Ralph Hanke made a terrible mistake on Jan. 8, 1995, while resurfacing an ice rink in Edmonton, Alberta. On that day he filled the gas tank of his Zamboni-like machine with hot water. The gas tank on the machine, which was made by Resurfice Corp., is next to the water tank. The hot water caused the gas in the tank to evaporate and drift toward an overhead heater. The vapor ignited in a massive explosion, scorching 90 percent of Hanke's body.
Soon after Hanke filed a negligence claim against Resurfice. Relying on the "but for" test to determine causation, the trial court denied his claim. Under the "but for" test a plaintiff must prove the injury wouldn't have occurred but for the negligent conduct of the defendant.
That's what happened in 2004 when the Ontario Court of Appeal used the "but for" test to correct a trial court decision. In this case, Cottrelle v. Gerrard, the plaintiff was a diabetic who sued her physician. The plaintiff had gone to see her doctor after developing a sore on her foot. The physician did not examine her, but instead referred her to a skin specialist. Soon after, the sore became infected and doctors amputated her leg.
Despite evidence the amputation was inevitable, the trial court, which used the material contribution test, found in favor of the plaintiff. It deemed that because the physician didn't examine the foot, he significantly contributed to its infection. However, on appeal, the court applied the "but for" test and corrected the lower court's mistake.
But others see some remaining ambiguities in Canada's tort law that lower courts will have to sort out in the future.
"This case doesn't really clarify the law," says Gordon McKee, partner at Blake, Cassels & Graydon. "It affirms that the 'but for' test is the basic test in Canadian law and that the material contribution test is only available in exceptional circumstances, but beyond that, what material contribution means is still a matter of confusion."