Expert Deposition Testimony and Responding to the Motion to Exclude Your Testimony Reviewed by Momizat on . What You Say and How You Say it Matters (Part VI of VII) Anticipate that opposing counsel will challenge some aspect of the report and suggest flaws notwithstan What You Say and How You Say it Matters (Part VI of VII) Anticipate that opposing counsel will challenge some aspect of the report and suggest flaws notwithstan Rating: 0
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Expert Deposition Testimony and Responding to the Motion to Exclude Your Testimony

What You Say and How You Say it Matters (Part VI of VII)

Anticipate that opposing counsel will challenge some aspect of the report and suggest flaws notwithstanding the hard work. How you present yourself and testify is of utmost importance. In this article, the author shares her views on how to prepare and address the criticism that will be leveled at you and your report.

expert-testimony-motionAfter many attorney communications, and hours of writing, editing, and refining, your expert report has been filed.  You are proud of your work product and are ready to take a break.  Not so fast!  Your deposition is coming up and you will need to be ready.  The expert deposition is one of the most important milestones in the discovery process because it gives the opposing side an opportunity to evaluate the strengths and weaknesses of your testimony and the case in the general.  You may not realize it, but your deposition can and probably will influence the outcome of the case before it ever goes to trial.

[su_pullquote align=”right”]Resources:

Anticipating Daubert Challenges

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What You Say and How You Say it Matters

Attorneys have different styles when taking depositions: the aggressive attorney with a confrontational demeanor always trying to keep you on edge, the conversational attorney with a personable demeanor that wants you to keep on talking and talking, and the attorney that bounces back and forth.  Regardless of which approach they use, their goals are the same—to explore your qualifications, methodology, and opinions to learn how strong of an expert you are (or are not) and to expose any deficiencies (if there are any) in your work.  Also, when opposing counsel asks you questions, he or she is watching and listening to your responses to gauge how likeable you will be to a jury, how you handle yourself under fire, how persuasive your testimony is, and how strongly you can defend your opinions.

After reviewing your deposition transcript or watching your videotaped deposition, the opposing side may concede your side’s view of the case is stronger than theirs and propose settlement; or the opposing side may determine it has plenty of ammunition to file motions both to exclude your testimony and/or to dismiss the case.  Obviously, your deposition cannot be taken lightly, but there is no need to dread it if you are sufficiently prepared and knowledgeable on what to expect—especially from a Daubert perspective.

Prior to your deposition, opposing counsel and its retained expert(s) will have reviewed your expert report attempting to identify any flaws, and will prepare deposition questions on those topics to challenge in a motion to exclude your testimony.  Therefore, it is extremely important that you carefully review your expert report and all of the information you considered or relied upon in forming your opinions.  If you cited several publications and only used a section or two from each, be familiar with the entire articles to know if there is anything written that is contradictory to your work.  You can be sure the opposing side will find those statements and ask you about them.

It is also important that you are well versed in your methodology—what you did, why you did it, and how it fits with the issues in the case—because the attorney may frame questions about your methodology around the Daubert factors.  For example, you may be asked what the error rate is, or could you calculate an error rate; has your methodology been published, or would you publish it; what are the authorities in your field; and does your method have acceptance within that community?

If you discounted any facts or data, or chose to use a particular method over an alternative, be prepared to testify to the same explanation provided in your report.  However, if you did not include a reason in your report, then practice articulating an explanation that is clear and concise.  If your answers to questions about your data or method selection implies that you “cherry-picked” only the data or method that supported your opinion and ignored information that was contrary, opposing counsel will use your admissions to show an “analytical gap” problem and argue your methodology is unreliable in a motion to exclude your testimony under FRE 702 or similar state rule.

Also, upon reviewing your report, if you find any mistakes in your work, whether big or small, alert your attorney to strategize on how to handle any errors during your deposition.  Keep in mind, the opposing attorney is looking to capitalize on any mistakes you made and will use your testimony at deposition to support a Daubert challenge.

Even if you are highly qualified to testify on the subject areas in your report, expect questions about your expertise anyway.  Attorneys sometimes use the tactic of rapid-fire questions on areas that you might not be qualified in or on topics you might not know about to elicit a series of “no” answers from you.  Do not get caught up in the fast pace.  Pause to think about what your answer will mean.  You do not want to limit your expertise such that suddenly an area of inquiry in your expert report falls outside of your qualifications.  The opposing side is looking for sound bites to use in a Daubert challenge and your own testimony is the strongest evidence.

Practice, practice, practice!  Go over points of concern and run through mock deposition questions with the attorney or someone knowledgeable in your field or on the case.  Also, ask the attorney for information on what the deposing attorney’s style and demeanor is so you can prepare in advance on how to answer questions.

Responding to the Motion to Exclude Your Testimony

The motion to exclude your expert testimony has arrived.  Take a deep breath, and read the document.  You may feel the need to shake your fists, yell real loud, or stamp your feet.  It is not unusual to be angry upon reading a harsh critique of your hard work and your professional experience.  When your anger subsides, review the motion again, this time taking notes on important points you feel need to be addressed in the legal team’s response or in your affidavit.

The motion to exclude is written in such a way to explain to the court that you are not qualified and/or that your expert testimony is not reliable or relevant.  The opposing side will establish the legal basis for challenging your expert testimony by citing FRE 702, Daubert, and perhaps Joiner and Kumho, if the case is in federal court, or the relevant state “rules of evidence” and precedent-setting case on admissibility of expert testimony if the case is in state court.  The motion will then have a background section presenting the case issues and underlying areas on which you are testifying.  This section is to educate the court on what the case is about from their point of view.  The third part of the motion is the most significant—it presents the challenges to your opinion citing excerpts from your expert report, testimony from your deposition, and case law where the court excluded expert testimony where similar issues were in dispute.

As discussed earlier, during your deposition, the opposing attorney will have spent a lot of time questioning you about your professional history seeking possible deficiencies or discrepancies with your resume to establish you are unqualified to render some or all of your opinions.  The motion to exclude also may challenge your lack of real world and non-litigation experiences if your primary work experience is in an academic or laboratory setting.  Similarly, the motion may challenge your lack of scientific knowledge if your specialized knowledge was obtained through on-the-job training.  Each argument will cite case law in which an expert was excluded for lacking the requisite qualifications to render his or her opinions.  The opposing side will also attempt to challenge your credibility by citing any cases in which your testimony was excluded, even if those cases are not relevant to your opinions in this case.

Typically, the challenge to your opinions due to any methodological flaws will comprise the bulk of the motion.  The opposing side may argue that you did not have sufficient references to justify the use of your methods, or attempt to establish that a better, more appropriate methodology was available, like the one used by their expert.  They may also attempt to show that your assumptions, inputs or selection of data were flawed, insufficient, or subjective.  For example, if you excluded data or facts and did not provide a sufficient explanation in your expert report or during your deposition, the motion will argue your opinions are subjective and therefore, unreliable under FRE702(c) and not helpful to the jury.  If you are relying on data or information that you personally collected, the motion will assuredly contain arguments that your procedures were improperly conducted under conditions that did not mirror the “real situation.”

Striking Back

The legal team takes the lead responding to the motion to exclude your testimony.  They are responsible for rebutting the legal arguments.  They review the body of case law cited in the motion and argue that the judge should not abide by those court decisions because the facts and circumstances are dissimilar from the present case.  They will then cite case law that is favorable to the case and to your expert opinions, and argue that the judge should rely on that case law instead.

Your responsibility is to rebut each and every claim in the motion to exclude your opinions.  Start by reviewing your expert report and deposition testimony to locate what excerpts or soundbites the motion used—maybe they were taken out of context, snipped to cut off your full answer or a misinterpretation of what was stated in your report.  Next, communicate your points to the legal team so they can strategize with you on their response.  They will decide whether you should prepare a detailed affidavit that will be attached to their response, or included directly in their response.  Also, if you were qualified to testify in cases involving similar issues, make sure the legal team is aware of those cases.  Provide the attorney with any written decisions by the courts denying motions to exclude to your testimony if they are in your possession.

The Hearing

A hearing or “mini-trial of the experts” will be held either with or without the experts testifying.  The judge has the authority to conduct a hearing with only the attorneys for both sides arguing the motions and responses, or the judge can request that certain experts appear in court for the hearing, which is essentially another cross examination.

If you are called upon to testify, you must be totally prepared to address all aspects of your opinions challenged in the motion to exclude.  The opposing attorneys have read in scrupulous detail your rebuttal and will decide which opinions to argue in court, and may also find different avenues of attack.  Also, be knowledgeable of the opposing expert’s opinions.  You may need to show where there is agreement, and where there is disagreement between your work and the opposing expert’s methodology, and why your testimony should be admitted despite conflicting opinions.  There are always unexpected questions that you will have to handle on the spot, including questions directly from the judge.  The retaining attorney will also have an opportunity to ask you questions.  He or she may want you to clarify your earlier responses or give you another chance to explain how you are sufficiently qualified, and explain that your methodology is both reliable and relevant.

If you are not testifying at the hearing, then you are relying on the legal team to fight on your behalf.  It is up to them to clearly and concisely rebut the challenges to your testimony to the judge.  Therefore, it is critical that the attorneys fully understand your methodology—what you did, why you did it that way, and how it is applicable to the case—and fully understand how you formed your opinions based on that work.  Without your testimony, the next best thing is your affidavit, which addresses the important points you want the judge to understand.

The judge will make a decision based on your ability to convey in clear and concise language your methodology and your opinions, and why both are valid.  In general, judges are predisposed to accept expert opinions unless there are unexplained red flags that allow the other side to provide convincing arguments to the contrary.  Judges may use Daubert and the other precedent to assist in their decision on admissibility; most importantly, they need to demonstrate they reached their conclusion using sound, reasonable, and legal decision-making skills in order to pass an abuse of discretion review if the decision is appealed.  The attorney has the right to appeal the judge’s opinion; however, the bar is set high for the appeals court to overturn a judge’s decision to exclude.  The “abuse of discretion” standard means that a judge can make errors in judgment as long as the errors do not exceed the “abuse” threshold.  Judges are human and do make mistakes.  You can be excluded for what you and the attorney consider illogical reasons.  Just like in baseball, you are going to have a called third strike that is outside the strike zone every now and then.


Your deposition is an extremely important part of the discovery process because your testimony can influence the strategy of the case moving forward.  Even if you have a very strong expert report, if your testimony exposes any weaknesses in your qualifications, methodology, or conclusions, you can bet opposing counsel will use your testimony in support of a motion to exclude you.  By knowing that the opposing attorney’s deposition questions are intended to help frame a challenge to your testimony, you can prepare in advance how to answer questions about your work without providing sound bites limiting your qualifications or weakening the reliability of your methodology and opinions.

There is nothing more critical than successfully defeating a motion to exclude your testimony and being able to testify in court as to your opinions.  In civil proceedings, most cases settle prior to trial.  In essence, the Daubert hearing can be the deciding milestone for both sides.  Experts have a unique status in litigation as being able to explain in detail their versions of the case issues.  That is why the motion to exclude and the response are so important, vigorous, and challenging.  Your reputation is at stake.

This article originally appeared on in the Expert Library on May 20, 2015.

Wendy Pearson, founder of Pearson Research Group, has more than 15 years of experience providing strategic litigation support and expert witness support on over 50 major cases involving contaminants in the environment. She assists attorneys with case assessments, case strategy, understanding technical issues, fact and expert witness discovery, Daubert motions and responses, and direct and cross exams of experts at trial. Ms. Pearson fully supports expert witnesses throughout the litigation process to ensure high quality work product and sufficient preparation for deposition and trial. She holds a B.S. in Civil Engineering and a M.S. in Environmental Science and Engineering.

Ms. Pearson can be reached at (814) 240-2418 or by e-mail to

The National Association of Certified Valuators and Analysts (NACVA) supports the users of business and intangible asset valuation services and financial forensic services, including damages determinations of all kinds and fraud detection and prevention, by training and certifying financial professionals in these disciplines.

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