An Expert Witness Can Be the Key to Your Personal Injury Case

How to find the expert witness you need to present a case?


An “expert witness” is sometimes called in for a legal case because they have the proper training and experience to contextualize evidence. This experience could help the judge and jury make a decision. See what qualifies someone as an expert and what you can contribute to a trial.

Why do you need an expert witness? Sometimes an expert witness is called in to testify on evidence that requires specialized experience, education, or understanding.

We hear more about forensic or medical experts, although a specialist can be called in for almost anything. In many cases, what attorneys will look at most closely with regard to expert testimony is whether the person is qualified as an expert.

Often each side will call in its own expert and each may have a different opinion on the available evidence. When that happens, attorneys often try to discredit the opposing attorney's expert. It can get dirty!

Who can be an expert witness?


Within the Federal Rules of Evidence (FRE), there are details on who can be an expert witness. These laws also apply in state courts. In general, an expert should have the following in a specific field:

  • Knowledge
  • Ability
  • Education
  • VIP experience
  • training


Restrictions on expert witness testimony


A Witness only allowed to testify about what they have actually observed. An expert witness is generally allowed to provide his professional opinion on a piece of evidence. FRE Article VII, Rule 702 has four requirements for expert testimony:

  1. The expert's scientific, technical or other specialized knowledge will help the court to understand the evidence and determine a fact in question.
  2. Expert testimony is based on sufficient facts or data.
  3. Testimony is the product of reliable principles and methods.
  4. The expert has reliably applied these principles and methods to the facts of the case.


Federal law also includes the Daubert Standard ( Daubert v. Merrell Dow Pharmaceuticals, Inc. ) for the admissibility of expert testimony. This is used when a party seeks to exclude expert testimony on the grounds that the witness or evidence is not properly qualified. This is called a "Daubert challenge."

The five questions to ask when applying the Daubert standard are:

  1. Can the theory or technique in question be tested?
  2. Has the theory been peer-reviewed and published?
  3. What is the known or potential error rate for this theory or method?
  4. Are there existing and maintained standards to operate the method?
  5. Has the method attracted widespread acceptance within a relevant scientific community?


While Daubert is the rule in federal cases and in most states, there are still some states that use an older standard. Your state court could use the standard Frye ( Frye v. US ), which asks whether expert opinions are based on generally accepted techniques in the scientific field. Daubert goes a bit further by ensuring that the testimony actually adheres to the concepts of Rule 702.

Different types of expert witnesses.


If your case is complicated and involves technical evidence, your attorney will find an expert witness who is specifically trained on the subject. Most cases require expert witnesses who fall into the following categories.

Medical expert


Medical experts are more prevalent than any other type of expert in court proceedings. A medical expert can be a physician, but it can also be a nurse, technician, or medical assistant who specializes in the specific field that is relevant to the evidence or your case. Often times, medical experts include dental experts or other scientists who can analyze the data presented by one of the parties.

Forensic expert


A forensic expert is sometimes a medical expert, but not always. This person is an expert regarding some science related to the case (often criminal, but not always). A forensic expert can be someone who analyzes ballistics, blood splatters, criminal behavior, and other material evidence. For example, if a party wants to prove that a fingerprint or fingerprint belongs to a specific person (or would rule out a specific person), they can call in a forensic expert who knows the science behind making that determination.

Financial expert


A financial expert will testify about accounting, fraud, tax evasion, and other financial crimes. These experts are primarily used in white collar crime trials.

Mental health expert


A mental health expert will be called in to testify about behavior, psychological profiling, or other mental fitness issues that may affect the case. This person is very similar to a medical expert, except that their testimony will address questions such as whether the person understood their actions, is clinically or criminally insane, or is of good opinion and can make decisions related to wills or other legal situations.

Vocational expert


This expert is generally reserved for Social Security disability benefits appeal hearings. A vocational expert will offer an opinion on whether the person is capable of working. For example, the Social Security Administration could use this testimony to prove and show that the person does not really need disability benefits.

How to find an expert witness


Fortunately, it probably isn't necessary.

A good lawyer reason is essential because they will already have an excellent list of expert contacts, or if they don't have one specific to your case, they can find one. Your job as a plaintiff in a lawsuit is to convey the facts to your attorney as completely and carefully as possible. It is your attorney's job to use helpful evidence and find experts who provide context that makes the evidence demonstrate what is needed for a successful legal proceeding.

The Personal Injury Lawyer Directory is a great resource for finding the right attorney for your case and in your state. This guide to getting ready to meet with your attorney for the first time will also provide information on what to expect, bring, and do to get the most out of that first meeting.