquiry, and senior counsel at the Independent Street Checks Review.

Justice Mainville has presented at many conferences on the topic of criminal law. She has also been a mentor with McGill University’s Women in Leadership Mentorship Program and volunteered for the Cornell Center on the Death Penalty Worldwide. She was a founding member and later an advisory board member of Innocence McGill, a legal clinic investigating wrongful conviction claims.

Justice Carolyn R. Leach holds an LL.M. (2015, Civil Litigation & Dispute Resolution) and an LL.B. (1995), both from Osgoode Hall Law School, and a B.A.H. from Queen’s University (1992). She was called to the Ontario Bar in 1997.

Justice Leach spent the first 20 years of her career at the Office of the Children’s Lawyer, representing children at all levels of court in family law and child protection matters. In 2018, she was seconded to the Ministry of Children, Community and Social Services where she provided legal advice to the government on child welfare policy, litigation, and legislative reform. In 2022, she moved to the Indigenous Justice Division, a branch of the Attorney-General dedicated to addressing justice issues that affect Indigenous peoples. As part of this role, she acted as Coroner’s Counsel in inquests into the deaths of Indigenous persons. In January 2025, she returned to the Office of the Children’s Lawyer as Deputy Legal Director, Property Rights. Here, she led the delivery of legal services for minors in estate/trust, personal injury and other civil proceedings.

Justice Leach had served on the Board of the Association of Family and Conciliation Courts (Ontario chapter) since 2017, including terms as Co-President and as Chair of the Walsh Family Law Moot & Negotiation Competition. She was a frequent presenter on topics related to child representation. 

Justice Leach and her husband Chris have three adult children. She enjoys cooking, reading and spending time with family, friends and her lively Australian cattle dog.

Justice Sharon A. Tysick was raised in Northern Ontario in a small community near the Quebec border. She attended Queen’s University in a Bachelor of Commerce program before attending law school. She obtained a Bachelor of Law at Queen’s University in 1996. She was a law clerk to the Right Honourable Beverley McLachlin at the Supreme Court of Canada in 1997. She was called to the Ontario Bar in 1998. 

Justice Tysick began her legal career at Kemp, Maille, Regimbal, Hamel & Tysick where she had a general practice and conducted prosecutions for the Public Prosecution Service of Canada. In 2003, she began working for the Ministry of the Attorney General as an Assistant Crown Attorney. She prosecuted many serious cases in the Ontario Court of Justice and Superior Court of Justice including homicide, sexual violence, intimate partner violence and child abuse trials. In 2013, she became the Acting Crown Attorney for the District of Temiskaming and continued in that capacity until she became the Crown Attorney for the District of Nipissing in 2021. 

Justice Tysick has served her community as previous Treasurer for Small Pond Entertainers (children’s theatre), director on the boards of Victim Services of Temiskaming and The Capitol Centre, North Bay, and has performed as vocalist/actor in community fundraising events. 

Justice Tysick most enjoys spending time with her husband Mark and her 4 adult children.

Justice Rosemarie A. Juginovic graduated with a Bachelor of Arts (B.A.) from the University of Victoria, British Columbia and graduated from Dalhousie University law school in 2000.  She was admitted to the Bar of Ontario in 2002.

Justice Juginovic started her legal career in the Scarborough Crown Attorney’s Office where, for nearly 20 years, she prosecuted criminal cases at both the Ontario Court of Justice and the Ontario Superior Court of Justice including the most serious and complex criminal cases. Prior to leaving the Scarborough Crown Attorney’s Office, she was one of its Deputy Crown Attorneys from 2017 to 2021. She continued her legal career with the Office of the Chief Justice of the Superior Court of Justice of Ontario, serving as Senior Criminal Counsel from 2021 to 2023, before being appointed Executive Legal Officer in May 2023.

Justice Juginovic was an instructor in various continuing legal education and trial advocacy programs throughout her career. She is a strong advocate of continuing education and co-founded an educational initiative called “WELL” – Women Educating in Law & Life - a forum for female members of the criminal bar to share practice tips, teach and engage in substantive law issues, gain insight into how to improve and expand advocacy skills, and to build collegiality and mentoring relationships.

Justice J. Scott Cowan was born and raised in Markham. He received his B.A. from Carleton University in 1997 and LL.B. from the University of Saskatchewan in 2000. He obtained his LL.M from Osgoode Hall Law School in 2012. He was called to the Ontario Bar in 2002.

Justice Cowan articled with Greenspan, Henein, and White before working with now-Justices Derstine and Penman as an associate lawyer. Since starting his own practice, he has conducted hundreds of criminal trials and appeals across Ontario. In 2009, he began practicing in Canada’s North, conducting numerous matters across 25 Inuit and First Nations communities in Nunavut and Northwest Territories.  

Justice Cowan has served as a Director of the Criminal Lawyers’ Association and President of the Huron Law Association. He has taught as an adjunct professor at Western University and presented at numerous continuing legal education events and conferences. He has served as volunteer counsel with the Legal Aid Exceptions Committee, Innocence Canada’s Review Committee, and the Pro Bono Inmate Appeal Program. In the community, he spent 14 years as President of his property owner’s association, as an executive in a local service club, and has volunteered with numerous sports and leisure clubs.

Justice Cowan is married to his brilliant partner, Nicolle, and is proud father to four amazing children and one energetic dog.

Justice Edward M. Iacobucci was born and raised in Toronto. He received an LL.B. from the University of Toronto (gold medalist), an M.Phil. from the University of Oxford (Rhodes Scholar), and a B.A (Hons) from Queen’s University (highest standing in the Faculty of Arts). He clerked for Justice John Sopinka at the Supreme Court of Canada. He was called to the Ontario Bar in 2003.

Justice Iacobucci has been a professor at the Henry N.R. Jackman Faculty of Law, University of Toronto for over twenty-five years, teaching and writing on a variety of business, regulatory, and commercial law subjects, and is a past winner of the Mewett Award for Excellence in teaching. He served as Dean for six years starting in 2015, where his priorities included increasing student financial aid and expanding student learning opportunities. He has been invited to be a visiting professor at a number of law schools, including NYU, Columbia, the University of Chicago, Tsinghua University and the National University of Singapore. 

Justice Iacobucci has engaged with the legal and broader community in a variety of ways. He has consulted on law and policy for various private and public bodies. He has also served on Governing Council of the University of Toronto and various other boards, including those of the Investment Industry Regulatory Organization of Canada (now Canadian Investment Regulatory Organization), the John and Myrna Daniels Foundation, and the Empire Life Insurance Company.