P.I. Ruling Clarifies Expert Rule

This is true

This is true

A recent Divisional Court decision offers clearer guidance on how the Rules of Civil Procedure apply to witnesses who testify as expert opinion witnesses.

Contradictory case law had created some confusion. Westerhof v. Gee adds a measure of clarity. The court found that, if they’re giving an account based on opinion rather than facts or observation, witnesses — such as treatment providers — must comply with Rule 53.03 of the Rules of Civil Procedure.

The rule deals with an “acknowledgment of the expert’s duty,” in order to give an account in court. The June decision found that the focus should be on the type of testimony being given, rather than the “label” the expert uses.

There is some concern that the Divisional Court ruling will add to the cost of personal injury litigation.

“If it is opinion evidence, compliance with Rule 53.03 is required; if it is factual evidence, it is not,” the court found, in refusing to admit the testimony of some experts who had not complied with Rule 53.03.

    53.03(1) A party who intends to call an expert witness at trial shall, not less than 90 days before the pre-trial conference required under Rule 50, serve on every other party to the action a report, signed by the expert, containing the information listed in subrule (2.1). O. Reg. 438/08, s. 48.


Westerhof v. Gee (Estate), 2013 ONSC 2093 (CanLII)

R. v. Collins, 2001 CanLII 24124 (ON CA)
“In the law of evidence, an opinion means an ‘inference from observed fact.’”