Steven Babitsky, Esq.


Many cases rise and fall based on how your expert witness does at their deposition. Here are some of the biggest mistakes lawyers make when preparing their expert witness.

Failure to Ask the Expert Witness What They Are Concerned About

Most expert witnesses, even the most experienced ones, have issues that they are worried about coming up during their deposition. While some of these might seem inconsequential to you, the expert may be distracted by these concerns, and as a result, underperform at their deposition.

Examples of some of these issues I have encountered when preparing experts include: job firings, messy divorces, minor criminal matters, bankruptcies, social media posts, etc. I always start a deposition preparation with the question: What are you most concerned about? Getting these issues out in the open and explaining how the minor matters are inconsequential and the more serious ones can be dealt with a motion in limine permits the expert to concentrate on the real issues in the case and excel.

Not Giving the Expert Enough Preparation Time

Due to the crunch of time, other business lawyers often provide the expert with limited preparation time. Meeting with your expert witness in person or on the phone for 30 minutes is rarely adequate to properly prepare your expert witness for their deposition. The question of how long is sufficient is easily answered: as long as necessary so both the expert and you are comfortable with their ability to answer the questions they are likely to be asked. It is good practice to do the preparation at least a few days before the deposition and not at the last minute.

Failure to do a Practice Deposition of Your Expert Witness

The saying we have at SEAK is that “you can’t learn how to ride a bicycle by talking about it.” This means that you need to actually practice riding the bike to learn how to do it. This same principle applies to deposition preparation (e.g. you need to practice it).

During our preparation session, I do a complete practice deposition with the expert. Asking the expert the most difficult and vexing questions during this practice session exposes the expert to these questions and permits them to think through their answers in advance of their deposition. The last thing you want is your expert to be asked a question they have never heard before and have no idea how to answer. When the expert tells you after their deposition that your practice session was more difficult than the actual deposition, you know you did your job well.

Explaining the Goals of Counsel in the Case at Hand

After you go through the general strategies and goals of counsel at depositions, you will want to hone in on the key issues in the case at hand. The question I ask myself and the expert is: What will counsel try to get you to say? The report of the opposing expert is often a good place to start. Working through with the expert on how to deal with these issues and questions is always fruitful.

What Are Their Opinions?

Expert witnesses need, often with your assistance, to be able to explain in an articulate direct fashion what their opinions are. Counsel should not assume that your expert witness can do so without practice and preparation.


With the proliferation of successful Daubert challenges, working with your expert so they can fully explain their methodology at deposition is crucial. I have seen too many experts, even experienced ones, who cannot effectively explain their methodology and how they reached their opinions. Working with your expert can make the difference of either avoiding a Daubert challenge or being able to defeat one if it is filed.


The above are just a few of the mistakes we as trial lawyers make when preparing our expert witnesses for their deposition.

If you would like additional information on this topic, contact me for a complimentary copy of our 359-page book, How to Prepare Your Expert Witness for Deposition.

About the Author

Steven Babitsky, Esq. is the President of SEAK, Inc., The Expert Witness Training Company ( He can be reached at or 508-548-9443.