Black Holes, Aether, and Negligence in the Air: Causation in Negligence in Canada after Clements

Abstract

The article examines the changes in the law in Canada's common law jurisdictions governing proof of factual causation in negligence after the Supreme Court of Canada's decisions in Clements v. Clements, 2012 SCC 32 and Resurfice Corp. v. Hanke 2007 SCC 7. The article examines the requirements of the new material contribution to risk test which is based on the possibility, but not the probability, of factual causation and the traditional but-for test which is said to be based on probability and necessity and not merely probability and sufficiency. The material contribution to risk doctrine was formally introduced into Canadian common law jurisprudence in 2007 by Resurfice Corp. v. Hanke. Clements restates and explains aspects of material contribution to risk doctrine and attempts to provide a bright-line test for those instances where the material contribution doctrine may be applicable assuming that, for qualifying reasons, the but-for test cannot be validly used to prove or disprove factual causation on the balance of probability. Clements also emphasizes the primacy of the but-for test and what is described as the common sense, robust, and pragmatic approach to the application of the but-for test. The focus of the article is primarily on what the law now is and the issues that creates, not what the law ought to be. However, there is some prescription; for example, the likely still quixotic suggestion that a sufficiency-based test for factual causation (such as the NESS test) is a better solution than the but-for test. Revised as of December 24, 2012