Bench + Bar of Minnesota

Retaining and using expert witnesses: A short primer

2024-03-wittnes-400By R. Don Keysser   

Your firm has been retained by a litigant in a civil action. From your prior experience, you realize that this will be a lengthy and complex case, involving a considerable amount of technical information outside your firm’s expertise.

At some point, ideally early in the process, you will need to decide whether to recommend to your client that you retain one or more expert witnesses to assist in the case. This decision can have a significant impact on your case, especially if the other side retains expert witnesses.

My own specific experience is in financial matters—defaulted financings, financial damages, shareholder disputes, and the like. But these comments apply to all situations in which understanding complex technical information is critical to the management of your case: medical malpractice, product liability, insurance fraud, insider trading, patent infringement, and financial damages, for example.

What is an expert witness?

Expert witnesses are seasoned experts in a specific area of specialized technical knowledge, such as doctors, engineers, accountants, bankers, and regulators. They have a deep understanding of the subject matter of your case.

As noted in U.S. Federal Rules of Evidence, Rule 702, “A witness who is qualified as an expert by knowledge, skill, experience, training or education may testify in the form of an opinion…” The underlying logic is that “[a]n intelligent evaluation of facts is often difficult or impossible without the application of some scientific, technical or other specialized knowledge… the most common source of this knowledge is the expert witness.…”

Expert witnesses assist the court as a source of this expertise, in the court’s capacity as the trier of facts. This raises an interesting tension in the position of expert: While experts are objective providers of technical information, assisting the court as the “trier of facts,” the experts are also retained and paid by one of the sides in the proceedings. This raises the potential for a conflict of interest, which ethical experts will understand and respect.

Finally, expert witnesses are not advocates for your client; that is your job. It is important to remember this when managing your experts. The following checklists are intended as a brief guide to the considerations involved in making decisions about expert witnesses.

How can experts assist you?

  • Bringing in specialized outside expertise about a specific industry or body of technical knowledge.
  • Assisting in formulating and analyzing the theory of the case—from an industry perspective rather than a legal perspective.
  • Assisting in formulating discovery requests for evidentiary materials.
  • Writing a detailed expert report outlining the opinions of the expert—based on industry knowledge, research, and evidentiary material—as to the facts of the case.
  • Assisting in structuring the questions for witnesses in depositions.
  • Rebutting the testimony of the other side’s expert witness; if they have one and you don’t, you are at a distinct disadvantage.
  • Explaining the case in nonlegalistic, nontechnical terms to the jury during trial.

How and when should you select expert witnesses?

  • Select experts early in the process of developing your case; they can be especially valuable in the initial stages of defining your case, requesting discovery materials, and framing questions for witnesses in depositions. Selecting experts early can give them sufficient time to undertake a detailed analysis, conduct industry research, calculate damages, and thereby develop a strong report; a rush job does your client no favors.
  • Select carefully. Solicit references and testimonials from other litigators; read the candidates’ reports from previous cases to avoid embarrassing changes of opinions; try to interview the prospects, in person or via Zoom, to get a sense of their ability to handle themselves in an adverse situation. Some experts have made video clips of themselves that you can review.
  • Consider retaining the experts initially as non-testifying consultants to get a feel for how you can work with them, and then shift them into the role of testifying experts if your particular court will allow that (some do, some don’t).

How should you manage your expert witnesses?

  • Discuss and clarify your expectations of the experts. Tell them how you view the case, what the key elements are, what you want them to focus on (and not to focus on). Discuss with them the specific opinions you are seeking. 
  • Discuss the anticipated timeline for the case (in particular, when you will need their report) and the possible timing for depositions and trial.
  • Clarify with your experts the rules in your jurisdiction on methods of communication. Are the experts’ work product and communications subject to discovery? 
  • Control your experts. Remind them that they are not advocates (an easy trap to fall into, and the number one concern of many trial judges). Define very carefully their roles and responsibilities, and the limits to those. And remember that if your experts’ work is thrown out on a motion in limine, you have wasted a lot of time and money. (I have seen it happen.)
  • Be sure to review drafts of your experts’ reports. If there is no discovery issue, then it is a simple matter to email drafts back and forth; in jurisdictions where there is discovery of experts’ communications, there are other ways to maintain confidentiality, such as the use of screen sharing on a Zoom call.
  • • Rehearse before the deposition and especially before trial. Your experts’ report will be the basis for their deposition, which will be the basis for trial testimony, so it is important for the experts to be consistent. That underscores the importance of a rehearsal, perhaps even a ‘mock deposition’ that includes the role-playing of difficult questions.
  • Use the experts to assist in preparing detailed trial exhibits.
  • If your case gets to a jury trial, help your experts appreciate that their role has shifted from “expert” to “educator,” serving to clarify complex issues to a jury that may be feeling overwhelmed by the last stages of the trial. Make sure your experts understand the need to demystify and explain the case.

Your experts should be an integral part of your legal team, capable of adding considerable value to the ultimate resolution of your client’s case, if you manage them well. 

Dr. R. Don Keysser, CM&AA, is the managing principal of Hannover Consulting. He has been an investment banker and business finance consultant for over 40 years, and has testified on financial matters in 49 civil cases to date. He is on the adjunct faculty at the Carlson School, University of Minnesota, and at Saint Mary’s University. 

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