
A personal injury case might feature two types of witnesses: ordinary witnesses and expert witnesses.
An ordinary witness, such as an eyewitness, can testify to what they saw and heard without being allowed to offer much in the way of interpretation. An expert witness, by contrast, can provide their opinion concerning events they did not even witness, as long as their opinion falls within their area of expertise.
Qualifications of Expert Witnesses in an Illinois Personal Injury Case

There is no specific list of qualifications that applies to all expert witnesses. It all depends on the nature of the expertise possessed by the witness. In academic disciplines, a Ph.D. is typically required, but that is up to the discretion of the court.
In general, Illinois courts will look at:
- Academic qualifications
- Work experience
- Publications in academic or occupational journals
- Reputation among peers
- Professional awards
Other factors might also come into play.
Experience Testifying
Judges typically don’t care whether the witness has experience testifying, but lawyers certainly do. Will the witness wilt under intense cross-examination? A witness testifying for the first time might not conduct themselves well. A witness with extensive experience testifying, however, will probably handle themselves quite well.
Testifying Expert Witnesses vs. Consulting Expert Witnesses
Lawyers typically use expert witnesses in two ways: as testifying witnesses and consulting witnesses.
- A testifying witness testifies under oath at a deposition and/or a trial. Their testimony is considered admissible evidence. The opposing party’s lawyer will cross-examine them as well.
- A consulting witness might help a lawyer understand the issues in the case, educate them on the strength of their claim, or prepare a written report that will help the lawyer gain leverage in settlement negotiations.
Many expert witnesses have retired from their field of expertise and testify full-time.
Types of Expert Witnesses Used in Personal Injury Cases
There are almost as many different types of expert witnesses as there are types of personal injury claims. Following are some descriptions of the most commonly used expert witnesses.
Medical Experts
A medical expert can be any professional within the healthcare system, preferably one who is licensed. That might mean a doctor, a nurse, a hospital administrator, a physical therapist, or another professional. A medical expert must testify within their field of expertise—a cardiologist cannot testify on neurosurgery, for example.
You might use a medical expert to testify regarding the victim’s probable future medical needs, the amount of pain and suffering they are experiencing, the physical limitations they are likely to suffer, or whether full recovery is possible or likely.
A medical expert witness might testify on whether the defendant was medically negligent. If the patient is dead (as in a wrongful death case), a medical expert might testify regarding the cause of death.
Vocational Experts
Lost earnings are a major component of many personal injury claims, as is diminished earning capacity. Lost earnings refer to earnings already lost, while diminished earning capacity refers to the earnings the victim will likely lose in the future (if their injuries are permanent, for example).
A vocational expert can testify about when, if ever, the victim can return to work, whether they can undertake their former job duties, and whether vocational training can help them to undertake a new occupation.
Engineering Experts
An engineering expert can testify as to whether a product (that injured someone) is defective and whether it would have been economically feasible to manufacture the product to reduce its dangers. They can also testify as to whether the manufacturer should have known that the product was unreasonably dangerous.
Financial Experts
A financial expert can testify as to how much money you will need in the future due to, for example, occupational disability. They can also determine the value of future lost earnings in today’s dollars.
Mental Health Experts
There are many situations in which the mental health of one or more of the parties is an issue. A court might extend the statute of limitations deadline for a mentally incompetent personal injury victim, for example. A mental health expert can also testify as to whether someone has been restored to competency.
The Expert Witness Industry
Many experts have retired from their field of expertise and now testify full-time. Indeed, many companies specialize in providing expert witnesses to those who need them. In addition, most experienced personal injury lawyers maintain long-standing relationships with skilled and credible expert witnesses. Ask your attorney to help you find an expert witness if you need one.
These experts are not cheap, but they can greatly add to the value of your claim. If you use one in court, you can be certain that the opposing party’s lawyer will point out to the court that the witness is receiving compensation for their testimony. This rarely matters, however, because expert testimony is routine in many types of cases.
An Experienced Personal Injury Lawyer Should Be Able to Maximize the Effectiveness of an Expert Witness
An experienced personal injury lawyer can help you in several ways concerning expert witnesses. They can determine whether you need one. They can help you find a good one. They can help prepare the witness and exploit the witnesses’ knowledge skillfully in settlement negotiations, pretrial discovery, and at trial.
If your case is complex enough to need an expert witness, don’t try to handle it on your own. Hire the best lawyer you can find.