Skip to content

Social Justice: Expert witness cross-examination conundrum

There are various strategies available to counsel in attempting to impeach an expert’s credibility. Cross-examination on the basis of prior inconsistent statements is a well-known strategy. As seen in the recent Jian Ghomeshi acquittal, this technique is a powerful weapon in attacking the credibility of any witness. Another strategy is cross-examination to establish bias, attempting to establish the witness’ partisanship.

These strategies may fall short. Counsel may be unable to locate any prior statements. The expert may not have made or published prior inconsistent statements. Moreover, bias is difficult to establish even where the expert has a long history of providing evidence to one side in litigation.  

But what of adverse findings of credibility made against an expert in prior judicial determinations? May counsel use such findings in cross-examination to attack the credibility of an expert?  

That issue came before the court in Bruff-Murphy v. Gunawardena, 2016 ONSC 7. One of the defence experts had been the subject of three prior judicial determinations rejecting his evidence for reasons of partisanship. The expert had a history of stepping outside his role as an impartial witness and had become an advocate for the defence.

Based on past precedent, however, the court refused to permit cross-examination based on the prior judicial determinations. In the absence of a jury, such a finding is of little significance as the trial judge will be aware of the prior determinations. However, prohibiting such cross-examination may be of great significance in a jury case as the jury would not be aware of the prior determinations. The jury may place undue reliance on the expert’s testimony, unaware of the expert’s history.

The rationale for not allowing such cross-examination was stated in an Ontario Court of Appeal decision, R. v. Ghorvei (1999), 46 O.R. (3d) 63. Such cross-examination is not permitted as the prior judicial determination “is, in essence, no more than an opinion on the credibility of unrelated testimony given by this witness in the context of another case.”

Why the opinions of other judges are not worthy of consideration puzzles me. Surely, an opinion of a judge rejecting an expert’s testimony is deserving of some consideration. Surely, every adverse determination is a potential red flag concerning the partisanship of the expert. But I understand there may be a practical issue in attempting to utilize the prior determinations. Doing so may require a consideration of the foundation of the prior determinations. Still, how difficult is it to place a prior determination in context?  

Indeed, in Ghorvei, the court was able to place the prior determination in context, concluding it was unfounded.

Allowing cross-examination would thus have been highly prejudicial. But the witness in the Ghorvei case was not an expert witness who was being paid to provide his testimony and there was only one prior determination. Should the Ghorvei reasoning apply to expert witnesses who have suffered several prior adverse determinations? I pose this question in the context of two inquiries, both of which focused on the problem of partisan testimony by biased or hired-gun expert witnesses: Justice Coulter Osborne’s “Report on Civil Justice Reforms” (2007) and Commissioner Stephen Goudge’s “Inquiry into Pediatric Forensic Pathology in Ontario” (2008).

The Osborne report referred to an expert evidence working group complaining “that too many experts are no more than hired guns who tailor their reports and evidence to suit the client’s needs.”

Rule changes were implemented in 2010 in an effort to fix the problem. Yet the problem of partisan expert witness testimony remains. Judges and tribunals continue to criticize the partisan experts appearing before them. Even Justice Douglas Cunningham’s review of the SABS dispute resolution system in 2014 commented on biased expert assessments. We could leave the problem to the respective governing bodies for each discipline of expert. However, we have seen how that has worked, or rather not worked, as the problem of partisan experts continues seemingly unabated. We could advocate for beefed-up codes of ethics and more stringent discipline, but those are matters outside the jurisdiction of the legal profession.

There are no easy solutions to the problem of partisan experts. In an ideal world, experts who testify or provide reports for litigation would adhere to their oath to provide unbiased impartial testimony/opinions. But we don’t live in such a world.  

One partial solution may be to loosen the rules by permitting cross-examination based on prior judicial determinations. Perhaps the threat of such cross-examination will cause some experts to refrain from partisanship. Perhaps such cross-examination will expose partisan experts to juries. I understand that some judges make mistakes. A judicial determination may be erroneous. However, the existence of multiple judicial rebukes is surely worthy of some consideration. And, yes, I understand that just because an expert acts in a partisan manner in one case doesn’t mean she will do so in the next case. However, having acted in a partisan manner in one or more cases, where is the harm in having the expert justify himself in the context of the prior determinations?

I’d go a step further. I’d set up an expert witness database. Every time an expert testifies or provides a report for use at trial, an entry would be made into the database indicating the nature of the testimony or report, which side retained the expert, and the nature of any judicial determinations made concerning the testimony or report. This database would be open for public view to the general public. Perhaps the miscarriage of justice that occurred in the Bruff-Murphy action would have been avoided had the defence expert been cross-examined on his three adverse judicial determinations.


Alan Shanoff was counsel to Sun Media Corp. for 16 years. He currently is a freelance writer for Sun Media and teaches media law at Humber College. His e-mail address is ashanoff@gmail.com.

  • Assessment companies....

    Ian Little
    Insurers often use companies to deliver multi - disciplinary assessments which compounds the problem. Opinions favourable to the insured are downplayed or filtered out and in some cases the expert's own reports are changed to keep the insurer happy and the money rolling in.
  • no easy solutions to the problem of partisan experts

    Rhona DesRoches
    If the evidence is flawed there can be no justice. Bruff-Murphy and Daggitt v Campbell are a good demonstration of the costs of a failing justice system to victims. A system will have to be created to get medical opinion vendors in the middle and ensure competency without bias. We need medical report/examination standards along with expert testimony because where it starts is with the reports and where insurers get on the denial train. It does matter who is footing the bill for the medical evidence and that ability to hire means choosing that vendor who will do the best for insurers - meaning claims delays and denials. Insurers treat their own customers as if they are fraud artists and yet often some choose their supplier with an eye to paying more to deflate and deny than to address legitimate injuries. Our courts are overflowing with unpaid victims - the result of the problem medical reports and where half of all victims are denied in the first place.
  • whimsical judicial discretion?

    Brian Francis
    Asking a trier of fact to consider prior negative judicial comments aimed at medico-legal experts who sell testimony for a living can result in being called whimsical and idiosyncratic (see below). Go figure.

    “[22] … In my view, for the Plaintiff to succeed, there must be evidence of real or effective inappropriate conduct on the part of the nominee doctor, and not simply the whim or idiosyncrasies of the Plaintiff or similar views of his or her Counsel. …”

    (Wohlleben v. Dernisky) BC Supreme Court, Victoria Registry
  • If only

    Jokelee Vanderkop
    If insurers paid benefits to legitimate claimants rather than fight them for years on end, thereby forcing the injured into arbitration or until April 1, court, in order to receive what they deserve, we wouldn't be in this mess. The impartiality should begin with the insurance industry, followed by the assessment experts they hire. Rather than seek out assessors and expert witnesses who are fair and unbiased, insurers seek out the opposite in order to have them downplay injuries or outright deny legitimate claims in order to save insurers money. Insurers are more adept at treating claimants fraudulently than organized crime is at ripping off insurers. With organized crime it is sporadic, with insurers wrongful denials are consistent. It must pay because they've been doing it for years.
  • wilfully blnd triers of fact

    Brian Francis
    Following the inquiry into the systemic harm caused by the woefully inept expert opinion evidence of Dr. Charles Smith,Justice Goudge wrote that "the first mistake" was that lawyers and judges failed to pay attention to Justice Dunn's negative comments in an early decision. Why, in the context of criminal justice, are prior judcial warnings of an experts bias or lack of competency important (ie. Justice Dunn's); but in the Ontario civil justice (personal injury) context judges have stated that prior negative findings of bias (or lack of competency) will almost always be irrelevant? How is it possible an expert can be found to have been biased in several cases and yet judges are happy to perpetually throw the dice on the notion that prior findings of bias aren't sufficient "proof" the expert will be biased in the next case? If it were the judges rather than injured litigants paying the price for this sort of judicial gambling; this sort of obtuse gatekeeping wouldn't be so enduring.
cover image

DIGITAL EDITION

Subscribers get early and easy access to Law Times.

Law Times Poll


Lawyers have expressed concerns that of 38 justices of the peace the province appointed this summer, only 12 have law degrees. Do you think this is an issue?
RESULTS ❯