Bloomberg Law
April 10, 2019, 8:01 AM

INSIGHT: What Makes a Great Expert Witness? Look for the Four C’s

David  Solomon
David Solomon

Ask a dozen lawyers what makes a dream expert witness, and you’ll get 12 different answers.

Some dislike using first-time experts without testifying experience; others prefer the lack of a record to attack. Many avoid academics (fearing an “Ivory Tower” problem); others prefer the professorial approach to “teaching” a finder of fact about a difficult subject.

Virtually all litigators agree that experts must be credible and knowledgeable in their area of specialty—and that a great expert is an essential element to obtaining a favorable resolution in complex litigation.

But beyond the obvious, there’s little consensus on what constitutes a must-have. That’s a challenge for attorneys because experts have never been more important than today, as more disputes than ever now rely on understanding complicated subjects—such as the nuance of an intricate financial transaction or how a particular technology is distinct from another.

In a litigation environment where picking the right expert is more important than ever—and a miss can mean catastrophe—how does a litigator identify the must-have traits in an expert? And how can lawyers test potential experts for these characteristics, especially during limited preliminary conversations?

A good place to start is with the “Four C’s”:

Clear Communicator

As experienced as an expert may be, he or she must be able to transfer deep subject matter knowledge from his or her mind to that of the finder of fact. Knowing the inner workings of an intricate subject does not always mean one can explain it equally well to the uninitiated or lay.

As technical specialties become more and more complex, selecting a clear and concise communicator becomes more and more important. The best experts can speak technically yet eloquently, not only to industry peers but to someone who has no basis of knowledge in the subject matter.

Test for it: Ask the proposed expert to explain a topic in his or her wheelhouse to you and your litigation team in a time-banded interval—preferably on a subject about which you and your team are not well-versed. Ask follow-up questions. How did the expert do explaining something complex in a narrative format to the uninitiated? Was he or she able to clarify areas of opacity via their answers to questions?


Experts, by definition, are often the smartest people in the room, and they’re frequently in a position of authority over how things around them are conducted.

But litigation is a team sport. Experts who work well with others, in a matrixed environment and under pressure, are a godsend to a litigation team; an expert that sees him or herself as the sun around which the rest of the case orbits can quickly become an obstacle to be carefully negotiated, or worse, a potential liability.

Whether experts have testified hundreds of times or never, a litigator will almost certainly need to give them feedback and counsel about how to come across most effectively and prepare thoroughly. The expert worth her salt embraces working on a team and incorporating constructive suggestions to maximize performance and impact.

Test for it: Ask experts how they like to receive constructive feedback and for an example of a circumstance in which receiving it aided in their job performance. Professionals that operate well in a team environment and are open to and inviting of feedback will have specific examples of how this has made them better, whether in a litigation context or otherwise.


While experts might have mastered a particular subject matter, their confident (but not overly so) delivery of the information is paramount. Though one may expect that a confident manner goes hand-in-hand with clear communication, that’s not always the case.

Sometimes a clear communicator may come across as knowledgeable but not particularly confident—or, just as problematically, excessively so.

The finder of fact must not only find experts to be credible, but also feel that—in an adversarial proceeding, where another well-credentialed expert will be refuting many points they make—experts come across as having mastery of the subject while believing in both their conclusions and themselves.

Test for it: In many ways, confidence is subject to the Potter Stewart test—you know it when you see it. That said, asking for an anecdote from the expert’s professional experience where he or she had to overcome a difficult obstacle, situation, or impediment can give a glimpse into the confidence level and resilience of the expert.


Last, but certainly not least, candor and transparency are underrated as character traits of a successful expert.

Good experts can tell you what they know and advocate forcefully for a position. A great expert will be clear on not only what he or she knows but also assess the relative merits of a position, opinion, or view in a fair and balanced manner.

Test for it: Ask experts about a time that they had to deliver unfavorable results or a bad outcome in their career. How did they prepare for the conversation? What was the approach? How comfortable were they in providing candor and transparency to an audience that wanted different news?

Choosing an expert is both art and science, and every litigator, case, and client is different. In the end, the most important thing is selecting the expert you and your client trust to advocate your position. Hopefully, the Four C’s will help you arrive at that conclusion more reliably.

This column does not necessarily reflect the opinion of The Bureau of National Affairs, Inc. or its owners.

Author Information

David Solomon is Global General Manager with GLG Law, a platform that connects lawyers with expert witnesses in complex fields. He was previously with Axiom Global and Bloomberg LLP.

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