Ontario Superior Court of Justice Trials

Questions for Medical Experts to Meet the Threshold – Part 1 of 3

This is part 1 of a 3 part series on medical evidence to address threshold.

Personal injury lawyers know all too well that MVA clients must have a “permanent serious disfigurement” or a “permanent serious impairment of an important physical, mental or psychological function” in order to meet threshold (see section 267.5 of the Insurance Act).

It is commonplace to copy and paste into pleadings, mediation briefs and pre-trial conference briefs that the “plaintiff suffered a permanent and serious injury of an important function”.

The definitions of words such as “serious”, “important” and “permanent” can be found in Ontario Regulation 461/96 under the Insurance Act.

One aspect governing the admissibility of medical expert evidence at trial is whether advance notice of the opinion sought from the witness was provided prior to the trial, more specifically in their expert report.

Section 4.3 of Ontario Regulation 461/96 under the Insurance Act makes it mandatory to call a medical expert to give evidence on the following:

  1. The nature of the impairment;
  2. The permanence of the impairment;
  3. The specific function impaired;
  4. The importance of the specific function to the person;
  5. That the impairment is directly or indirectly sustained as the result of the use or operation of an automobile; and

In addition, section 4.3 of Ontario Regulation 461/96 makes it mandatory to call evidence:

6.  That corroborates the change in the function that is alleged to be a permanent serious impairment of an important physical, mental or psychological function.

In order to meet threshold, it is mandatory to ask your medical experts at minimum the following questions:

  1. What is the nature of the injury?
  2. Is the injury permanent?
  3. What function(s) is/are impaired?
  4. How important is/are the impaired function(s) to this specific patient?
  5. Was the patient’s injury caused by the automobile accident?

In addition, it is mandatory to call evidence from the plaintiff and/or family and friends to:

6.  Corroborate the change in function.  A line of questions in direct examination must therefore go out to the plaintiff and as many lay witnesses as possible that corroborates the change in function.

As one can imagine, the complexity of the Insurance Act and Regulations requires that medical experts be up to speed on the definitions found in the Insurance Act and Regulations in order for them to be able to answer the questions posed above in a manner that meets the definitions outlined at section 4.1 of Ontario Regulation 461/96.  A further discussion on what to address in answering these questions is available in our post “Ensuring Expert Medical Reports Address Threshold Issues” available by clicking here.

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