What is an Expert Witness?

April 24, 2024
Jack Fine

You may have heard the term “expert witness” before, but many people outside of the legal field may not fully understand what that term means. Under Florida’s Rules of Civil Procedure, someone cannot just claim they are an expert in some field and be allowed to testify. The individual must meet strict standards before they can be certified as an expert witness, and expert witnesses are only allowed to testify about certain matters in a civil case.

Understanding the rules regarding Florida expert witnesses is crucial if you want to maximize your compensation following a personal injury. That’s why the Gainesville personal injury lawyers at Fine, Farkash & Parlapiano P.A. want to shed some light on what qualifies someone to be an expert witness and how expert witnesses are used. Keep reading to learn more.

Definition of an Expert Witness

An expert witness is a professional who possesses specialized knowledge, skills, education, experience, or training that is not common to the average person. These individuals are called upon in a trial to provide their expert opinion, helping judges and jurors understand complex technical or scientific issues that are relevant to the case. 

Expert Witnesses vs Lay Witnesses

The main difference between expert witnesses and other types of witnesses lies in the type of the testimony they are permitted to provide. Here are a few key differences:

  • Expert witnesses provide opinions or conclusions, while lay witnesses only testify about direct observations without interpretation.
  • Expert testimony is based on expertise, including evidence review and data analysis, whereas lay testimony is solely based on personal experiences.
  • Experts educate the court on complex matters, influencing outcomes with their knowledge; lay witnesses offer factual accounts to establish basic case facts.
  • Experts prepare through case-specific analyses and evidence review; lay witnesses rely on recalling events or reviewing statements.

Examples of an Expert Witness

Expert witnesses come from a wide array of professional backgrounds, each bringing their own specialized knowledge to a case. Their expertise is invaluable in providing clarity and insight into complex issues that are beyond the knowledge of the average juror or judge. Here are some common examples of expert witnesses: 

  • Medical Experts: Medical experts are often called upon to testify in cases involving personal injury, malpractice, wrongful death, or workers’ compensation. They can offer opinions on the cause of injuries or death, the quality of medical care provided, future medical needs, and the prognosis of injuries.
  • Real or Personal Property Value Experts: Real estate and personal property valuation experts determine the value of property or assets in cases of divorce, estate settlements, property disputes, and damage assessments.
  • Value of Services: Experts in various professions can testify about the reasonable value of professional services in disputes involving alleged overcharging or underperformance.
  • Accident Reconstruction Experts: Accident reconstruction experts use physics, engineering, and biomechanics to determine the causes and dynamics of accidents, including vehicle collisions and workplace incidents.
  • Physicists and Engineering Experts: Experts in physics and engineering can calculate the speed of vehicles, projectiles, or any other moving objects, often playing a role in criminal and civil cases.
  • DNA Experts: DNA experts analyze genetic evidence to establish connections between suspects and crime scenes, victims, or objects. Their testimony can be used in proving guilt and clearing the innocent.
  • Economists or Life Care Planners: Economists and life care planners provide financial analysis and long-term care assessments in cases involving severe injuries or chronic conditions. They estimate the economic impact of injuries, including lost wages, future earning capacity, and the costs associated with ongoing medical care and rehabilitation.

Types of Evidence an Expert Witness Can Use at Trial

Expert witnesses leverage a variety of evidence types to support their testimony and provide clarity on complex issues at trial. The types of evidence they might use include:

  • Physical Evidence: Objects or materials from the scene.
  • Digital Evidence: Data from computers, phones, or online sources.
  • Documentary Evidence: Records, emails, contracts, and medical records.
  • Demonstrative Evidence: Charts, models, simulations, and reconstructions.
  • Eyewitness Testimony: Interpretations of witness accounts.
  • Scientific Evidence: Results from tests or experiments.
  • Statistical Evidence: Data analyses, surveys, and studies.

How to Qualify as an Expert Witness in Florida

Florida statute 90.702 outlines the qualifications for Florida expert witnesses and how they can be used in civil proceedings. First, a witness can be considered an expert based on “knowledge, skill, experience, training, or education.” This is a fairly broad definition, but you want someone with a thorough background in whatever subject you are asking them to testify about. It also helps if the expert has published research in their field of study.

State law goes on to lay out the conditions under which an expert witness may be allowed to testify. The witness must be able to help a judge or jury understand the evidence or judge the facts of a case. Furthermore, an expert witness is only allowed to testify if:

  • Their testimony is based on sufficient facts and data
  • Their testimony is the result of reliable principles and methods
  • The expert witness has applied these principles to the facts of the case in a reliable manner

To determine if someone qualifies as an expert witness, the court will conduct a two-part test. First, they must determine if the subject in question merits testimony from an expert witness because it will help the judge or jury better understand the case. Second, the court will determine if the expert is qualified to testify in the case. Assuming these conditions are met, the witness may be allowed to testify.

Questions Used to Qualify an Expert Witness

Voir dire is the process through which the qualifications of an expert witness are established. This involves an initial examination by the party proposing the witness as an expert, followed by a cross-examination by the opposing side. The following questions are commonly used in court to establish an expert’s qualifications:

  • What is your educational background?
  • What degrees do you hold?
  • Do you have any professional licenses or certifications?
  • How many years of experience do you have in your field?
  • Have you received any awards or honors in your professional field?
  • How often have you been published in professional journals or publications?
  • Can you provide a summary of your professional experience related to the case at hand?
  • Have you previously testified as an expert witness, and if so, how many times?
  • Are you a member of any professional associations or societies?
  • How do you stay current with developments in your field?
  • Have you ever been denied expert status or had your testimony excluded in previous cases?
  • Can you explain the methodology or techniques you used to arrive at your conclusions in this case?

What Disqualifies an Expert Witness

The integrity of the legal system depends significantly on the credibility and reliability of expert testimony. However, not all experts make it to the witness stand. Some specific criteria and instances can disqualify an expert witness from testifying in a case: 

  • Lack of relevant expertise
  • Insufficient credentials
  • Bias or conflict of interest
  • Unconventional or unreliable methods
  • Poor communication skills
  • Previous disqualification
  • Ethical or professional misconduct
  • Failure to comply with legal procedures

Why an Expert Witness is Important

The role of an expert witness can be pivotal to the outcome of civil and criminal cases. Expert witnesses bring a level of depth and clarity to issues that require specialized analysis, which the average person—including judges and jurors—may not possess.

Through their testimony, expert witnesses present intricate details of a case, whether it involves medical malpractice, financial fraud, or personal injury. They apply their expertise to interpret evidence, reconstruct accidents, evaluate professional standards of care, and estimate damages, among other tasks. This analysis can make the abstract or technical aspects of a case accessible and comprehensible to those without a background in the expert’s field.

Moreover, expert witnesses lend credibility to the arguments presented in court. Their testimony is often seen as more objective and based on facts and principles within their profession. This impartiality can influence the decision-making process of the jury or judge, helping them to reach a more informed and fair verdict.

In many cases, the testimony of an expert witness can either support or refute key elements of a case. For example, a wrongful death expert witness’s analysis of how and why the death occurred can significantly influence the jury’s decisions on liability and damages in a wrongful death lawsuit.

Experts also play a role in the pre-trial phase, assisting attorneys in developing their case strategy, reviewing the opposition’s claims, and identifying the strengths and weaknesses of the evidence. Their early involvement can lead to more accurate case assessments and, potentially, to settlements that avoid the need for a trial.

How Fine, Farkash & Parlapiano Can Help

The personal injury lawyers at Fine, Farkash & Parlapiano P.A. in Gainesville have built strong connections with a diverse range of expert witnesses throughout the years. Our team is equipped with the expertise and resources required to engage highly esteemed experts who possess deep insights relevant to your case. We are committed to constructing a robust case for you and striving for the best possible result. For more information and to start with a free consultation, reach out to our Gainesville office today.


Florida Rules of Civil Procedure | The Florida Bar

90.702 Testimony by experts | The Florida Legislature 

Accident Reconstruction: How the Experts Can Help You Win Your Case | Expert Institute