Tree Liability Risk: The Duty of Care Owed to Persons Who May Be Harmed by Trees

Question: Who is liable for damages caused by falling trees in Ontario?

Answer: In Ontario, property owners and those responsible for tree maintenance must ensure trees are safe. Liability for damages occurs if it is known, or should have been known, that a tree posed a risk, but proper care was not taken (Occupier's Liability Act, R.S.O. 1990, c. O.2). Ignorance of dangerous conditions after events like storms may result in liability. For tailored legal advice and support, contact us today.

Liability Involving Tree Maintenance

The value and benefits of trees are often overlooked and the potential liability risks associated with trees are often underestimated or misunderstood. It is important for owners, contractors, and other individuals to take due care of trees so to minimize the potential for trees to cause injury or damage and thus to minimize the potential liability risks.

The Law

Duty of Care

Property owners have a duty to ensure that other people and the property property of other people are reasonably safe from harm arising from the negligence of a property owner. Such a duty in law was established within the general principles case of, among others, Donoghue v. Stevenson, which established the legal test for duty of care within the basic principles of negligence law. In Ontario, such a duty of care is also codified per the Occupier's Liability Act, R.S.O. 1990, c. O.2, wherein it is stated:

Negligently Performed Maintenance

Owners of trees, or others responsible for trees (such as hired maintenance contractors), generally face liability only when it was known, or constructively known, that a tree failure risk was present and the owner (or others) failed to properly tend to the tree.  In this way it can be thought that the injury or damage was a result of delay in caring for the tree rather than the result of risks inherent in a tree.  Essentially, the negligent failure to maintain is a man-made risk rather than a natural tree risk. On the point of liability for failure to maintain trees, such was addressed within the case of Hallok v. Toronto Hydro Electric System Ltd., 2003 CanLII 8519, wherein it was said:

As such, it seems that knowledge, or constructive knowledge, of a dangerous condition is a requirement of liability for negligent maintenance of trees.  Note that "constructive knowledge" is knowledge which the law deems a person ought to have based on reasonableness.  If a reasonably diligent person would know of a dangerous condition this is "constructive knowledge" and proving actual knowledge becomes unnecessary.  Constructive knowledge is often much easier to prove than actual knowledge.  For example, following severe storms, property owners should reasonably be on alert for broken branches as well as other dangerous conditions.  Additionally, it is important to recognize that intentionally avoiding investigation and thereby choosing to remain unaware of a dangerous condition may be deemed an act of willful blindness from which constructive knowledge may also be imposed.

Conclusion

The owners of trees, or those entrusted with the care and maintenance of trees on behalf of the owners, owe a duty of care to reasonably ensure that the trees are maintained.  If a person becomes injured or property becomes damaged by a tree that was improperly maintained, liability for the injury or damage may arise.