Celebrating the Life Of

Tyrrell "Terry" Clark

April 19, 1950 - August 29, 2023

Proudly serving the Peel Region since 1978.
The Tannahill, Lockhart & Clark Law team has a combined legal experience of close to 150 years. We are proud of our history serving the legal needs of businesses and residents across Peel Region and of our reputation for personalized legal representation, caring and respect. When you work with our team, you can be confident in our ability to actively represent you and we always pursue the best course of legal action for your particular needs. You are not just another file at TLCL. We are a law firm that genuinely cares about the well-being of our clients.

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Client Testimonials

Blog Articles

Distracted Driving
Injured persons should seek advice from experienced trial lawyers regarding who is at fault for their accident. First, it was seat belts, then it was impaired driving, now, distracted driving. There are many forms of distracted driving that can arise in motor vehicle accident litigation. During the...
Compensation for Injured Airline Passengers in an International World
What happens when passengers are injured or worse, killed during the course of international air travel? With over 90,000 flights taking off every day around the world and billions of passengers flying internationally every year, aviation technology has come a long way since the Wright brothers. Unfortunately,...
What is a Litigation Guardian? Who Needs One? Should I be One?
Becoming a litigation guardian is a significant responsibility. If you are considering acting as a litigation guardian, you should consult an experienced lawyer. Who needs a Litigation Guardian? Unfortunately, serious injuries can happen to anyone, including individuals who would legally be considered...
Recreational Trails And Non-Urban Property Use: “Risks Willingly Assumed”
The Occupiers’ Liability Act informs the duty of care of owners of these types of properties. Imagine that it is a beautiful fall day, and you decide to go for a bike ride before the weather cools down. Cycling in a nearby wooded area, commonly used by your neighbourhood for outdoor activities, imagine...

Case Studies

Personal Debts : Recovery of a Cash Loan Without a Contract
Our clients, who we will call the Smiths*, were befriended by a man we will call Sam*. Sam got involved deeply in the Smiths’ lives, seeking to help them in matters of business, real estate, and spiritual matters. Sam gained the Smiths’ trust to point where they considered him a close friend and confidante. The...
Sibling Taking Advantage of Elderly Parent : Righting a Wrong
The client, who we will call Rosie*, suspected that her sister had been using a Power of Attorney to take money from her father’s account before he died. However, her sister was named as estate trustee under the Will and refused to provide any information. Rule 75.06 : Order to Compel InformationWe...
Eye Injury from BBQ
Our client, who we will call Doug, was cleaning the BBQ that he bought from a National Retailer one night. After about 20 seconds of cleaning the BBQ, some metal from the BBQ flew up into his eye. He went to the hospital that night and medical care providers removed a piece of metal from his eye. Another...
Greed and the Family Cottage
Our client, who we will call Bob* owned a family cottage property with his Aunt, with two cottages being on the same piece of land. Both Bob and his aunt enjoyed each other’s company and shared expenses of the joint piece of land over the years. The Greedy SonEventually, Bob’s aunt started to get older...

Our Team

Douglas D. Tannahill
Senior Partner
Doug Tannahill has practiced law in Brampton since being called to the bar in 1975. Doug completed his undergraduate degree at Ashland University in Ohio before taking his law degree at Osgoode Hall.  He practices in the area of Corporate and Commercial law, with an emphasis in the area of Corporate and Commercial Agreements, including Commercial Real Estate and Leasing.

John S. Lockhart
Senior Partner
John Lockhart was called to the bar in 1977, after taking his law degree at the University of Toronto, and his undergraduate degree at the University of Guelph. John started his career at the firm of West & Robb in Brampton where he met Doug Tannahill. They became partners in 1978.

Tyrrell (Terry) Clark
Senior Partner
Terry Clark has been a lawyer since 1977. He took his undergraduate degree at McMaster University and graduated from the University of Toronto Law School in 1975. After his call in 1977, Terry worked in the City Solicitor’s Office at the City of Mississauga until 1981, working solely in the area of Municipal Law and Land Development.

Timothy S. Lockhart
Tim was called to the bar in 2013 and has a broad-based civil litigation practice, including estate litigation, real estate litigation, commercial litigation, and construction lien actions. Tim’s non-litigation practice includes commercial and residential real estate, wills and estates, and charity law. Tim uses a personal touch with all his clients and is always personally available to take clients through the legal process step by step.

Olga Wagner
Office Manager
Olga Wagner has been with Tannahill Lockhart & Clark since 1988. Olga began her career with the firm as our receptionist. Her professional manner and engaging voice and smile have been long time attributes to the TLC Family. In 2007 Olga became the Office Manager, continuing to manage the telephone and reception area while carrying out the day to day maintenance of the office.

Leilani Hawkins
Senior Law Clerk, Litigation, Wills and Estates
Leilani Hawkins is a Senior Law Clerk who has been with our firm since 1991. She works in the areas of Litigation and Wills and Estates. After attending Ryerson in their Business Management Course, Leilani began her career in Toronto, and came to work with Tannahill, Lockhart & Clark when she relocated to Brampton, and then Georgetown with her husband and children.

Sonja Syme
Senior Law Clerk, Real Estate/Wills and Estates
Sonja is a Senior Law Clerk at Tannahill, Lockhart & Clark and is responsible for significant commercial and industrial sales and purchases, land development projects and the purchase and sale of large tracts of vacant land. She also processes the sale of homes in residential subdivisions for home builders whom we represent.

Eleanor Mairs
Senior Law Clerk, Real Estate/Wills/Estates
Eleanor Mairs joined Tannahill, Lockhart & Clark in 1994.  After graduating from Sheridan College, Legal Secretarial Program, Eleanor worked in the legal field prior to joining our firm.  Eleanor is the legal assistant to Douglas Tannahill and is responsible for Corporate and Commercial matters, Real Estate and Wills and Estates.


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