Athey v. Leonati (1996), 203 N.R. 36 (SCC)

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[La version française vient à la suite de la version anglaise]


Jon Athey (appellant) v. Ferdinando Leonati and Kevin Johnson (respondents)

Jon Athey (appellant) v. Edward Alan Gagne, Dolphin Delivery (1985) Ltd. and Dolphin Transport Ltd. (respondents)


Indexed As: Athey v. Leonati et al.

Supreme Court of Canada

Lamer, C.J.C., La Forest, Sopinka,

Cory, McLachlin, Iacobucci and

Major, JJ.

October 31, 1996.


The plaintiff suffered back injuries in successive motor vehicle accidents in February and April 1991. During the re­covery period, the plaintiff suffered a her­niated disc while doing recommended exer­cises. The plaintiff brought a negligence action for damages against both defendant drivers. The defendants admitted liability. The only issue was whether the herniated disc was caused by the accidents or by a preexisting condition.

The British Columbia Supreme Court held that both the accidents and a preexisting condition contributed to the injury, with the accidents being assigned a 25% causative factor. Accordingly, the trial judge limited the damage award to 25% of assessed dam­ages. The plaintiff appealed, claiming that since the accidents were a cause of the injury, he was entitled to 100% of assessed damages.

The British Columbia Court of Appeal dismissed the appeal. The court held that it was inappropriate to address that theory of liability, where it had not been put to the trial judge. The plaintiff appealed.

The Supreme Court of Canada allowed the appeal and awarded judgment to the plaintiff for the full amount of assessed damages. Once the plaintiff established that the de­fendants’ negligence was a cause of the disc herniation (i.e., materially contributed to the injury outside the di minimis range), the defendants were liable for 100% of dam­ages. The loss was not to be apportioned between tortious and non-tortious causes where both were necessary to create the injury.

Damages – Topic 206

Entitlement – Chance – Loss of – Proof of reasonable probability of success – [See
Torts – Topic 59

Damages – Topic 591

Limits of compensatory damages – Pre­disposition to damage (thin skull rule) – “Thin skull” or “crumbling skull” – The Supreme Court of Canada stated that “the ‘crumbling skull’ doctrine is an awkward label for a fairly simple idea. It is named after the well-known ‘thin skull’ rule, which makes the tortfeasor liable for the plaintiff’s injuries even if the injuries are unexpectedly severe owing to a preexist­ing condition. The tortfeasor must take his or her victim as the tortfeasor finds the vic­tim, and is therefore liable even though the plaintiff’s losses are more dramatic than they would be for the average person. The so-called ‘crumbling skull’ rule simp­ly recognizes that the preexisting con­dition was inherent in the plaintiff’s ‘origi­nal position’. The defendant need not put the plaintiff in a position
than his or her original position. The defendant is liable for the injuries caused, even if they are extreme, but need not compensate the plaintiff for any debilitating effects of the preexisting condition which the plaintiff would have experienced anyway. The defendant is liable for the additional dam­age but not for the preexisting damage … Likewise, if there is a measurable risk that the preexisting condition would have detrimentally affected the plaintiff in the future, regardless of the defendant’s negli­gence, then this can be taken into account in reducing the overall award.” – See paragraphs 34 to 36.

Practice – Topic 9012

Appeals – Restrictions on argument on appeal – Issues or points not previously raised – A court of appeal refused to deal with an appellant’s argument dealing with a point of law not raised before the trial judge – The Supreme Court of Canada stated that “the general rule is that an appellant may not raise a point of law that was not pleaded, or argued in the trial court, unless all the relevant evidence is in the record … In this case, all relevant evidence was part of the record. In fact, all the requisite findings of fact had been made. The point raised by the appellant was purely a question of law. … Given that the appellant’s arguments raised an issue of law which did not require any further evidence (or indeed any further findings of fact) and which would not have caused any prejudice to the respon­dents, it was an error for the Court of Appeal to refuse to consider the argu­ment.” – See paragraphs 51 to 52.

Torts – Topic 54

Negligence – Causation – “But for” test – The Supreme Court of Canada stated that “the general, but not conclusive, test for causation is the ‘but for’ test, which requires the plaintiff to show that the injury would not have occurred but for the negligence of the defendant … The ‘but for’ test is unworkable in some circum­stances, so the courts have recognized that causation is established where the de­fendant’s negligence ‘materially con­tributed’ to the occurrence of the injury” – See paragraphs 14 to 15.

Torts – Topic 58

Negligence – Causation – Independent causes – The plaintiff’s injury was caused by the combination of two successive motor vehicle accidents and a preexisting condition – The trial judge assessed a 25% causative factor to the accidents (for which the defendants admitted liability) and limited judgment to 25% of assessed dam­ages – The Supreme Court of Canada held that causation was established where the defendants’ negligence “materially con­tributed” to the injury, which required a contribution outside the di minimis range – The defendants’ negligence need not be the “sole” cause of injury to make the de­fendants liable for the full loss – Once causation was established, the plaintiff’s loss was not to be apportioned between tortious and non-tortious causes – The court stated that if there was a measurable risk that the plaintiff’s preexisting condi­tion would have detrimentally affected him in the future, regardless of the defendants’ negligence, then the damage award would be reduced (i.e., “crumbling skull”) – Here, there was no basis to reduce the award, as there was no finding that the injury would have occurred without the accident – See paragraphs 12 to 36.

Torts – Topic 59

Negligence – Causation – Loss of chance – The plaintiff’s herniated disc injury was caused by the combination of two suc­cessive motor vehicle accidents (de­fendants admitted negligence) and a pre­existing condition – The Supreme Court of Canada stated that “the [de­fendants] sub­mitted that the accidents merely increased the risk of herniation, and that [they were] liable only for that increase in risk. This is an application of the ‘loss of chance’ doc­trine which is the subject of considerable controversy … The doctrine suggests that plaintiffs may be compensated where their only loss is the loss of a chance at a favourable oppor­tunity or of a chance of avoiding a detri­mental one. In this case, the loss would arguably be the loss of a chance of avoid­ing the disc herniation. However, this contention is not supported by the factual findings. The trial judge made no findings suggesting that the injury was a loss of chance of avoiding a disc herniation. The finding at trial was that the accidents con­tributed to the actual disc herniation itself. It is therefore un­necessary to consider the loss of chance doctrine, and these reasons neither approve nor disap­prove of the doctrine.” – See paragraphs 37 to 38.

Torts – Topic 64

Negligence – Causation – Apportionment – [See
Torts – Topic 58

Cases Noticed:

Snell v. Farrell, [1990] 2 S.C.R. 311; 110 N.R. 200; 107 N.B.R.(2d) 94; 267 A.P.R. 94, refd to. [para. 13].

McGhee v. National Coal Board, [1972] 3 All E.R. 1008 (H.L.), refd to. [para. 13].

Horsley v. MacLaren, [1972] S.C.R. 441, refd to. [para. 14].

Myers and Myers v. Peel County Board of Education and Jowett, [1982] 2 S.C.R. 21; 37 N.R. 227, refd to. [para. 15].

Bonnington Castings v. Wardlaw, [1956] 1 All E.R. 615 (H.L.), refd to. [para. 15].

R. v. Pinske (1988), 30 B.C.L.R.(2d) 114 (C.A.), affd. [1989] 2 S.C.R. 979; 100 N.R. 399, refd to. [para. 15].

Alphacell v. Woodward, [1972] 2 All E.R. 474 (D.C.), refd to. [para. 16].

School District of Assiniboine South No. 3 v. Hoffer and Greater Winnipeg Gas Co., [1971] 4 W.W.R. 746; 1 N.R. 34 (Man. C.A.), affd. [1973] 6 W.W.R. 765; 1 N.R. 32 (S.C.C.), refd to. [para. 19].

Mallett v. McMonagle, [1970] A.C. 166 (H.L.), refd to. [para. 27].

Malec v. Hutton (J.C.) Proprietary Ltd. (1990), 169 C.L.R. 638 (Aust. H.C.), refd to. [para. 27].

Janiak v. Ippolito, [1985] 1 S.C.R. 146; 57 N.R. 241; 9 O.A.C. 1, refd to. [para. 27].

Schrump v. Koot (1977), 18 O.R.(2d) 337 (C.A.), refd to. [para. 27].

Graham et al. v. Rourke (1990), 40 O.A.C. 301; 74 D.L.R.(4th) 1 (C.A.), refd to. [para. 27].

Jobling v. Associated Dairies, [1981] 2 All E.R. 752 (H.L.), refd to. [para. 31].

Penner v. Mitchell (1978), 10 A.R. 55; 89 D.L.R.(3d) 343 (C.A.), refd to. [para. 31].

Lamb v. Kincaid (1907), 38 S.C.R. 516, refd to. [para. 52].

Authors and Works Noticed:

Cooper-Stephenson, Ken, Personal Injury Damages in Canada (2nd Ed. 1996), pp. 67 to 81 [para. 28]; 748 [para. 19]; 779, 780, 851, 852 [para. 35].

Fleming, John G., Probabilistic Causation in Tort Law (1989), 68 Can. Bar Rev. 661, generally [para. 37].

Fleming, John G., The Law of Torts (8th Ed. 1992), pp. 193 [para. 17]; 201, 202 [para. 24].

King, Joseph H., Causation, Valuation, and Chance in Personal Injury Torts Involving Preexisting Conditions and Future Consequences (1981), 90 Yale L.J. 1353, generally [para. 37].

Munkman, John, Damages for Personal Injuries and Death (9th Ed. 1993), pp. 39, 40 [para. 35].

Sopinka, John and Gelowitz, Mark A., The Conduct of an Appeal (1993), p. 51 [para. 51].


Thomas R. Berger, Q.C., and Frits Verhoeven, for the appellant;

Patrick G. Foy and Vincent R. Orchard, for the respondents.

Solicitors of Record:

Edwards, Kenny & Bray, Vancouver, British Columbia, for the appellant;

Ladner, Downs, Vancouver, British Columbia, for the respondents.

This appeal was heard on June 12, 1996, before Lamer, C.J.C., La Forest, Sopinka, Cory, McLachlin, Iacobucci and Major, JJ., of the Supreme Court of Canada.

On October 31, 1996, Major, J., delivered the following judgment for the Supreme Court of Canada in both official languages.


Athey v. Leonati et al.

[1996] 3 SCR 458

Supreme Court of Canada
Reading Time:
20 minutes
Cory, Iacobucci, Major, McLachlin 

Major, J.
: The appellant suffered back injuries in two successive motor vehicle accidents, and soon after experienced a disc herniation during a mild stretching exercise. The herniation was caused by a combination of the injuries sustained in the two motor vehicle accidents and a preexisting disposition. The issue in this appeal is whether the loss should be apportioned between tortious and non-tortious causes where both were necessary to create the injury.

I. Facts

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