Tessa-Marie Grossi is an associate lawyer practicing in all areas of family law, including separation, divorce, parenting, child and spousal support, property division, and the negotiation of cohabitation, marriage and separation agreements. 

Tessa-Marie graduated from Queen’s University Belfast, School of Law in 2020. While in law school, Tessa-Marie’s achievements include placing first in the Queen’s University Belfast Mediation Competition and representing her university at the ICC International Commercial Mediation Competition in Paris, France, in 2019. Her leadership skills were recognized when she was elected the QUB Alternative Dispute Resolution Society President for the 2019-2020 school year. Tessa-Marie has always taken an immense interest in alternative dispute resolution as she appreciates what a useful tool it can be to de-escalate tense circumstances.

Following the completion of law school, Tessa-Marie furthered her legal education by obtaining a Master’s of Law from Osgoode Hall Law School in 2021. Prior to law school, she excelled academically, earning an Honours Bachelor of Arts with a specialization in Criminal Justice and Public Policy from the University of Guelph in 2017.

In her spare time, Tessa-Marie enjoys exploring new recipes, spin classes, travelling, and immersing herself in new book pages. Her diverse interests and experiences contribute to her well-rounded approach to law, making her a valuable asset to her clients.

Nicolas is an associate in the civil litigation department. He has a broad civil litigation practice with a particular focus on employment law. Nicolas was called to the bar in 2023 after completing his articles with Barriston. He advises parties regarding their legal rights and remedies and guides them through the dispute resolution and litigation process. Nicolas has successfully represented clients through dispute resolution and at various administrative tribunals and levels of court, including the Landlord and Tenant Board, Human Rights Tribunal of Ontario, Small Claims Court, and Ontario Superior Court of Justice. Nicolas is certified to conduct workplace investigations into complaints and misconduct, and sits on the board of the Simcoe County Law Association.

Nicolas obtained his honours Bachelor of Arts with high distinction from the University of Toronto where he majored in Criminology and Sociolegal Studies. He went on to study law at Queen’s University Faculty of Law and graduated in 2022. While in law school, Nicolas was a member of the Queen’s Law Litigation Society and he volunteered with Pro Bono Students Canada. Nicolas developed strong analytical and research skills as a research assistant, reviewing jurisprudence regarding evidentiary matters in sentencing racialized criminal offenders. Before joining Barriston, Nicolas spent a summer working with the Queen’s Business Law Clinic where he provided pro bono legal services to individuals and businesses that wouldn’t otherwise be able to afford legal advice.

In his spare time, Nicolas enjoys exercising his competitive side through sports like crossfit, soccer, golf, and volleyball, as well as unwinding with family and friends.

Sarah Hahn’s practice is focused on municipal litigation, including municipal law, land-use planning, development, administrative and expropriation law.

She regularly appears before the Ontario Land Tribunal (OLT) and all levels of court in Ontario, acting for municipalities, private landowners and developers.

Some of the specific issues that Sarah deals with include: appeals and motions at the OLT; expropriation matters; official plan and zoning by-law amendments; minor variance and consent applications; site plan approvals and agreements; expropriation representation; development charge disputes; conflict of interest and municipal election matters; drafting municipal bylaws and resolutions; freedom of information and privacy matters; court applications for property matters such as title rectification, vesting orders, prescriptive easements and rights of way.

Sarah earned her law degree at the University of Ottawa and was called to the Ontario Bar in 2013. She sat on the Municipal Section Executive of the Ontario Bar Association for a number of years and was its Chair for the 2023 – 2024 term. She regularly presents at continuing professional development programs for lawyers and previously taught the LAWS2000 course at Georgian College. Before attending law school, Sarah worked at a Community Legal Clinic where she represented individuals at appeals before the Social Benefits Tribunal.

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NOTABLE DECISIONS:

David Harris-Lowe advises clients in all areas of family law and estate litigation, in particular relating to property and support disputes. He has represented clients at all levels of court in Ontario and has worked as a Dispute Resolution Officer in the Superior Court of Justice. He is also an accredited mediator and provides mediation services through Resolv’d Inc.

Before his call to the bar David graduated from the Royal Military College of Canada (1993) and from Queen’s University (1996) where he obtained his law degree. He is a member of the Ontario Bar Association, the Simcoe County Law Association and the Simcoe County Family Law Association. David is also a member of the community liaison committee for the Simcoe/Muskoka Supervised Access Centre.

Outside of work David is active in sports, back country camping and spending time with his family.

Barrie Hayes graduated from the University of Windsor law school in 1979. Since graduation Barrie has been providing legal services and representation in the Simcoe County area. Barrie practices mainly in the areas of family law and estates litigation. Barrie is a certified mediator and was a dispute resolution officer for the Superior Court Of Justice Family Court Branch.

Barrie is a member of the Simcoe County Family Law Lawyers Association, the Simcoe County Criminal Law Lawyers Association and the Ontario Bar Association. Barrie is a past president for the Simcoe County Law Association, the Simcoe County Family Law Association and was a member of the executive committee for the Ontario Bar Association – Family Section. Barrie holds the Osgoode Certificate in Elder Law.

Barrie is a past board member for the Barrie and District Chamber of Commerce, Stevenson Memorial Hospital, Stevenson Memorial Hospital Association, Mary McGill Mental Health Center, Community Living Association for south Simcoe and not-for-profit housing associations.

Gillian Hayes is a Partner practicing in the Family Law department.

Gillian assists clients in all areas of family law, including parenting issues, child support, spousal support, division of property, and the negotiation domestic contracts. Gillian is a Member of the Personal Legal Rights Panel for the Office of the Children’s Lawyer. Gillian represents parents and other caregivers in child protection matters. Gillian is trained in Collaborative Family Law and applies the settlement-focused elements of Collaborative Family Law to all of her files.

Gillian earned an LL.B. (Honours) from the Faculty of Law at the University of Kent in the United Kingdom and completed a Bachelor of Arts degree at Western University where she majored in Political Science.

While pursuing her law degree, Gillian was an active member of the Kent Law Clinic and participated in forming the Canadian Law Society at the University of Kent. Gillian was also integral in creating the Canadian Law Moot competition at Kent and has attended the University to speak to students on returning to practice law in Canada.

In her spare time Gillian enjoys spending time with her husband and daughter, playing ice hockey, shopping and travelling.

Gillian was called to the Bar of the Law Society of Ontario (LSO) in 2012.

Pamela is an associate lawyer practicing in the areas of corporate/commercial law, and intellectual property law, with a focus on trademarks. Pamela was called to the Bar in June 2023 after completing her Articling term with Barriston.

Pamela completed her Juris Doctor degree from Bond University in Australia in 2021. Pamela received a Bachelor of Arts (Honours) degree in Law and Society from York University.

Prior to Law School, Pamela obtained her Law Clerk diploma and worked in corporate and securities law. Here, Pamela’s passion for business law grew exponentially and influenced her decision to attend Law School.

While pursuing her law degree, Pamela interned at a start-up company on the Gold Coast where she worked with in-house counsel on corporate governance, risk management and international patent and trademark applications. Pamela also participated in the Pro Justitia Moot Competition 2019, and obtained her Independent Insolvency Practitioners Certification 2020 (Aus), and her Chartered Tax Advisor Accreditation 2021 (Aus).

In her spare time, Pamela enjoys hiking and taking her German Shepherd, Mica (a rescue from Australia) to the beach. Pamela also enjoys spending time with family and friends.

Vanessa Locicero is an associate lawyer practicing exclusively in estate litigation.

She had the privilege of sharpening her advocacy skills at boutique litigation firms as a young lawyer, and then operated her own firm in Collingwood while practicing as a solicitor, prior to joining Barriston LLP in 2026.

Vanessa has experience across a broad array of practice areas, including commercial litigation, catastrophic personal injury, corporate/commercial, contracts, and estate & trust planning.  Her litigation background and cross-disciplinary issue-spotting allow her to identify where risk, ambiguity, and conflicts are likely to arise, while her solicitor experience helps support clients to make proactive, thoughtful decisions and implement those strategies before issues escalate.

Vanessa obtained an Honours Bachelor of Arts from Queen’s University in 2011 with a double major in political science and religious studies, and later attended culinary school, where she earned her Culinary Business Management Honours Diploma from Humber College. She then attended the University of Windsor Faculty of Law, where she graduated in 2017.

Throughout law school, Vanessa completed the Canadian Securities Course, volunteered in theatrical productions to raise money for women’s charities, and also competed in moot court competitions. In the Davies Corporate/Commercial Moot Court, she placed second individually among participants from across Canada. She was called to the Bar of the Law Society of Ontario in June 2018.

In 2020, Vanessa completed the Osgoode Certificate in Negotiation, and in 2021, completed the Osgoode Intensive Program in Wills & Estates. In 2025, after seeing up close the toll that an estate dispute can take on families and inspired by her conversations with clients about the challenges of dealing with estate conflicts, she obtained the Osgoode Professional Development Certificate in Estate Litigation.

Vanessa is a Mentor with the South Georgian Bay Business Enterprise Centre, providing support to new entrepreneurs, and also sits as the Secretary on both the Board of Directors for Community Futures South Georgian Bay and the Board of Directors for Home Horizon, a youth transitional housing shelter which helps youth at risk of or experiencing homelessness.

When Vanessa is not hard at work, she enjoys reading, cooking and hosting for family and friends, exploring spirituality, and getting into nature with her husband Matt and their two chocolate labradors.

Graham offers sound and timely advice on corporate acquisitions and dispositions, corporate financial services, with an emphasis on secured financing and mortgage lending, and incorporations, shareholder and partnership agreements, mergers, leasing and franchising. His real estate practice addresses both private and corporate conveyancing and financing.

Graham has practiced trade mark and copyright law since 1983. He has completed his course requirements for a Masters of Law degree in Intellectual Property and has published in the Intellectual Property Journal. Graham has taken mediation training at CDR Associates in Boulder Colorado.

Graham is a founding member of the Barrie Arts Council, and founding member of Three Links Co-operative Housing in Barrie bringing 80 units of affordable housing to Barrie, the Founding Board President of the MacLaren Art Centre, founding Board Member of Gilda’s Club Simcoe/Muskoka and a founding Associate Member of the Canadian Association of Family Enterprise Georgian Bay Chapter. He is a past president of the Barrie Canoe Club and a member of the Canadian Bar Association and the Simcoe County Law Association.

In 2015 Graham was awarded the MacLaren Legacy Award in honour of his sustained leadership and commitment to making Barrie a wonderful community. Graham enjoys hiking with his wife Stephanie in remote regions, spending time at his cabin in Algonquin Park and composing and playing music.

After too many years fighting for clients in a slow, expensive and user-unfriendly court system, Doug decided there was a better way to solve their family law problems. So, since 1998 a significant part of Doug’s practice has been providing representation for clients in mediation and arbitration processes and acting as a mediator or arbitrator for spouses who both wish to resolve their family issues this way instead of through litigation. This better way now takes up about 15% of Doug’s practice.

Also, in 1998 Doug received the recognition of the Law Society of Ontario (LSO) as a “Specialist in Family Law” and he has maintained this status to the present. Doug was the first lawyer in Simcoe County to receive this recognition. Doug is also one of very few lawyers in the province who has a wealth of knowledge in the topics of Adoption Law and the Representing of Children in Custody and Access Disputes. He co-authored a legal text on Adoption Law in Canada several years ago.

Since graduating from Law School at the University of Windsor in 1982 and being called to the Bar of the Law Society of Upper Canada in 1984, Doug has provided sound legal advice in all areas of family law including child support, spousal support, property division, corporate/business issues that impact on separation or divorce, child protection, child custody/parenting plans, etc.

Doug has been a guest speaker at the University of Windsor Faculty of Law, at the Ontario Provincial Police Academy and has contributed articles to local newspapers and legal publications throughout his career. Doug has also contributed to the legal and local communities through his work for, and memberships in, the Rotary Club of Barrie, Rainbows Canada, Simcoe County Family Law Lawyers Association, Ontario Bar Association and the Office of the Children’s Lawyer.

Doug retired from practice in October 2019 and now acts as a consultant in our Family Law department.