If a dog attacks someone, then its owner may be responsible for any damage caused by the dog. However, the way in which you may be liable will depend on the circumstances. Under the Dog Owner’s Liability Act, you are liable for any damages caused by the dog if you are the dog’s “owner” as defined under the Act. However, even if you are not the dog’s “owner”, you may still be liable under the Occupier’s Liability Act for failing to ensure that your premises were reasonably safe for people coming onto your property. You may also still be liable at common law for negligence.
Liability of Dog’s “Owner” under the Dog Owner’s Liability Act?
Section 2(1) of the Dog Owner’s Liability Act says that a dog’s owner is liable for all damages caused by the dog:
2(1) Liability of owner: The owner of a dog is liable for damages resulting from a bite or attack by the dog on another person or domestic animal.
The Act states that a dog owner is liable for all damages caused by the dog regardless of whether the owner knew or did not know about the dog’s propensity to attacks others, or whether the owner was negligent. Under sections 2(3) and (4) the Act, the owner is liable for any damages caused by the dog, and the only defence available to the owner would be to argue that the plaintiff was partly to blame for his own negligence or contribution to the attack:
2(3) Extent of liability: The liability of the owner does not depend upon knowledge of the propensity of the dog or fault or negligence on the part of the owner, but the court shall reduce the damages awarded in proportion to the degree, if any, to which the fault or negligence of the plaintiff caused or contributed to the damages.
2(4) Contribution by person at fault: An owner who is liable to pay damages under this section is entitled to recover contribution and indemnity from any other person in proportion to the degree to which the other person's fault or negligence caused or contributed to the damages.
The Court of Appeal adopted this interpretation of the Act in Wilk v Arbour.
The Act, however, only says that an “owner” is liable. Section 1(1) clarifies the definition of a dog’s “owner”, and states that an “owner” includes someone who “possesses” or “harbours” a dog. The question, however, is whether the definition of “owner” is restricted to the actual owner, or whether it should also include people who merely had possession of the dog at the time of the attack, such as dog-sitters.
The Ontario Court of Appeal in Wilk v Arbour explored the definition of a dog “owner” under the Act. The parties in this case had been in a romantic relationship when the plaintiff offered to take the dog out for a walk. The dog suddenly suffered a seizure and fell into a ditch. The plaintiff jumped into the ditch to help the dog, but it suddenly awoke and bit off her thumb. She sued the defendant for the damages caused by the dog, and argued that the defendant was the dog’s “owner”, and was therefore liable for all damages caused by it. Conversely, the defendant argued that the plaintiff was in possession of the dog at the time of the bite, and he was therefore the dog’s “owner” for the purposes of the Dog Owner’s Liability Act. According to this line of reasoning, the plaintiff would be barred from recovering damages from the attack, since the Act only allows for non-owners to seek damages against owners. In other words, the plaintiff defined an “owner” as the person that actually owned the dog, while the defendant defined an “owner” more broadly to include someone that had immediate possession over the dog.
The motions judge in Wilk v Arbour ruled that the “owner” of a dog was only the actual owner, and did not include the person who merely had immediate possession of the dog at the time of the attack. Therefore, the plaintiff was not an “owner”, and she was therefore entitled to recover for the harm caused by the dog.
However, the Ontario Court of Appeal disagreed with the lower courts. Weiler JA pointed out that the definition of an “owner” in the legislation includes someone who “possesses” or “harbours” a dog. She argued that this language indicates the legislators’ intension to have a broad definition of ownership. Weiler JA summarized her position in paras 30, 33, and 36:
“30…In defining "owner" to include a person who "possesses" or "harbours" a dog, the legislature indicated an intention to impose liability on persons who had less than the full collection of rights belonging to an owner but who had attributes of ownership, possession and harbouring (providing safe shelter to the dog) where a measure of control over the dog is exercised…
33…The legislature wished to make those who were in a position to exercise a measure of control over a dog responsible for its behaviour. This makes sense as the person exercising actual control over a dog is generally in the best position to avoid damage being caused by the dog to another person or animal.
36…I would hold that the word "possesses" in the definition of "owner" under the DOLA includes a person who is in physical possession and control over a dog just before it bites or attacks another person or animal…”
In short, the Ontario Court of Appeal overruled the motions judge, and declared that an “owner” of a dog could include someone that had immediate possession of the dog at the time of the attack but was not the dog’s true owner. Thus, the plaintiff, as the person in immediate possession of the dog at the time of the attack, was its “owner” and her claim was barred. The law, therefore, casts a wide net of liability beyond merely the full owner of a dog. Even a person who is merely in possession of a dog at the time of the attack is liable for all damage caused, with little ability to raise any defence.
Dog Attacks under the Occupier's Liability Act
Even if someone is not a dog’s “owner” as defined under the Dog Owner's Liability Act, a person may still be liable under the Occupier's Liability Act. However, the overlap between these two acts of legislation is somewhat complicated.
The Occupier’s Liability Act at section 3(1) establishes that the occupier of a property is responsible for ensuring that the premise is reasonably safe for anyone entering onto it:
3(1) Occupier's duty: An occupier of premises owes a duty to take such care as in all the circumstances of the case is reasonable to see that persons entering on the premises, and the property brought on the premises by those persons are reasonably safe while on the premises.
The question, however, is whether a plaintiff may sue a dog owner for a dog attack because the occupier did not keep his premise reasonably safe under the Occupiers’ Liability Act, or whether he can only sue under the Dog Owner’s Liability Act. Section 3(1) of the Dog Owner's Liability Act resolves this issue by establishing that liability under the Occupier’s Liability Act does not apply if the person is an “owner” under the former act of legislation:
3(1) Application of Occupier's Liability Act: Where damage is caused by being bitten or attacked by a dog on the premises of the owner, the liability of the owner is determined under this Act and not under the Occupier's Liability Act.
The court in Hudyma v Martin cited this passage when it ruled that the Dog Owner’s Liability Act superseded the Occupier’s Liability Act in cases where an occupier was also a dog’s “owner” as defined by the former Act.
More recently, however, the court in Elbaum v York Condominium Corp No 67 held that the Occupier's Liability Act may apply in cases where someone did not meet the definition of a dog “owner” under the Dog Owner’s Liability Act:
“As I interpret the civil liability provisions of the Dog Owner's Liability Act, if the defendant is the owner or harbourer of the dog and the plaintiff's damage was caused by being bitten or attacked by a dog on the premises of the owner, the liability of the owner is determined under the Dog Owner's Liability Act and not under the Occupier's Liability Act.
However, as I interpret the civil liability provisions of the Dog Owner's Liability Act, if the court determines that the defendant is not the owner or harbourer of the dog, then there is no strict liability, but there is also no preclusion of a common law negligence claim or a claim under the Occupier's Liability Act.”
Belleghen J reached a similar conclusion in Graham (Litigation Guardian of) v 640847 Ontario Ltd. Therefore, although the Occupier’s Liability Act does not apply if a person is an “owner” under the Dog Owner’s Liability Act, it may still apply if someone is not an “owner” under that Act.
A Dog’s Owner’s Liability in Negligence at Common Law
The courts have not yet established that an “owner” under the Dog Owner’s Liability Act cannot also be liable in negligence under common law. In fact, In Wilk v Arbour, the plaintiff sued the defendant under both the Dog Owner’s Liability Act and for liability under common law negligence. Weiler JA of the Ontario Court of Appeal ruled that the basic elements of negligence apply to cases of animal attacks: “1) whether the defendant owed the plaintiff a duty of care; 2) whether the defendant's behaviour breached the standard of care; 3) whether the plaintiff sustained damage; and 4) whether the defendant's breach caused the plaintiff's harm in fact and law.”
However, the court also ruled that “special circumstances” are required in order for the owner of any domestic animal to be liable in negligence:
“…To establish liability for animals in negligence, special circumstances must exist. The owner of an animal cannot be negligent if the animal acts in an unexpected way and injures someone. For a person to be held negligent there must be foreseeability of harm and unreasonable conduct, or put another way, it must be found that "the owner of the particular animal, with its particular characteristics, in the particular circumstances have reasonably foreseen the danger that could result in damage."”
Unlike under the Dog Owner’s Liability Act a dog owner is not liable for common law negligence simply because the dog attacked another person. Any harm caused by the dog would need to have been reasonably foreseeable having regards to the dog’s particular pattern of behaviour. An owner would only be liable if his dog acts in a way that is reasonably foreseeable, and not unexpected or unusual.
Nevertheless, the Court of Appeal demonstrated that the liability of a dog owner for common law negligence is fact-specific and depends on the standard elements of negligence. It ultimately held, not that the dog owner was negligent, but that the defendant’s alleged negligence was not a sufficiently proximal cause of the injury. The plaintiff’s decision to jump into the ditch after the dog was an intervening act that rendered her injury too remotely separated from the alleged negligence of the plaintiff. In other words, the issue was decided on whether remoteness broke the chain of causation under the particular facts of the case. The rigid and wide-spanning liability under the Dog Owner’s Liability Act does not apply.
The Courts have decided that a dog’s “owner” under the Dog Owner’s Liability Act is not restricted to the true owner, but also includes the person who had immediate possession of the dog at the time of the attack. Nevertheless, even if someone is not the dog’s “owner” under this broad definition, that person could still be liable under the Occupier's Liability Act if that person should have reasonably foreseen that the dog would cause harm to visitors. An owner may also be liable for negligence at common law. Dog owners must therefore be aware of their legal responsibilities so as to avoid complications that may arise if their dog attacks others.
 Dog Owners' Liability Act, R.S.O. 1990, c. D.16, s 2(1) .
 Ibid at ss 2(3) and (4).
 Wilk v Arbour, 2017 ONCA 21 at para 31, 407 DLR (4th) 222 .
 DOLA, supra note 1, s 1(1).
 Wilk, supra, note 3 at paras 3-11.
 Ibid at paras 12-13.
 Ibid at para 28.
 Ibid at paras 30, 33, 36.
 Ibid at paras 37.
 Occupier’s Liability Act, RSO 1990, c O2, s 3(1)
 DOLA, supra note 1, s 1(1), supra note 1, s 3(1).
 Hudyma v Martin (1991), 27 ACWS (3d) 1088 at paras 10-13 (Ont Ct J (Gen Div)).
 Elbaum v York Condominium Corp No 67, 2014 ONSC 1182 at paras 19-20.
 Graham (Litigation Guardian of) v 640847 Ontario Ltd (2005), 141 ACWS (3d) 879 (Ont Sup Ct J).
 Wilks, supra note 3 at para 40.
 Ibid at paras 42-43.