When you’re the victim of personal injury, it takes a team spanning multiple disciplines to help get you back on your feet. From a skilled personal injury lawyer to your treating physician, every specialist is critical in helping you recover and obtaining the compensation you deserve. 

Expert evidence providers in Ontario are the same. If your personal injury case advances to a certain point, you will likely rely on an expert to provide critical evidence for your personal injury claim. Who are these experts, and what do they do to help with your personal injury claim?

What is Expert Evidence? 

A witness provides expert evidence with specialized knowledge or expertise in a particular field. Experts’ specializations can range from medical to financial to accident reconstruction. What these experts have in common is that they help the parties (and, if the case goes to trial, the court) understand the complex or technical issues at play. 

Some examples where expert evidence might be used in a personal injury claim include: 

  • Hiring a psychologist to provide expert evidence on the psychological injury a plaintiff suffered following an accident; 
  • Hiring an economist to provide expert evidence on the range of future loss of income suffered by a plaintiff following an accident; or
  • Hiring an accident reconstruction specialist to provide evidence on how an accident occurred where liability is at issue. 

How Is Expert Evidence Used in Ontario? 

In Ontario, expert evidence is governed by the Rules of Civil Procedure, RRO 1990, Reg 194. Below, we’ll outline some of the key procedural considerations for expert evidence in Ontario personal injury claims. 

Obtaining Expert Evidence

During your personal injury claim, your personal injury lawyer will determine whether expert evidence will be needed and, with your direction, retain appropriate experts. 

Different expert witnesses will require different things from you when preparing their evidence. For example, if your lawyer retains a medical expert, you may need to attend a medical examination so that the expert can evaluate your symptoms and develop their opinion. In other cases, your lawyer may provide the expert with records relating to your claim. 

Ultimately, once the expert has the information they need, they will prepare a report opining on your case as it relates to their area of expertise. 

Requirements for Expert Reports

The Rules of Civil Procedure, RRO 1990, Reg 194 outline several requirements for expert reports. Specifically, expert reports must contain the following: 

  • The expert’s name and address; 
  • The expert’s area of expertise; 
  • The expert’s qualifications (including the education and employment experience relevant to their area of expertise); 
  • The instructions that the lawyer provided the expert concerning the personal injury claim; 
  • The type of opinion sought and the issues relevant to the opinion; 
  • The expert’s opinion regarding the issues and reasons for their opinion; and 
  • An acknowledgement of the expert’s duty. 

The Duty of Expert Witnesses

While we’ve talked a lot about what experts do for personal injury lawyers and their clients, the truth is that an expert’s primary duty is to the court. To that end, the Rules of Civil Procedure, RRO 1990, Reg 194 state that every expert must provide the following: 

  • fair, objective, and non-partisan opinion evidence; 
  • opinion evidence relating only to matters that are within their area of expertise; and
  • additional assistance to the court where reasonable to determine a matter in issue. 

This duty prevails over any obligations owed to the party who retained the expert. 

Service of Expert Reports 

The Rules of Civil Procedure, RRO 1990, Reg 194, require parties to serve expert reports on all other parties at least 90 days before trial. This rule allows the other parties to review the evidence and prepare their own expert evidence (if they decide it is necessary). This means that experts are retained well before a trial occurs in most personal injury claims to allow sufficient time for examinations and drafting of their reports. 

Expert Evidence and Rebuttal Reports

As the opposing party will receive your expert report well in advance of trial, they may decide to obtain a “rebuttal report” from another expert. For a rebuttal report, the opposing party will provide another expert with a copy of your expert’s report and other records and request that they prepare a report based on their findings. In essence, a rebuttal report allows an opposing party to seek a “second opinion” on what the evidence presented in the original expert report says. 

Admissibility of Expert Evidence

Obtaining evidence is one thing – but ensuring that your evidence is admissible in court is another matter. Admissibility of evidence refers to whether a particular piece of evidence can be considered by a court when making a decision. 

For expert evidence to be admissible in Ontario, it must meet a few criteria. Specifically: 

  • Relevance: The expert’s evidence must be relevant to the issues in the claim. Specifically, it must be directly related to a fact in an issue and capable of providing insight that is not within the knowledge and experience of the average person. 
  • Reliability: The expert evidence must be reliable. That is, the expert must have the necessary qualifications and expertise to provide an opinion on the subject matter and must be based on reliable methodology. 
  • Necessity: The expert evidence must be necessary to assist the court in making its decision. This means that the evidence must be crucial to the case and must provide information that could not be obtained through other means. 

If an expert’s evidence is found to be inadmissible, it cannot be presented to the court in whole or in part and cannot be used when the court makes its decision. 

Expert Testimony in Court

If your personal injury claim makes it to court, your personal injury lawyer will likely call your experts to provide crucial evidence to support your claim. While your lawyer will have the opportunity to examine the expert and walk through their report with them, the opposing party will also have an opportunity to question the expert – and to challenge their findings. 

Final Thoughts on Expert Evidence in Ontario Personal Injury Claims

Expert evidence is an important component of Ontario personal injury claims – especially in complex or technical cases. By providing their specialized knowledge and expertise, expert witnesses can help clarify personal injury claims that help the court make an informed decision. 

Skilled Personal Injury Lawyers Serving Ottawa, Cornwall, Kingston and North Bay

At Tierney Stauffer LLP, our skilled personal injury lawyers have years of experience representing personal injury victims against insurance companies to get full and fair settlements for our clients. When you work with our lawyers, we will work to ensure that you remain informed throughout the process and obtain the best possible compensation amount to help you move forward after the accident.

Call us at 1-888-799-8057 or contact us online to set up a free consultation with one of our experienced personal injury lawyers


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