Not Your Fault? Navigating Ontario’s Fault Determination Regime

Ontario’s Fault Determination Rules (“the Rules”) outline over 40 common collision scenarios each depicted with simplistic diagrams. Each collision scenario has a corresponding liability percentage assigned to each driver.  These Rules are largely used by your insurance company to determine who is at-fault for an accident.

The challenge for drivers and insurance adjusters is determining which templated scenario in the Rules fairly applies to the accident. This is no easy task as accidents often result due to a unique sequence of events and may be caused by a combination of factors including distracted driving and traffic conditions. These factors, along with weather, the condition of the roadway, and lighting, are not considered when determining fault under the Rules. The insurer is tasked with selecting a diagram that most closely resembles the impact. If a diagram does not readily apply, fault will be determined by applying the “ordinary rules of negligence” which is often open for interpretation as well.

The Percentage Problem

Fault percentages are used to process direct compensation claims quickly and efficiently. However, they are often applied based on insufficient or incomplete collision information. Many times, collisions are deemed to be a split liability scenario if there are conflicting accounts on how the accident occurred. The apportionment of fault determined by the insurance adjuster may seem arbitrary and unfair to the driver who experienced the collision first-hand.

Does Making a Claim Raise my Premiums?

The answer is no. A claim itself should not increase your insurance premiums on renewal. Individuals purchase insurance so they are protected by the coverage they paid for in the event of an accident. Therefore, a policy holder is entitled to access these benefits without worrying about penalty or repercussions. That said, if an individual is found more than 25% at fault, the insurer can raise their premiums on renewal (unless eligible for accident forgiveness). Further, if a driver is determined to be “at-fault”, their property damage deductible will apply.

Remedies for Drivers Found At-Fault

Regardless of the apportionment of fault applied by your insurance company, you may still have the right to sue others for their negligence if it contributed to the cause of the accident.

If you do not agree with how the insurance company has assessed fault, the driver should inquire into which particular fault rule was applied and any other factors that were considered. Typically the insurer has an internal review process and many disputes are resolved at that stage. Ask their insurer to review their decision. If the dispute cannot be resolved internally, consider filing a complaint with the Financial Services Commission of Ontario or consulting a lawyer to seek redress through the Court.

Help Yourself

Without saying, your insurance company will be in a better position to properly assess fault if they are provided with complete and accurate information regarding the collision. Drivers would be prudent to personally exchange information with all people involved in the accident as well as any individuals who witnessed the collision. The Motor Vehicle Accident Report is not always accurate and sometimes may exclude witness information if it was not provided to the police at the scene.

It is important to remember that even if you are determined to be at-fault to some extent for an accident, or even charged with an offence, you may still have the right to sue. The Fault Determination Rules are not determinative of civil negligence. A personal injury lawyer can help you assess the liability scenario and let you know if you have any recourse.


Acknowledgments and thanks to Anindita Asaduzzaman for her assistance with the research and writing of this blog post.

Michael Giordano
Written by

Michael Giordano is a founding partner of Avanessy Giordano LLP. Prior to establishing his own practice, he was a partner of a prominent Mississauga personal injury firm.

He completed his law degree at the University of Ottawa. Prior to law school, Michael studied English and Law & Society at York University.

Michael is an active member of the Ontario Trial Lawyers Association and is the current Vice-Chair of the New Lawyers Division. He is a regular contributor to the OTLA blog and has also written for The Litigator.