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Expert witnesses can win or lose your personal injury case. Whether helping to verify a claim for the injured party or refuting a claim for the defense, expert witnesses regularly testify in personal injury cases. So, what is an expert witness? How could a personal injury expert witness affect your case? This article answers these and other common questions about the role of an expert witness in a personal injury case.


What is the Role of an Expert Witness in a Personal Injury Case?


Expert witnesses regularly play a role in personal injury cases. An expert witness is someone with extensive knowledge or expertise in a field relevant to any part of the personal injury case.

In nearly all cases that go to trial or arbitration, both the injured party (the plaintiff) and the defense call one or more expert witnesses to support or refute the claims in the case. They are not eyewitnesses to the case. The role of an expert witness in court is to testify about a specific subject, not to give testimony about the moment of the incident.


What Types of Expert Witnesses Are There?


Expert witnesses are used to provide evidence for areas where a layperson, i.e. average person, cannot provide such evidence.  The layperson lacks the expertise, either the education, training, or experience, to provide such evidence.  Some of the more common types of expert witnesses you’ll see in personal injury cases include the following:


Liability Experts

Most personal injury cases come down to who is a fault or liable. Attorneys often call on experts to help prove who is liable based on the facts of the case. The nature and sometimes the location of the incident in question in the case will determine the type of liability expert needed.


Car Accident Expert Witness 

One of the most common expert witnesses in personal injury cases is someone with expertise in determining what happened in a car crash based on the evidence available. It could be anyone from a tire mark expert to an impact analyst. Common experts in this area include accident reconstructionists or biomechanics experts. 


Slip and Fall Expert 

Slip and fall expert witnesses may use their expertise to testify as to what happened in a disputed falling incident. They would analyze the crime scene and any evidence in the case and give their expert opinion on who is liable.  These often include human factors experts.  


Case Expert 

Sometimes understanding the unique circumstances of a case can require a significant level of knowledge in a specific discipline, like physics, for example. Attorneys may call in expert witnesses who can understand the details of the case and explain them to the judge or jury.

For example, an attorney might consult and even call an expert witness at trial to explain the relationship between speed, mass, and force and how it applies to a collision.


Physicians and Medical Experts

Doctors are also common expert witnesses in personal injury cases. They often testify about the extent of the victim’s injuries and the cost of the ongoing medical care needed. 


Brain Injury Expert Witness 

Cases in which the victim suffers a brain injury often require the testimony of a brain injury expert. They are the only people qualified to make a credible prognosis for the long-term impact of the damage.


Surgical Expert Witness

A surgeon may be needed as an expert witness in a personal injury case to explain any internal injuries a victim may have suffered.  The most common experts in this area are orthopedic surgeons and neurosurgeons.  The routinely get involved in personal injury cases.  


Mental Health Experts

Mental health experts will often testify on personal injury cases that involve a form of damages called pain and suffering. They help determine the mental anguish a victim suffers stemming from a traumatic event or debilitating injury. Sometimes victims develop conditions from which they can never recover. The judge or jury needs to take all of that into account when deciding to award damages. Mental health expert witnesses help them put the victim’s present and ongoing mental health outlook into perspective. 


In other cases, where a defendant was in a compromised mental state at the time of the incident, a defense attorney may call a mental health expert to testify. If they testify that the defendant’s mental state inhibited rational judgment, the state could absolve the defendant of liability.


What Requirements Are There to Be an “Expert Witness?”

The court has more rules about which topics an expert witness can testify than what makes someone an expert witness.


According to Federal Rule of Evidence 702, qualifying as an expert witness has just four requirements. 


  • The witness’s expertise will help the judge or jury understand the evidence or facts of the case.
  • The witness bases their testimony on sufficient, empirical information.
  • The witness formed the conclusions of their testimony through reliable methods with sound principles.
  • The witness has reliably used their expertise to apply those methods to the case.


Many people will fit these requirements for some subject in their life. Still, the practicality of being an expert witness is much more challenging.


When an expert witness provides testimony in a case, they may address only their area of expertise. The court must establish and accept the witness’s expertise early in the case, usually in the preliminary motions filed by the attorneys involved.  Along with the witness presenting papers showing their credentials, the attorney’s on both sides may ask the witness questions about their actual level of expertise. They may even require tests to prove expertise.


The witness’s background, reputation, work, and even choices in their personal life could come into question if they are relevant to the case. The testimony also can’t significantly depart from the regularly accepted consensus among the thought leaders in any particular discipline. Also, attorneys will attempt to discredit expert witnesses called by the opposition.


What Types of Personal Injury Cases May Require an Expert Witness? 

Expert witnesses come in all varieties, so almost any type of personal injury case will require one or more expert witnesses. However, some are a bit more common than others. The following types of personal injury cases often require an expert witness.


Motor Vehicle Accidents

Personal injury cases involving motor vehicle accidents often need expert witnesses to piece together all the physical evidence into a play-by-play of what happened during the accident.


Different types of accidents or various aspects of the same accident may require different experts. Cases involving a car crash may need an expert on mechanical failure and malfunctions. Cases with pedestrian accidents might require a traffic light programmer or surveillance camera technician to determine who was at fault. Commercial trucking accident cases may need experts on whatever materials the trucks were hauling to determine the dangers of any potential spills or leaks.


If you’ve been the victim of a motor vehicle accident, get help from an experienced personal injury attorney. They will know the right local experts to call to help your case.


Here are some other types of personal injury cases that may require expert witnesses. 

Brain Injury Cases

Brain injury cases often need testimony from doctors and mental health experts.


Wrongful Death Cases

Wrongful death cases could require a liability expert.


Nursing Home Neglect

Cases involving neglect could require medical experts or right of attorney experts.


What Advantages Are There For Using an Expert Witness?

Using expert witnesses in your personal injury case are essential to flesh out the elements you need to prove your case and help you prevail.  This includes:


  • They are a respected third party vouching for you.
  • They can counter testimony from opposing witnesses.
  • They can give a clear summary of a complex case.
  • They can provide their professional interpretation of the facts.


Those could be enough to sway the judge or jury in your favor.


Turn to the Strategic Legal Team at Swanson Lathen Prestwich, PC

The best way to get guidance on your personal injury case is to contact a lawyer. Get a free consultation with Oregon’s best personal injury attorneys. Contact us today or send us a question about your personal injury case