In ICBC Injury Claims that proceed to trial there are often 2 competing medical theories with respect to the cause and extent of injury. Typically Plaintiff’s rely on the opinions of their treating physicans and sometimes the opinions of Indepmendent Medical Examiners. ICBC, on behalf of the Defendant, usually rely on the opinions of an independent physician who examines the Plaintiff pursuant to Rule 30 of the BC Supreme Court Rules.
When the conflicting expert evidence is presented at trial the lawyers can cross examine the opposing expert(s) opinion. This process can be a powerful tool in helping the judge or jury decide whose opinion should be preferred and given more weight. What happens if the expert is not cross-examined? Does that experts opinion carry more weight with the court? Reasons for judgement were released today by the BC Supreme Court (Yip v. Chin) dealing with this issue.
In today’s case the Plaintiff sued for injuries cuased in a 2006 Car Crash which took place in Vancouver, BC. The Plaintiff suffered from a pre-existing degenerative condition and suffered soft tissue injuries in the crash. One of the key issues at trial was whether the Car Crash had any effect on the Plaintiff’s pre-existing degenerative arthritis.
The Plaintiff’s physicain feld that this pre-existing condition was aggravated by the car crash. The doctor hired by the Defendant, Dr. Schweigel, disagreed. Dr. Schweigel’s report was intorduced into evidence unchallenged by the Plaintiff. Ulimately the Court preferred Dr. Schweigel’s opinion on this narrow issue. Mr. Justice Voith summarized and applied the law as follows with respect to the failure to cross-examine an expert witness at trial:
 The evidence of both Dr. Lui and Dr. Schweigel was consistent in concluding that at the time of the Accident Mr. Yip suffered from some degenerative arthritis of the cervical spine. The two experts differed, however, on the significance of this pre-existing condition and on whether the Accident caused this condition to be aggravated.
 The plaintiff chose not to cross-examine Dr. Schweigel. This decision places different parts of Dr. Schweigel’s reports in different categories and requires different treatment by the court. Some portions of Dr. Schweigel’s reports stand uncontradicted in that no part of the evidence led by the plaintiff takes issue with the opinions expressed by Dr. Schweigel. Other portions of his reports are inconsistent, for example, with the report of Dr. Lui or with the evidence of Dr. Lui and Dr. Leung.
 For lay witnesses, the case of Browne v. Dunn (1893), 6 R. 67 (H.L.) provides well understood guidance on the consequences that flow from the failure of a party to cross-examine on a given issue or to put given propositions to a witness. The rule arising from that case is one which is designed to ensure that witnesses and the parties are treated fairly.
 Failure to cross-examine an expert on a contested issue gives rise to additional concerns or difficulty. The very object of proffering expert evidence is to assist the trier of fact with the necessary scientific basis upon which to assess evidence. Inherent in the fact that evidence has been tendered by an expert, is the proposition that the trier of fact is generally neither conversant nor familiar with the subject matter of the evidence and lacks the independent means by which to weigh or measure the merits of two competing views.
 In this instance, for example, Dr. Lui expressed the view that Mr. Yip’s ongoing degenerative problems of the spine were likely aggravated by the Accident. This conclusion is apparently based on differences that exist in an initial x-ray taken in July 2006 which showed degenerative changes at C6-7 only and a subsequent CT scan performed on October 2007 which showed degenerative changes involving C3-4, C4-5, and C5-6 as well.
 Dr. Schweigel’s report, conversely, expresses the view that these changes are attributable to the additional sophistication of the CT scan. In Dr. Schweigel’s view, a CT scan will routinely pick up abnormalities which are missed by an x-ray. Dr. Lui, in his cross-examination, firmly disagreed with this conclusion. The court did not have benefit of any further explanation from Dr. Schweigel. The trier of fact is thus left with two competing views, one of which, though contradicted, remains unchallenged by cross-examination.
 No inflexible rule can be established as to the significance of a party failing to cross-examine an expert. Sometimes a party will be aware that the expert will not resile from his position and cross-examination would be futile. Thus, in Palmer v. Goodall (1991), 53 B.C.L.R. (2d) 44 (C.A.) at 49, the Court said in relation to a notional cross-examination, “It may be a mere show. The law of evidence does not require counsel to engage in a charade”.
 In this instance, I believe it is appropriate to attach some weight or significance to the fact that Dr. Schweigel’s report was introduced without any part of its contents being tested further. This is not a case of a party failing to cross-examine on a particular portion of the report. This is an instance of the plaintiff deciding to leave untested all of the various opinions which are offered in relation to a number of issues, notwithstanding the fact that such opinions are often at odds with the evidence tendered by the plaintiff.