Product liability claims are a complex but essential part of the personal injury landscape. After all, when a person is injured due to the negligence of a manufacturer or seller, they have the right to seek damages for their injuries and losses. 

However, advancing a product liability claim isn’t always as simple as proving that a manufacturer or seller acted negligently or breached the terms of a contract. In many cases, the wrongful actor will attempt to advance defences to shift liability for the claim back on the claimant or another party. 

Below, we’ll provide a quick refresher on product liability claims before introducing you to some of the more common defences manufacturers and sellers use against product liability claims. As every product liability case turns on unique facts, speak with an experienced personal injury lawyer for guidance. 

A Refresher on Product Liability Claims

Product liability claims arise when a consumer is injured or suffers other losses due to a defective or poorly designed product. These types of claims may be brought under contract or tort law. We will discuss product liability claims that arise in contract law (in other words, where an actual contract exists between the parties). 

You may suffer injury or loss if you purchase a product with a warranty that does not work as expected. You might bring a product liability claim based on the manufacturer’s failure to meet a condition (a “fundamental obligation” of the contract) or a warranty (a “promise or statement” about the product in the contract) in the contract. 

If a contract exists, the injured party must prove that they relied on a condition or warranty of the contract, and by relying on that condition or warranty (e.g., that the product would perform as anticipated), they suffered injury or loss. If they can prove that a condition or warranty in the contract was breached, the injured party can take action against the manufacturer. 

Defences in Product Liability Claims

Sellers or manufacturers defending a product liability claim may raise many defences depending on the type of product liability claim. Below, we’ll discuss some common product liability claim defences. 

Limitation Periods

In Ontario, the Limitations Act, 2002, SO 2002, c 24, Sch B states that most claims must be started within two years of the day the claim was discovered. Under this legislation, the date a claim is “discovered” is the earliest of (a) the date on which the injury, loss, or damage occurred or (b) the date on which a reasonable person ought to have known it occurred. 

As a result, if a product liability victim attempts to bring a claim outside of the standard limitation period, the seller or manufacturer will use a “limitation defence”, arguing that the claim should be dismissed because it was not brought within the appropriate time frame. 

Contributory Negligence

Suppose a product liability victim brings their claim in tort law. In that case, the seller or manufacturer may attempt to establish that the victim’s negligence in using or interacting with the product contributed to their loss or damage (either in whole or in part). 

In Ontario, the Negligence Act, RSO 1990, c N.1 offers a framework that helps apportion liability in negligence cases where a defendant alleges that the claimant was negligent. 

Let’s say the court finds that the claimant’s actions contributed to their injury. In that case, the court will apportion damages in proportion to the degree of fault or negligence found between the parties. When the court cannot determine the extent to which the claimant is contributorily negligent, they will likely determine that the claimant and defendant are equally at fault. 

Misuse of Products

A similar defence to contributory negligence is that the claimant suffered loss or damages because they used a product in a manner that the seller or manufacturer did not intend or reasonably expect. For example, if a product liability claimant stood on top of a dresser to change a lightbulb, and the dresser toppled and injured the claimant, the manufacturer or seller may argue that the claimant’s injuries and loss arose due to their misuse of the product. 

Learned Intermediary

Given that products often end up in the hands of a buyer through a complex manufacturing and purchasing process, defendants in product liability claims will sometimes argue that they are not liable for resulting injuries and losses due to the actions of a “learned intermediary”. For example, if an individual suffers medical issues due to a malfunctioning medical device and sues the manufacturer. In that case, the manufacturer may argue that the person who sold the medical device to the buyer (the “learned intermediary”) is responsible for the resulting issues because they failed to exercise due care in prescribing the product or making the right representations. 

Manufacturers’ Warranties and Exclusions of Liability 

Depending on whether a warranty or contract was involved in the purchase, manufacturers and sellers may be able to defend against product liability claims by relying on warranties or exclusion of liability clauses. 

A manufacturer’s warranty typically guarantees the product’s quality and provides recourse on how issues relating to the product will be handled. While these warranties can be useful for buyers who have issues with the product (for example, the warranty might state that the manufacturer will replace the product if it doesn’t work), they can also contain provisions regarding liability or recourse in the event of an issue (for example, the warranty might provide for the replacement of the product but exclude liability for other issues or losses relating to the product). 

The exclusion of liability clauses also sometimes appears in product contracts. These clauses might state, for example, that the seller or manufacturer is not responsible for any losses or damages arising from a purchaser’s use of the product. 

Both manufacturer’s warranties and exclusion of liability clauses have received differing treatment from the courts, so whether a manufacturer will successfully argue these defences depends on the nature of the case and the terms of the warranty or exclusion of liability. 

Final Thoughts on Defenses in Product Liability Claims

As a personal injury claimant, it’s important to understand the potential defences that a manufacturer or seller might raise in a product liability claim. Thankfully, a skilled personal injury lawyer will be able to analyze your case and assess the likelihood of these defences being raised long before trial, helping you understand how your case will likely be perceived by the court and prepare to present your case in the best light possible. 

Ottawa Personal Injury Lawyers Assisting Product Liability Claims

You may be entitled to compensation if you are injured by a defective product or a manufacturer’s negligence. Tierney Stauffer LLP’s product liability team will help you get the compensation you need to recover from your injuries and move forward with expert advice at every step. To learn more about how our experienced product liability lawyers can help you achieve compensation for your product liability case, call us at 1-888-799-8057 or contact us online to speak with a member of our team.


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