Assumed Future Fact Scenarios Are OK In Economic Expert Reports

Reasons for judgement were released recently by the BC Supreme Court, Victoria Registry, addressing the appropriateness of assumed future fact scenarios in an economists report.  In short the Court held that such assumptions could be laid out in the body of a report.
In the recent case (Hill v. Murray) Mr. Justice Macaulay provided the following comments on this topic:
[7] In Sacilloto v. Crossman (1990), 49 B.C.L.R. (2d) 375 (S.C.), the defence objected to an economist’s report that set out various possible scenarios for the expected earnings of the plaintiff, based on the assumption that he had not been injured in the accident, along with further scenarios for possible earnings after the accident.
[8] The court pointed out that many of the assumptions underpinning the report were at issue in the trial and, as a result, it would be impossible for counsel or the economist to rely on one assumption as to facts. The court considered the use of several scenarios to be in harmony with the fact that there were a number of live issues at trial. On admitting the report, the court stated:
(12) I am left with the impression that the author of the report has endeavoured … to tie the statistical data to the various possible scenarios that I may find or may not find applicable to the plaintiff. In doing so, he has endeavoured to mould the report to the likely evidence scenarios before the Court. That opinion evidence to me is useful evidence. It provides me with materials which, from my general experience both before and after coming to the Bench, I would not otherwise have.
(13) The case here is not a simple looking ahead for someone who has worked for many years and has established his working pattern in life. …
(14) Here, I am dealing with a young man who is embarking upon a working career, who on the evidence … was in a state of flux as to what he would do in the future … The type of evidence that has been put before me is such that I could not from my own experience pluck it out of my mind and arrive at reasonable estimates as to what might lie ahead depending on the findings of fact that I make.
Although this case suggests that admissibility may depend on the complexity of the calculations involved and the uncertainty of the future options for the plaintiff, the use of the scenarios does not in itself render the material inadmissible.
[9] Finally, the Court of Appeal implicitly improved the admission and use of such expert opinion material in Jurczak v. Mauro, 2013 BCCA 507. In that case, the economist provided an expert opinion on loss of earning capacity based on two sets of assumptions arising out of the plaintiff’s pre-accident work history and proffered scenarios in each case.
[10] Although the Court of Appeal overruled the trial judge’s approach to determining future loss of earning capacity, the court commented, “if there are mathematical aids that may be of some assistance, the court should start its analysis by considering them.” A failure to do so may result in a wholly erroneous estimate of the damages (both at paragraph 37).
[11] In this regard, I am satisfied that the sections of the reports and tables to which the defendant objects in the present case are admissible.
To my knowledge these reasons for judgement have not yet been publicly published but, as always, I am happy to share a copy with anyone who contacts me and requests them.