“Thin-Skull” vs “Crumbling-Skull” Rule: How Could a Pre-Existing Injury Affect My Claim?

posted in: Personal Injury

If you have recently been involved in a motor vehicle accident or slip-and-fall accident in Alberta, and have suffered physical or psychological injuries, you may be wondering whether your pre-existing injuries will affect the amount of compensation you will receive. Courts in Alberta like to use two different rules when analyzing pre-existing injuries: the “Thin-Skull” rule and the “Crumbling-Skull” rule. Understanding the differences between these two rules is crucial for assessing how a pre-existing injury will affect a claim in personal injury law.

What is the “Thin-Skull” Rule?

One of the first rules of personal injury law is the victim must be returned to a position that he or she would have been in had the accident not occurred. Simply put, the thin-skull rule is that pre-existing conditions that make a person more prone to injury do not absolve the defendant from being fully liable for all the damages caused or contributed to by the defendant’s actions (Athey v Leonati, 1996 SCC). The person responsible for causing the injuries shall take their victim as they find them and be liable for the full extent of their damages, even if the victim’s injuries are more severe than they would be for another person.

Imagine that you are involved in a motor vehicle accident in which the other driver is at fault. You have a pre-existing back condition that makes you prone to injury. The accident worsens your back condition, and your resulting injuries are far worse than someone with a healthy back would have suffered. Under the “Thin-Skull” rule, the defendant is liable for the full extent of your injuries, even though the pre-existing injury or condition made the outcome worse.

Full Compensation Under the “Thin-Skull” Rule

The “Thin-Skull” rule is crucial for ensuring that victims receive fair compensation for their injuries. It prevents defendants from arguing that they should not be fully responsible for the plaintiff’s injuries since the plaintiff was more vulnerable by reason of a pre-existing condition. This principle upholds the idea that justice should be based on the actual harm caused, not on the average or expected outcome. If your pre-existing injury or condition is made worse, you are entitled to full compensation for your worsened injuries. The defendant cannot use your condition as an excuse to reduce their liability.

What is the “Crumbling-Skull” Rule?

The “Crumbling-Skull” rule acknowledges that certain pre-existing injuries or conditions would have naturally deteriorated over time, irrespective of the accident. This rule limits the defendant’s liability by recognizing that the victim’s condition was likely to worsen regardless of the defendant’s actions.

Imagine your back condition was degenerative and would have worsened over time, even without the accident. Under the “Crumbling-Skull” rule, your compensation will be reduced to reflect the portion of the injury that would have occurred naturally due to the progression of the pre-existing injury or condition.

Adjusted Compensation Under the “Crumbling-Skull” Rule

While the “Thin-Skull” rule holds defendants fully liable for the plaintiff’s injuries, the “Crumbling-Skull” rule accounts for the plaintiff’s pre-existing condition that would have deteriorated over time, regardless of the accident. If your condition would have deteriorated over time, your compensation might be adjusted to account for the natural progression of your condition. The defendant, in this case, is only liable for the portion of the injury directly caused by their actions. In other words, the defendant will be liable for the amount his or her actions “sped up” the natural progression of your pre-existing condition.

Proving Your Injuries Were Caused by The Defendant’s Actions

Where a victim has a pre-existing condition, it becomes necessary for the court to consider the situation from a hypothetical world in which the accident did not occur (Jenkins v 0702117 B.C. Ltd., 2021 BCSC). In completing this assessment, a court will be able to determine whether the injuries would have occurred with or without the accident in question. The courts in Canada will apply the “but for” test to establish liability. Essentially, if a Court can confidently say, “but for the defendant’s actions, the victim would not have suffered these injuries,” there will be sufficient standing to hold the defendant liable for the victim’s injuries.

How Can An Injury Lawyer Help Prove That My Condition Was Worsened by the Defendant’s Actions?

To increase the likelihood of full compensation via the “Thin–Skull” rule, a victim should provide clear evidence of how the accident impacted their pre-existing condition. An injury lawyer can help you in providing clear evidence to help show that your condition has worsened as a result of your accident utilizing the following aspects of your case:

• Medical Records: Medical records documenting your pre-existing condition and any treatments received both before and after the accident. This could include doctor’s notes, tests, results, and treatment plans. Doctors and other medical-care providers keep these documents on record. If you are not aware of such records, don’t worry: our injury lawyers know how to request and obtain such records.

• Medical Experts: Experts can provide testimony on how the accident exacerbated the victim’s condition, and the likely progression of the pre-existing condition had the accident not occurred. This testimony can help distinguish between the impacts of the accident and the natural progression of the victim’s pre-existing condition.
• Accident Evidence: Injury lawyers will gather evidence related to the accident, such as photos, witness statements, and police reports. These documents may help establish the defendant’s liability for the accident.

Understanding the “Thin–Skull” and “Crumbling-Skull” rules is essential if you have a pre-existing injury and are involved in an accident. These doctrines ensure that you receive fair compensation, reflecting the true impact of the defendant’s actions on your condition.

KMSC Law Can Help Navigate Complex Injury Claims

The thin skull vs. crumbling skull rule is just one example of the complex legal issues that can arise in personal injury cases. If you have pre-existing injuries or conditions, don’t let them deter you from seeking the compensation you deserve.

The experienced Injury Law Team at KMSC Law has a deep understanding of these intricate legal principles. We’re dedicated to fighting for the rights of injured Albertans, regardless of their medical history. We’ll thoroughly assess your unique situation, build a strong case on your behalf, and advocate for the full compensation you’re entitled to.

Don’t let pre-existing conditions undermine your claim. Contact KMSC Law today for a free consultation and learn how we can help you navigate the complexities of your case.