Source: https://davidcheifetz.ca/2012/12/18/a-problem-with-boilerplate/
Timestamp: 2019-04-25 00:56:15+00:00

Document:
Those of you in British Columbia who (need or ought to) care about such things may have noticed an almost boilerplate quality in the paragraphs in recent British Columbia Supreme Court decisions setting out the principles of factual causation in negligence. This, on the whole, is a good thing and the judges should be commended.
On the other hand, what’s not good is that the boilerplate is literally wrong. (It’s still safe for me to say these things since I don’t have to appear in front of British Columbia judges.) So far, though, that hasn’t seemed to affect the validity of the judges’ decisions.
A very recent example is Erickson v. Sibble, 2012 BCSC 1880. This is the boilerplate.
For Ms. Erickson to recover damages, there must be a causal link between the Accident and the injuries she has suffered. The law does not draw a distinction between injuries that are psychological or physical in nature. The primary test used in determining causation is known as the “but for” test. The plaintiff bears the burden of showing that “but for” the defendant’s negligent act or omission, her injury would not have occurred. Applying it here requires that Ms. Erickson prove that it is more likely than not likely that without the Accident her injuries would not have occurred: Athey v. Leonati,  3 S.C.R.; 458; Blackwater v. Plint,  2 S.C.R. 3.
 The causation test does not demand scientific precision and is not to be applied too rigidly: Snell v. Farrell,  2 S.C.R. 311. Causation is a practical question of fact which can best be answered by ordinary common sense.
 The plaintiff need not establish that a defendant’s wrongful conduct is the sole cause of her injury. So long as the plaintiff establishes a substantial connection between the injuries and the defendant’s negligence beyond the “de minimis” range, the defendant will be fully liable for the harm suffered by a plaintiff, even if other causal factors, which he is not responsible for, were at play in producing the harm: Farrant v. Laktin, 2011 BCCA 336; Athey; Resurfice Corp. v. Hanke, 2007 SCC 7; Clements v. Clements, 2012 SCC 32.
 … The essential purpose and most basic principle of tort law is that the plaintiff must be placed in the position he or she would have been in absent the defendant’s negligence (the “original position”). However, the plaintiff is not to be placed in a position better than his or her original one. It is therefore necessary not only to determine the plaintiff’s position after the tort but also to assess what the “original position” would have been. It is the difference between these positions, the “original position” and the“injured position”, which is the plaintiff’s loss. In the cases referred to above, the intervening event was unrelated to the tort and therefore affected the plaintiff’s “original position”. The net loss was therefore not as great as it might have otherwise seemed, so damages were reduced to reflect this.
Erickson is a thin skull (pre-existing injury) case.
 This court confirmed in Moore v. Castlegar& District Hospital 1998 CanLII 4906 (BC CA), (1998), 49 B.C.L.R. (3d) 100 (C.A.) that “where both parties have led expert evidence on the issues of causation, it is not open to this court to apply the ‘common sense’ reasoning urged in Snell” (para. 11).
Both sides called expert evidence in Erickson. However para. 221 is the only time the trial judge mentioned Snell or common sense, so perhaps the trial judge didn’t apply “common sense” reasoning, whatever that means, assuming that means something different from otherwise valid reasoning, in deciding whether to accept the plaintiff’s evidence (including expert evidence) rather than the defendants.
For what it’s worth, the Ediger/Moore limitation on the use of the Snell common sense approach to but-for is supposed to be one of the issues in the Ediger appeal in the SCC– argued at the Supreme Court on December 4, 2012, decision reserved. My recollection is that the point was mentioned in passing in argument. There was certainly no suggestion from either side that the Snell approach could not be applied because expert evidence had been called.
It merits repeating that factual causation is always established by “inference”. All conclusions of fact in law are inferences drawn from facts. Some day, some unfortunate litigant is going to have to spend money in a fight about what the SCC meant by “where ‘but-for’ causation is established by inference only”.
There are a number of problems with para. 222 as written. I’ll mention two.
In any event, para. 222 doesn’t seem to be about remoteness or damages assessment.
The second problem I’ll mention is that para. 222 was probably meant to refer to instances where the various causal factors, even those for which the defendant “is not responsible” are cumulatively necessary to make up the cause of the injury. Limited in that fashion, the paragraph is a correct statement of the law. However, what does “other causal factors, which [the defendant] is not responsible for, were at play in producing the harm” literally mean. As written, it covers even those instances where the “other causal factors” are capable of being but-for causes even if the defendant’s negligence had not occurred, whether the other causal factors are all tortious or all “innocent”.
If there was a never actionable (i.e., innocent) causal event – other than the injured person’s own contributory fault – which would have been a but-for cause of the injury even if the negligence had not occurred, then the damages are not actionable. This problem is connected to the problem in para. 220. I’ve set out the paras. from Athey, above.
That paragraph has to be understood as meaning the situation where the evidence is enough to show that each of the different acts referred to would be a but-for cause even if all of the other negligent acts had not occurred. Otherwise, it becomes a statement of the scenario to which the material contribution to risk test summarized in para. 46(2) Clements applies, but the premise of that situation is that the evidence is NOT enough to allow the court to validly identify any one of the multiple negligent causes is a but-for cause, or to say that any two or more or all of them cumulatively combine, where the premise also is that those causal candidates are the only relevant candidates.

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