Westerhof restores law around opinion evidence admissibility

In a recent blog post for the Ontario Trial Lawyers Association, Ottawa personal injury lawyer Najma Rashid highlights five notable points from Westerhof v. Gee Estate, 2015 ONCA 206 (CanLII), the Court of Appeal decision clarifying the admissibility of opinion evidence given by non-expert witnesses in the context of 2010 amendments to Rule 53.03.

“Westerhof restores the law to what it was before Rule 53.03 was amended,” writes Rashid, a partner with Howard Yegendorf & Associates LLP. “The Court of Appeal confirmed that Rule 53.03 was intended to apply only to ‘expert witnesses engaged by or on behalf of a party to provide opinion evidence in relation to a proceeding’ and not to treating health care practitioners and other non-party witnesses.”

Rule 53.03 sets out the requirements for introducing the evidence of expert witnesses at trial. The judge at trial in Westerhof had refused to admit the testimony of certain experts, finding they hadn’t complied with Rule 53.03.

Key elements of the OCA decision, writes Rashid, include:

– Treating physicians may give opinion evidence about diagnosis, prognosis and treatment rendered;

– The treating health care practitioner as a “fact” or “participant” witness;

– The “non-party” expert is also exempted from Rule 53.03;

– The decision underscores the importance and utility of serving s. 52 Evidence Act notices, in regards to treating doctors’ reports and MRI/radiology reports; and

– Treating physicians can give evidence about a plaintiff’s ability to work.

“The Court of Appeal’s decision has put to rest the panic and confusion caused by the trial and Divisional Court’s rulings in Westerhof, which significantly restricted the use of evidence by ‘participant’ witnesses such as treating doctors, thereby increasing litigation costs and almost negating the utility of s. 52 of the Evidence Act,” writes Rashid.