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When Does an Expert Lack Impartiality, Independence?

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In Cambie Surgeries Corporation v British Columbia (Attorney General), the court expressed concerns about the impartiality and independence of certain experts.

The plaintiffs sought to have certain provisions of the Medicare Protection Act declared unconstitutional. Patients, they said, should not be prevented from accessing private medically necessary healthcare, including private surgeries, when timely care is not available in the public system.

They did not claim that introducing a private tier of healthcare would reduce public system wait times.

The B.C. Supreme Court dismissed the claim.

In so doing, it had made several observations about the evidence of certain experts.

Generally, opinion evidence is not admissible in a legal proceeding.

An exception to this is expert evidence.

Expert evidence may be tendered when it is necessary to educate the judge on advanced scientific issues.

An expert must be qualified on the subject matter of his or her evidence.

For example, an economist may provide an expert opinion on an economic issue within his or her expertise. An economist cannot opine on an issue of medical causation.

The Rules of Court state that an expert “has a duty to assist the court and is not to be an advocate for any party.”

An expert must also certify in any report that he or she is aware of that duty, made his or her report in conformity with that duty and will provide oral testimony in conformity with that duty.

Relying on an Ontario decision, Bedford v. Canada, and a British case, the court in Cambie summarized the role of an expert:

  1. Expert evidence should be, and be seen to be, the independent product of the expert uninfluenced as to form or content by the exigencies of litigation.
  2. An expert witness should provide independent assistance to the court by way of objective unbiased opinion in relation to matters within his or her expertise. An expert witness should never assume the role of an advocate.
  3. An expert witness should state the facts or assumptions upon which his or her opinion is based. He or she should not omit to consider material facts which could detract from his or her concluded opinion.
  4. An expert witness should make it clear when a particular question or issue falls outside his or her expertise.
  5. If an expert's opinion is not properly researched because he or she considers there is insufficient data available, then this must be stated with an indication that the opinion is no more than a provisional one. If an expert witness who has prepared a report could not assert that the report contained the truth, the whole truth and nothing but the truth without some qualification, that qualification should be stated in the report.

The court also adopted the following summary of the approach to expert evidence, which seeks to remedy concerns that include bias and advocacy:

  1. the theory or technique utilized by the expert must be reliable, and used in a manner that is reliable;
  2. the expert must keep an open mind to a “broad menu of possibilities” (not be biased);
  3. the expert must be objective and comprehensive in collecting evidence -- including rejecting information not germane and transparent about the information and influences involved; and
  4. the expert must proffer more than the mere opinion, including the complete reasoning process, shortcomings and fair guidance on the confidence in the opinion.  

In determining how much weight to give to expert evidence, many factors are considered. They include the expert’s qualifications and expertise, the expert’s independence and impartiality, the validity and strength of the logic and methodology followed and the extent to which the expert’s methodology and opinions are supported and consistent with the relevant scientific evidence (including that cited by the expert).  

Whether a witness has a pecuniary interest in the proceeding can, but does not necessarily, undermine a witness’s credibility. The full context is considered.

In Cambie, several of the experts received earnings from the corporate plaintiffs.

There were also significant problems with much of the expert evidence tendered by the plaintiffs.

Although the reports contained the required certificates, there were indicators that their roles as experts were not approached in a manner consistent with those certificates. This included:

  • receiving “confidential” partisan communications from another physician (who himself could not provide evidence because he lacked impartiality) that were clearly intended to influence the experts. These communications were highly problematic because:
    • They personally attacked some of the defendant’s experts. It was not possible to say that this did not influence how the experts read the defendant’s reports;
    • They made numerous unsupported assertions of fact, which were adopted (in some cases almost verbatim) into the expert reports, and without any indication that the experts independently verified those assertions;
  • One expert declared that he was a “passionate advocate” for private medical care;
  • That expert also admitted that he cited only articles that supported his views, despite being aware that other studies and reports contradicted his opinions;
  • One expert admitted to not having conducted his own independent research and could not even say if he had reviewed the materials provided to him;
  • Plaintiff’s counsel made substantive changes to some of the reports;
  • The experts did not appreciate their duties to the court.

The judge gave no weight to the evidence of at least six of the plaintiff’s experts.

The physician’s communications “so tainted their evidence” that the court could not be confident in their independence. 

In addition, the court observed that the reports lacked clear underlying methodology that could be tested or evaluated. They made bald assertions without referring to any supporting literature or scientific evidence. Some opinions were based on personal anecdotes that could not be tested.

This case illustrates the importance of approaching expert evidence with great caution. Failing to do so may result in the evidence being completely, and publicly, rejected.

This is a modified version of a November 1, 2020 article appearing in online publications including the Kelowna Capital News. The content of this article is intended to provide very general thoughts and general information, not to provide legal advice. Advice from an experienced legal professional should be sought about your specific circumstances.  We may be reached through our website at inspirelaw.ca