Ontario Superior Court of Justice Trials

Personal Injury Trials and Witnesses

Who the witnesses will be is surprisingly one of the most often overlooked issues until late in the course of litigation, usually when a pre-trial conference memorandum requires a list of witnesses. Lawyers should start working on their list of witnesses the day they open the file, just as an affidavit of documents is contemplated at the outset.

The are four main categories of witnesses at a personal injury trial: client(s), lay witnesses, treating experts and rule 53 experts. Below are a few ideas of who may be called to testify and some key areas for questioning to help in planning who the witnesses will be and the type of evidence they may need to give.

1. The Client

Obviously the client will testify. Some topics the client to testify about include:

  • Pre-accident health
  • Life before the accident (family, work, social, sports, interest, etc.)
  • The accident
  • The days following the accident, symptoms and initial assessments
  • Diagnoses relayed to the client by medical professionals
  • The course of treatment
  • Life after the accident (family, work, social, sports, interests, etc.)
  • Current status (symptoms, treatment, medication, etc.) and future plans

2. Lay Witnesses

Lay witnesses are very important in order to confirm what the client says about life before versus after the accident. Family members can be great, including spouses, siblings, parents, children, etc. Some family members may have Family Law Act claims.

Eyewitnesses to the accident may or may not exist. If they do, locking down witnesses statements is beneficial. An investigating Police Officer is likely to be a hearsay witness and not all that helpful.

Work colleagues can help support a loss of income. Friends can add a perspective to the client’s social life.

Some topics for lay witnesses (other than eyewitnesses) include:

  • Nature of their relationship to the client
  • Observations of the client’s life and abilities before the accident (at home, work, socially, etc.)
  • Observations of the client’s life and abilities after the accident (at home, work, socially, etc.)
  • Comments on medical treatment they are aware of

3. Treating Experts 

The Court of Appeal’s 2015 decision in Westerhof v. Gee Estate defines treating experts, such as the family doctor as “participant experts” not “fact witnesses” and therefore these experts can give opinion evidence.

Treating experts will include the family doctor, physicians and medical professionals from the hospital and treatment clinics, including anyone involved in medical imaging.

Topics for treating experts include:

  • Qualifications in terms of education and work experience
  • Pre-existing health (especially for the family doctor)
  • Examinations performed
  • Diagnoses and the rationale behind the diagnoses
  • The course of treatment and impact on the treatment
  • Prognosis

4. Rule 53 Experts

Rule 53 experts have a bad rap as hired guns, but some experts fulfill this role extremely well and remain as objective as possible in the circumstances. Rule 53 experts may address liability. They are most often used to establish damages and include a wide range of specialties to address physical and psychological injuries.  Financial experts are used to help quantify damages.

Topics for rule 53 experts include:

  • Qualifications in terms of education and work experience
  • Documents reviewed
  • Examinations performed
  • Diagnoses and the rationale behind the diagnoses
  • Prognosis
  • Opinions on specific issues such as threshold, CAT determinations, IRBs, etc.

Please click here to purchase a template witness list for use in plaintiff pre-trial conference briefs.

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