Court File and Parties
CITATION: Lawson v. Sullivan, 2008 ONCA 700
DATE: 2008-10-14
DOCKET: C47499
COURT OF APPEAL FOR ONTARIO
Doherty, Cronk and MacFarland JJ.A.
BETWEEN:
Ken Lawson, Christian Lawson, Megan Lawson and Katie Lawson, by her Litigation Guardian, Ken Lawson
Plaintiffs
And
Timothy Sullivan
Defendant (Respondent)
And
Hydro Ottawa Limited
Third Party (Appellant)
Counsel:
Christopher I. R. Morrison and Teri Mychasin for the appellant
Debbie Orth and L. Inglis for the respondent
Heard and released orally: September 30, 2008
On appeal from the judgment of Justice David L. McWilliam of the Superior Court of Justice dated July 3, 2007.
Endorsement
[1] We accept the trial judge’s crucial findings of fact. The trial judge was satisfied that the driver, the defendant Sullivan, was negligent when he ran into the back of the plaintiff Lawson’s vehicle. The plaintiff Lawson’s vehicle was stopped on the road as directed by the employees of the third party Hydro. Those employees were working on hydro lines immediately above and beside the road. The trial judge was also satisfied that Hydro was negligent in failing to adequately warn oncoming traffic of the need to stop for the hydro workers.
[2] The trial judge did not advert expressly to the question of causation as it related to Hydro’s negligence. The parties have agreed before us, correctly in our view, that the “but for” test must be applied in determining whether it can be said that Hydro’s negligent act caused the subsequent accident. The trial judge said this at page 15 of the reasons:
I am satisfied that had Mr. Sullivan’s inattentiveness been jarred by flashing lights ahead, his chances of being able to stop in time would have increased by at least one in four given the speed at which he was driving which was not fast, and that is why I have assessed Hydro’s contributory negligence at 25 percent in all of the circumstances.
[3] In our view, a finding that “but for” the negligence of a party there would have been a one in four chance of avoiding the accident is not a finding of causation under the “but for” analysis. The point is made by the decision of this court in Cottrelle v. Gerrard, 2003 CanLII 50091 (ON CA), [2003] O.J. No. 4194. Sharpe J.A. for the court said at para. 25:
In other words, if, on a balance of probabilities, the plaintiff fails to prove that the unfavourable outcome would have been avoided with prompt diagnosis and treatment, then the plaintiff’s claim must fail. It is not sufficient to prove that adequate diagnosis and treatment would have afforded a chance of avoiding the unfavourable outcome unless that chance surpasses the threshold of “more likely than not.” [Emphasis added.]
[4] In our view, the trial judge’s finding of fact quoted above (para. 2) amounts to a finding that there would have been a chance of avoiding the accident had Hydro not been negligent. As indicated in Cottrelle, a mere chance of avoiding the accident does not render Hydro’s conduct a “but for” cause of the accident. The further question of the apportionment of fault under the statute arises only where two or more parties have been found liable for the same injury. Without causation there can be no liability.
[5] The judgment below is set aside and an order is substituted dismissing the action against the third party Hydro.
[6] Hydro should have its costs at trial. Counsel agree that those costs should be on a partial indemnity basis and are confident that they can agree upon the amount of those costs. Insofar as the appeal is concerned, Hydro is entitled to its costs on a partial indemnity basis. We fix those costs at $15,000.00, inclusive of disbursements and GST.
“Doherty J.A.”
“E. A. Cronk J.A.”
“J. MacFarland J.A.”

