The longstanding principle that “there is no property in a witness” allows any party in an action to interview the same witness and to admit evidence from the same witness in court. While this principle is often practiced in the context of fact witnesses, it is less common to see opposing counsel retain the same expert in an action. Although uncommon and perhaps controversial, our courts have recently confirmed the tenability of this practice. In this fourth article in the series on expert evidence, we highlight two decisions where our courts have allowed counsel to use the same expert at different stages in a proceeding.

In 2015 in Charlebois v SSQ, Life Insurance Company Inc., 2015 ONSC 2568, a dispute over insurance benefits, SSQ sought leave to appeal a motion judge’s decision allowing counsel to continue representing Charlebois and to continue using experts whom SSQ had previously retained. SSQ argued that the two experts, an occupational therapist and a psychologist, were privy to confidential information they had received from SSQ. These experts were hired by SSQ to provide treatment to Charlebois before SSQ terminated her benefits under a disability insurance policy. SSQ argued that to prevent potential unfairness from the use of privileged information, Charlebois’ counsel should be removed.

The Divisional Court started its analysis by confirming that there is no rule prohibiting a party from retaining an expert who another party in the litigation previously retained in the same dispute. The only qualification, the court said, is that the expert must not disclose confidential information and information which is privileged. If this happens, fairness may require the removal of counsel who retained the previously involved expert witness. The inquiry for assessing the proprietary of an opposing party retaining the same expert is:

(1) Has the moving party shown that the expert received relevant confidential information?

(2) Has counsel for the responding party shown that he or she did not receive the confidential information?

(3) Is there a risk that the confidential information will be used to the prejudice of the moving party?

(4) Is removal from the record the appropriate remedy?

Applying these principles to the case at bar, the Divisional Court upheld the motion judge’s decision to allow Charlebois’ counsel to continue as the lawyer on record, and to allow Charlebois to continue using the occupational therapist and psychologist as expert witnesses. SSQ failed to prove that the experts were in possession of privileged information.

As noted, although permitted, the practice of retaining the same expert as the opposing party is likely to be viewed as highly suspect by counsel. Even the court itself in Charlebois acknowledged as much. In writing the decision, Justice Ellies stated, “I would not like to be understood as encouraging this practice”, that is, the practice of opposing parties retaining the same expert. Justice Ellies recognized the perceived unfairness in this practice.

Although not encouraged, the principle of “no property in an expert witness” remains. Also in 2015, in Ontario (Municipal Affairs and Housing) v Niagara (Region), 2015 CanLII 51661 (ON OMB), two developers jointly moved before the Ontario Municipal Board for an order disqualifying an opposing developer’s expert witness. The expert, an engineering consultant, had previously opined on the same matter for the moving developer.

The Municipal Board started its analysis by upholding the principle that there is no property in an expert witness. However, it cited a 1979 English case, Harmony Shipping Co. v. David:

If an expert could have his hands tied by getting instructed by one side, it would be very easy for a rich client to consult each of the acknowledged experts in the field. Each expert might give an opinion averse to the rich man, yet the rich man could say to each, "Your mouth is closed and you cannot give evidence in court against me' .... Does that mean that the other side is debarred from getting the help of any expert evidence because all the experts have been taken up by the other side? The answer is clearly NO ... There is no property in an expert witness as to the fact he has observed and his own independent opinion of them.

Applying this principle, the Municipal Board refused to disqualify the responding party’s expert since there was no claim by the moving parties that the responding party received confidential information and the expert swore that he did not disclose any confidential information.

Charlebois v SSQ, Life Insurance Company Inc. and Ontario (Municipal Affairs and Housing) v Niagara (Region) demonstrate that it is legally tenable for a party to obtain an opinion from an expert who another party in the litigation previously employed in the same dispute. However, these cases also demonstrate the drawbacks of this practice. The perception and possibility for privileged information to be disclosed could give rise to another legal dispute, not only about the admissibility of the expert’s opinion, but also about counsel’s ability to remain on the record.

Nevertheless, there will be circumstances in which the benefits of employing the same expert as another party outweigh the risks. This may be the case for lawyers practicing in smaller communities, when a niche expertise is required, or when the expert has a pre-existing relationship with the party, such as the health professionals in Charlebois. If a party ultimately decides to use the same expert as another party, counsel should carefully explain to the client the risks of doing so, and explain to the expert his or her obligation not to use or share confidential or privileged information.

This article originally appeared on The Lawyer's Daily website published by LexisNexis Canada Inc.