This is an excerpt (with modifications) from the conclusion (Part 11) of “Black Holes, Aether“.
Whatever the Supreme Court might have intended by its restatement and explanation of the material contribution doctrine in Clements v. Clements, 2012 SCC 32, the Clements and Resurfice Corp v. Hanke 2007 SCC 7 reasons barely begin the process of clarifying the jurisprudence. If the Resurfice reasons moved the jurisprudence even one small step forward out of the shallower portions of the mire, they concurrently pushed it at least two larger strides back into deeper quagmire. The Clements reasons, because of what the Court said about both the but-for test and the material contribution doctrine, are, at best, one small step back towards the shore. Part of my conclusion in Cheifetz, “Snell Inference” [“The Snell Inference And Material Contribution: Defining The Indefinable And Hunting The Causative Snark – A Not Excessively Subtle and Theoretical Examination of Proof of Factual Causation in Canadian Tort Law” (2005) 30 Adv. Q. 1] about the state of Canadian jurisprudence on the meaning of factual causation in tort, then, was that “clarity, predictability and ease of use are not defining characteristics”. One can now predict that the but-for test will be used in most actions in tort based on negligence; otherwise, the conclusion remains correct. Resort to the smokescreen of common sense will not increase clarity or predictability.
Once upon a time, but not so long ago, the House of Lords rejected what one of the judges described as an argument calling for the “wholesale adoption of possible rather than probable causation as the criterion of liability.”  The material contribution to risk doctrine, properly interpreted, properly applied, will not be a wholesale adoption of a doctrine that permits the imposition of liability where it ought not to have been imposed. It is, nonetheless, a radical change in the common law  which was made without adequate regard to, or even acknowledgment of, the Supreme Court’s own guidelines for when such changes should be made by the Court (or, generally, courts) rather than the legislature.
At the moment, the problem is the proper interpretation of the material contribution doctrine. There are few useful judicial guidelines. The Supreme Court, in Resurfice, did not have to open up the Pandora’s Box which is the material contribution to risk doctrine. The facts of Resurfice did not require any mention of a material contribution to risk doctrine. Having chosen to, the Court now must deal with the consequences of that decision. Soon after Resurfice, the dean of Canadian tort law scholarship wrote that Resurfice “did not reflect the [Court’s] best thinking on the issue [of causation] which needs fuller treatment in the future.” That statement is equally true for Clements.
One reason for the inadequacy of the Clements and Resurfice reasons may be the Supreme Court’s apparent unwillingness to acknowledge, formally, first in Resurfice and then in Clements, that there has been anything written about the material contribution to risk doctrine in the Canadian context, to the extent we might conclude from that and the reasons that the Court did not consider that scholarship adequately. We should assume the members of the Supreme Court are well aware that the scholarship exists. This is not a complaint that the Supreme Court has not referred to anything that I have written. It is a complaint, based on the problems in the Resurfice and Clements reasons, that the Court seems to have ignored everything that anyone had written about Resurfice or Clements.
 Admitted in Clements v. Clements, 2012 SCC 32 at para. 16, even if one claims that it is not “proof of causation” that is being eliminated but, rather, what is occurring is merely the reduction of the standard of proof, in some cases, to a standard of possibility rather than probability. The probability standard is centuries old.
[3 ] The Honourable Mr. Justice Allen M. Linden, “The Triumphs and Trials of Tort Canadian Tort Law” (Calgary: Canadian Bar Association, August 14, 2007) at 21 [words in brackets added]. Online:<http://www.mjswm.com/JPM/Torts2/files/The_Triumphs_and_Trials_of_Canadian_Tort_Law.pdf> .
 Some of it commended the Supreme Court’s analysis in Resurfice. The only Canadian scholarship referred to in Clements is Weinrib, Private Law, (Cambridge, Mass.: Harvard University Press, 1995). Clements purports to adopt that text’s explanation of the relationship between tort law and corrective justice a part of the justification for the material contribution to risk doctrine: see Clements, supra note 2 at para. 7. It is not, however, the explanation of corrective justice that appears in Private Law. The result is that only scholarship the court mentioned about any version of the material contribution to risk doctrine are 2002 and 2003 English articles which discuss Fairchild; however these are mentioned in Clements only because the Supreme Court quoted a passage from a 2009 British Columbia Court of Appeal decision in which these articles were cited. See Clements, ibid. at para. 14.
 The factums filed in each of the Resurfice, Fullowka and Clements leave to appeal applications and appeals are replete with references to the scholarship.
 (1993) 27 U.B.C. Law Rev. 1.
  1 S.C.R. 541, 1991 CanLII 87.
 Supra note 2 at para. 16.
 Some of it is written by scholars who are now dead, if that matters, in Canadian publications; for example, John Fleming’s seminal articles on possibilistic causation in the Canadian Bar Review. See John G. Fleming, “Probabilistic Causation In Tort Law” (1989), 68 Can. B. Rev. 661 and “Probabilistic Causation In Tort Law: A Postscript” (1991), 70 Can. B. Rev. 136. As may be gleaned from their publication dates, the articles bracket Snell.
 The concept of causation that is part of Weinrib’s version of corrective justice is not based on the possibility that the wrongdoer’s negligence could have been a cause of the injury. It is based on the probability that it was a cause.
 Oliver Wendell Holmes,Jr., The Common Law, Lecture 1 (Boston: Little, Brown & Co.: 1881) at 1