Blog Post

Preparing Your Expert Witness

Written by: Jennifer de la Chevotiere & the Expert Depos Legal Team

Last month, we talked about why getting access to depositions is so important. If you missed it, you can catch up here.

This month, we’re back on the topic, discussing the concrete tactics you can use to ensure your expert witness is well prepared to give a rock solid deposition.

Before we get started, please note that this article is for reference only and should not be taken as legal advice.

When preparing a lay witness, it’s clear that they will need a lot of preparation going into a deposition. But, when it comes to expert witnesses, who are smart, professional, and have maybe given several depositions in the past, there is a tendency to assume that preparation isn’t necessary.

It’s important to remember that although they are an expert in their field, your witness is likely not a legal expert, no matter how many depositions they have given in the past. When communication is not clear, it leaves room for misinterpretation of your expectations, which may be very different for your case than it was for lawyers they have worked with in the past.

Your witness’ job is to tell the truth as they see it, but your job is to ensure that they can convey and defend their opinions clearly, without being pushed off track by the opposing counsel or committing substantive errors.

What Your Witness Needs to Know

Most lawyers understand that going into a deposition, your witness should have a good understanding of the extent and types of questions that will be asked, the probable length of the session, and the time and location.

But sometimes, the finer details are forgotten or deemed unimportant. But even the little things can make a difference.

Let your witness know everything that could disrupt the session, such as where to park, where to sit, how to dress, the demeanor they should convey, and whether they will be videotaped. In the case of a taped session, the witness should be particularly prepared for how their tone and facial expressions could be interpreted.

Ask your witness if they understand pertinent legal terms, and let them know that it’s ok to say that they don’t understand a question, to ask for clarification, or to not answer questions that are purposely confusing or loaded.

Confusing Questions should be rephrased, so remind your witness that they should not try to interpret what is meant and continue to answer. Rather, they should ask for clarification and remain silent until the question has been reworded.

Your witness should understand that they are only expected to answer the direct questions asked, and that if they freely offer additional information, it could open a line of questioning that is not advantageous. Similarly, you should know what is contained in the expert’s report, and advise them to stick to the information in that report as closely as possible.

Finally, discuss the types of deposition tactics that could be used to trip your witness up. These include wearing them down, getting into a rhythm, Daubert set up, repetitive questioning, and pushing buttons.

Make it Easier

To ensure that your witness is in peak form to give a deposition, pick a time where you know they will feel fresh and clear-headed. Also, make sure they are given enough time to review the necessary details and feel as prepared as possible.

The little things can make a difference. Try to pick a location where your expert will be comfortable, with proper ventilation, a reasonable temperature, and lighting that is not too harsh.

If possible, have water and refreshments available to keep your witness fueled through a long session.

If your witness wants to control the location, warn them of the risks of conducting the deposition in their own office. A personal office tends to feel more informal, which is not the attitude a witness should have entering a deposition. They will also have access to records that should not be consulted during the session, and may be more prone to distraction in a familiar place.

Review the case

To be fully prepared, your witness will need to be briefed on all relevant details of the case. They should know the date of the incident in question, the dates key tests were performed, when records were retrieved and by who, and when they were first contacted to participate.

Put together a set of all the relevant materials, and organize them with a logical flow of information from topic to topic. Ensure that you personally touch and review every document in the file.

As your witness prepares their expert’s report, ask that they keep track of any revisions and notes as they go.

Before going into the deposition, ask your expert witness if they have any questions about the case that need to be clarified.

Know Your Witness

For a smooth deposition, it is vital to gather all the information you can about your expert witness. First, you should review their education and CV to ensure they have the right professional background. Then, research their standing in their professional community their credentials will not be questioned. Ensure there is nothing in their professional past that could ruin their credibility (malpractice, citations, review board complaints, etc.).

Next, look for past depositions they have given, if they exist. This will give you a good idea of how they tend to answer questions and will help you find and documented instances of testimony that conflicts with the opinion they are prepared to give for your case.

At this time, it would also be helpful to collect past depositions of the opposing counsel to better understand their questioning style. This will help you paint a picture of likely scenarios for your witness.

For further insight into your witness, attempt to contact the attorneys they have worked with in the past. Other attorneys may be able to warn you about potential issues with your witness that are not evident in the available documentation. These issues may include poor active listening skills, rambling, or a tendency to interrupt.

Seek to understand how your witness words their opinions, and help them understand how to word things in a way that does not leave it open to interpretation.

Throughout the process, you should ask your witness if they remember anything of importance that they forgot to mention during previous meetings. It is hard to say when a witness may remember a paper, article, or other document where they wrote or otherwise conveyed an opinion that conflicts with current testimony.

Finally, remember that jurors will find it difficult to connect with a witness they dislike. No matter how impressive their credentials are, witnesses who are rude, arrogant, impatient, convoluted, unmindful of courtroom decorum, or who dress unprofessionally could pose a credibility problem. If there is any chance of the case going to court, ensure that your witness is personable and understandable.

Practice Makes Perfect

Take time before the deposition to practice likely questions with your witness. This will let you evaluate their response style and determine if there are any issues that need to be resolved before the deposition.

Review common questions that are designed to trick them or be intentionally difficult to answer.

These questions include: When did you first form your opinion? Is your opinion subjective? Have you done everything necessary to give me your full and final opinions? Is opposing expert a recognized expert in your field? Are you nervous? Do you keep current with the literature in your field? Is your CV current, accurate, and complete?

They will also need to be aware of potentially awkward money questions such as: What is your hourly rate? How much have you been billed to date? How much are you owed on the case to date? What percentage of your income that comes from legal matters? What percentage of your work is plaintiff versus defense? How often have you testified? In which jurisdictions? For which sides?

Offer your witness a list of difficult general questions like those above, as well as a list of 10 to 20 case-specific questions that they should be ready to answer truthfully and accurately.

To help prepare your witness to answer difficult questions, video record practice sessions. This will allow you and your witness to see how they come across, making it easier to make adjustments.

Finally, let them know they should be ready to answer any autobiographical questions, especially a detailed account of anything listed on their CV.


We hope this helps you better prepare your expert witness heading into your next depositions.

If we’ve missed anything that helps you, or you’d like to chat about these recommendations, please let us know.

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You can tweet us @expertdepos and/or use the hashtag #expertdepostech

Posted by ExpertDepos  March 12, 2018  3:34 pm