What is an Expert Witness in a Lawsuit?

March 28, 2017

Expert Witness

Why do Expert Witnesses Matter in Lawsuits?

During a lawsuit there are times when it is critical to have an expert witness testify on your behalf. Expert witnesses are people with specialized knowledge in a specific area. They must have the background to show the court that they have the required knowledge to be an expert. Common types of experts in personal injury suits include:

  • Doctors
  • Nurses
  • Mechanics
  • Accident Reconstruction
  • Scientists
  • Engineers
  • Pharmacists

Perhaps you have seen the movie My Cousin Vinnie? Do you remember how Vinnie called on Mona Lisa Vito to be an expert witness to help in the case? You might not think of Ms. Vito as an expert witness, but clearly she was an expert witness on the area in question, namely cars and tires.

Lay Witness Versus Expert Witness

Accident Reconstruction Expert

Accident reconstruction experts are used to offer an opinion about rate of speed, cause of accident and other useful information.

Most witnesses are lay witnesses. A lay witness is a person who knows something about what happened in the case because they experienced something related to the incident about which they testify. An expert witness, however, is someone who offers an opinion. For example, if you are in a car accident, an expert in accident reconstruction can go to the scene, look at the tire marks, look at the damage to the car, and offer an opinion about how fast someone was driving. A lay witness, however, can only testify to what they actually saw when the crash occurred. They cannot offer an opinion.

Some Lawsuits Require Experts

Expert Witness

An expert witness is someone with specialized knowledge related to the issues in a case. If you were hurt by a doctor, you need a doctor to testify on your behalf.

Not all lawsuits require expert witnesses. Others do. In those cases, without an expert witness, it is impossible to prove your case. In some suits, the law requires an expert. You cannot go forward with a suit without an appropriate expert.

For example, in order to pursue a medical malpractice case, your lawyer must obtain an expert who agrees that the doctor who hurt you violated the medical standard of care and in doing so, caused your harm. The standard of care is the level of care expected under a specific set of circumstances.

We all have standards of care that we must follow based on what we are doing at a given moment. For example, we must drive our cars with a certain level of care. Based on their own knowledge, a jury is capable of determining whether we followed that standard. No expert witness is necessary. In other situations, the average juror will not be able to ascertain what the standard of care is, and whether the violation of that standard rises to the level of negligence, without the help of an appropriate expert. In these types of cases, an expert witnesse is required.

Here, attorney Dennis Abrams explains standard of care in a medical malpractice case.


Lawyers, Expert Witnesses and Lowenthal & Abrams

Expert witnesses are people who are specialists in their areas. As a result, the lawyers who represent clients in areas that use expert witnesses must know how to properly examine and cross examine these experts. It is critical that you retain the right lawyer to help you. A lawyer who knows how to work with experts, knows what questions to ask, and also, knows how to stand up to the opposing expert during litigation. Lowenthal & Abrams has 15 litigators. We know the law and we know how to handle experts. Contact us today for help with your complex lawsuit.



national trial lawyers
philadelphia life awesome attorneys
Suburban life
newsweek top attorney
ASLA award
million dollar advocated forum 
million dollar advocated forum 
bbb accredited business
Silver Badge
best personal injury lawyers in Philadelphia 2022 award
How Can We Help?

Contact us for a FREE consultation. No fee unless compensated.

    Bala Cynwyd
    Cherry Hill
    New Brunswick
    New York