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The Use of Expert Witnesses in Personal Injury Cases

Written by Berkowitz

expert witness

Unlike an ordinary witness, an expert witness offers opinion evidence rather than fact evidence. For example, an ordinary witness might testify that he saw the defendant’s pickup truck run a red light and collide with the plaintiff’s vehicle. An expert witness, on the other hand, might testify that the plaintiff’s chronic back pain was caused by the accident or that the plaintiff will not be able to return to a normal work schedule for at least two years.

Although expert witnesses are retained by one side or the other and are almost always paid for their services by the side that retains them, it is considered highly inappropriate for a witness to act as an advocate for the side that retained him – he is expected to offer his neutral, unbiased opinion on the matter for which he was retained.

Nevertheless, any competent opposing lawyer will certainly bring to the court’s attention the fact that the witness is being paid. If acting as an expert witness is his full-time job, the opposing lawyer should bring that fact to the court’s attention as well – if for no other reason than to encourage the court to doubt whether the witness’s opinion is truly unbiased. Normally, however, this formality does little to discredit the testimony of an expert witness.

Court Supervision

Most personal injury cases are resolved through private settlement. Although expert witnesses are frequently used to gain advantage in settlement negotiations, it is at trial where expert testimony is particularly important. A court will not allow an expert witness to testify unless he meets certain qualifications:

  • He must have sufficient credentials to qualify as an expert in the field in which he will testify (a Ph.D. in physics, for example).
  • His expert opinion must be the result of an appropriate application of his specialized knowledge to the relevant facts and assumptions.
  • The opinion evidence that he has been retained to offer is relevant, reliable, and helpful to the trier of fact (typically a jury, but sometimes a judge).

Surmounting the foregoing obstacles accomplishes nothing more than to allow the expert to testify. Ultimately, it is up to the trier of fact to decide whether the expert is credible and to what extent his testimony should be relied upon.

Testifying Experts vs. Consulting Experts

A party to a personal injury case will typically retain an expert witness for one of two possible functions: to testify in court (as a testifying expert witness) or to provide behind-the-scenes advice (as a consulting expert).

If the expert is retained as a testifying expert witness, the court and the opposing party must be notified of the expert’s name, address, employer, field of expertise, subject matter of testimony, opinions to which he will testify, and the basis for his opinions.

Under Section 13-4(c)(1) of the Connecticut Practice Book, a testifying witness can be subpoenaed for a deposition prior to trial and he must submit to cross-examination by the opposing party’s lawyer during the deposition. Although the opposing party cannot require a testifying expert witness to answer written interrogatories, the witness is entitled to help the party that retained him answer any interrogatories within his field of expertise.

If the expert is retained as a consulting expert, on the other hand, the retaining party is not normally required to inform the opposing party of his identity or even of the fact that he was retained at all (certain exceptions apply to this rule). A consulting expert cannot be compelled to participate in a deposition, and he need not answer written interrogatories.

Types of Expert Witnesses

Since expert witnesses are used for many different purposes, they come in many different varieties, including (but not limited to):

  • Accident reconstruction specialists: Used to reconstruct the sequence of events that led to an accident and to a particular claim of damages (traumatic brain injury, for example).
  • Medical experts: Used to testify to the cause or seriousness of an injury, or (in a medical malpractice case) to the standard of care that the defendant health care provider was obligated to meet.
  • Psychology experts: Used to testify to the validity of claims of pain and suffering, emotional distress, and other noneconomic damages.
  • Scientific/Engineering experts: Used to testify on highly technical scientific or engineering matters, such as whether a particular consumer product was defective or unreasonably dangerous, to identify a defendant based on DNA tests, etc.
  • Vocational rehabilitation experts: Used primarily to testify on the amount of future lost earnings that are likely to be suffered by the plaintiff as a result of the injury.

Vetting Your Expert Witness

One way of locating an expert witness is to consult the Connecticut expert witness directory; another way is to seek the assistance of a seasoned personal injury attorney who has worked with many expert witnesses before. Not all expert witnesses are created equal, however, and one of the most effective ways to ruin an otherwise strong case is to select the wrong expert witness because you did not thoroughly vet him before you retained him.

The Internet is full of little-known ways to research the background of a potential expert witness, and your attorney should know about them – because disaster could be waiting if he doesn’t know but the opposing party’s lawyer does. The following are some of the questions you are going to need to answer about any potential expert witness you are considering retaining, especially if he will testify.

It is also important that you “vet” the opposing party’s expert witnesses – if you can find a way to discredit their testimony, your case could be greatly strengthened.

Has the Expert Misrepresented His Credentials?

It’s a good idea to check sites such as LinkedIn to make sure that the expert’s credentials there match up with the credentials he presented to you. Don’t just search online – telephone or email his university or his employer, for example. If your expert’s credentials have been falsified or exaggerated, a nasty surprise could await you at trial.

Has the Expert Made Damaging Comments on the Internet?

Even blog comments and spoken words on podcasts are locatable and discoverable, as is material that was once on the Internet but has since been deleted. Pay attention even to comments that are unrelated to the expert’s testimony (a racial slur uttered in a blog comment, for example), because such comments might be admissible as evidence under certain circumstances.

Is Your Expert Subject to an Undisclosed Conflict of Interest?

In some cases, for example, corporate records might reveal financial interests held by your witness that add up to a conflict of interest. The SEC’s EDGAR site is a good place to start researching corporate records. An undisclosed conflict of interest could result in the disqualification of your expert or, worse yet, a meltdown during cross-examination.

What Is Your Expert’s Track Record in Previous Cases?

If your expert has testified at trial before, as most expert witnesses have, it is possible that his testimony may have been allowed or disallowed on numerous occasions or that the parties for whom he testified exhibit a distinct pattern of winning or losing their cases. The Daubert Tracker can help you perform this type of research.

Has Your Expert Published Extensively? Has He Authored Anything That Could Embarrass You or Contradict His Own Testimony?

If your expert has published extensively, the content of these publications might provide a strong clue as to how effective his testimony might be and how easy it might be for the opposing party to discredit him (by discovering a publication he wrote coming to a conclusion that is the opposite of the one he is testifying in support of, for example).

Pitfalls for the Unwary: Common Expert Witness Mistakes

The following are only a few of the most common mistakes made by expert witnesses:

Recording His Thoughts

If your expert witness will testify, almost anything he writes down could end up in the hands of the opposing party. Suppose, for example, that your expert emails your lawyer expressing concern at some of the weaknesses in your case. The opposing party could potentially subpoena those emails and use them to discredit your expert’s testimony at trial. Even his personal notes could be subpoenaed. Telephone conversations, however, are generally safe.

Basing His Opinions on Facts Provided by Your Attorney

An expert witnesses’ opinion is expected to be unbiased, no matter who retained him or who is paying him. One mistake commonly made by expert witnesses is the slothful reliance on information provided by the lawyer who retained him. The expert needs to check the facts for himself, from neutral third-party sources and not from an advocate such as a lawyer.


An expert witness is expected to report his findings objectively rather than advocate for the party who retained him the way a lawyer does. If his testimony comes off sounding like advocacy, the jury is unlikely to give it much credit – indeed, the judge may even disqualify his testimony.

Testifying in Obscure Technical Jargon

Although under certain circumstances, confusing a jury with obscure technical jargon can be useful as an unethical “black hat” tactic, under the vast majority of circumstances, it is patently counterproductive. The expert should speak as clearly as possible with the aim of being understood by jurors who are not experts in his field.

Dirty Tricks Archive: The Expert “Screen”

In basketball, a screen is used to separate a defender from an offensive player by interposing another offensive player between the screened player and his defender. Something similar to this happens when two parties to a lawsuit are selecting expert witnesses in preparation for a battle in court or at the settlement table.

The way it works is that an attorney for one side will retain a well-known expert in a field relevant to the case, not because he wishes to use that expert himself, but because he wants to prevent the opposing party from using him. Once retained by one side, the witness cannot work for the opposing party, even in a passive consulting role, because of the conflict of interest that would result. This tactic is unethical, but it is not at all uncommon.

Contact Berkowitz Hanna Today

If you have been injured under circumstances that you believe point to someone else’s culpability, call Berkowitz Hanna today or contact us online for a free initial consultation. We serve clients from throughout Connecticut from our offices in Stamford, Bridgeport, Danbury, and Shelton.