The Supreme Court Takes Another Stab At The Application Of The 'Material Contribution' Test: Clements v. Clements And The Law Of Proof Of Causation In Negligence

Introduction

When seeking to recover damages in connection with harm resulting from another's negligence, an injured party must establish on a balance of probabilities that the tortfeasor caused the injury in question. The requirement that an injured party establish a causal connection between the negligent act and the resulting harm has been recognized to anchor the law of negligence to one of its underlying purposes, that of corrective justice.

The long standing test applied by the Canadian Courts to the proof of causation is the "but for" test. Applied in both single cause as well as multi-cause injuries, the test requires the plaintiff to demonstrate that "but for" the defendant's negligent act, the injury would not have occurred. However, the Supreme Court of Canada has ruled in the past that in certain exceptional circumstances, a Court may apply the "material contribution" test in place of the "but for" test. The "material contribution" test allows an injured party to avoid the need to prove "but for" causation and only requires proof that the negligent action materially contributed to the risk of harm.

In the case of Clements v. Clements 2012 SCC 32 ("Clements"), the Supreme Court on the one hand narrowed the application of the "material contribution" test, but in obiter comments, suggested that the test's application may be expanded in the future.

The Clements Case

Mr. and Mrs. Clements were involved in a motorcycle accident, with Mr. Clements operating the motorcycle, and Mrs. Clements riding behind him as a passenger. The bike was approximately 100 pounds overloaded and unknown to Mr. Clements, a nail had punctured the bike's rear tire. As Mr. Clements accelerated to pass a car, the nail fell out causing the rear tire to deflate. Unable to bring the bike under control, Mr. Clements crashed the bike and as a result, Mrs. Clements, the passenger, suffered a traumatic brain injury. Mrs. Clements then sued Mr. Clements claiming her injury was caused by his negligent operation of the bike.

The Trial Judge found Mr. Clements' negligence had contributed to Mrs. Clements' injury. In finding liability, he used a "material contribution to risk" test for causation as opposed to the usual "but for" test. He felt that on an evidentiary basis, Mrs. Clements could not establish that her injuries would not have occurred "but for" Mr. Clements' negligence in overloading the motorcycle and driving too quickly. As it was only, "through no fault...