Successful Daubert Motions: Best Practices for Challenging an Opponent’s Expert


Daubert ChallengeExecuting a Daubert challenge against an opposing party can be the deciding factor in whether you win or lose a case. Due to the enormous consequences a Daubert challenge can have, it is important for any practicing trial attorney to understand how to execute a Daubert challenge, when to do so, and strategies relating to the execution of such a challenge. Below, we’ve broken down the process of launching a successful Daubert challenge against opposing counsel’s expert to help you identify the right situation to deploy a gatekeeping challenge. As well as a step-by-step method to give your challenge the greatest chance of success.

Identify When a Daubert Challenge is Needed

Daubert hearings are not required for a determination that dictates whether expert testimony will be excluded or admitted. Any method of review is permitted so long as the court performs an evaluation with a sufficient record for appellate review, and articulates the reasons for its decision. However, Daubert challenges are important. If granted, they guarantee that the court will extensively review the admissibility requirements of Federal Rule of Evidence 702. This requires that a witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:

  1. The expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or to determine a fact in issue,
  2. The testimony is based on sufficient facts or data,
  3. The testimony is the product of reliable principles and methods,
  4. The expert has reliably applied the principles and methods to the facts of the case,
  5. Additionally, some federal courts require a Daubert challenge if any review of an expert is to be made.

Do Your Research

It’s important to thoroughly prepare before making a Daubert challenge. Beginning by researching the scientific or technical issues involved in the expert’s testimony. After this, you should perform background research on the expert witness, including:

  1. The expert’s past publications,
  2. Deposition and trial transcripts,
  3. Licenses and certifications,
  4. The record of previous Daubert challenges against them,
  5. A full background check, if possible.

After performing a comprehensive background review, you should retain your own expert in the field who can document the opponent expert’s errors through a deposition of their own. You should prepare a counter declaration with your own expert to show that the challenged expert’s methodology is unreliable. This is after your opponent’s expert makes a declaration in opposition of the Daubert challenge.

Choose Your Moment Carefully

Daubert challenges can be made in many forms, including:

  1. A separate motion,
  2. As part of summary judgment,
  3. A motion in limine,
  4. As an objection made at the time the testimony is given,
  5. In a post-trial motion.

Technically a Daubert challenge can be made at any point in the case. However, it is wise not to make a Daubert challenge too late in the trial. In 2001, 10th Circuit case (Alfred v. Caterpillar, Inc, 262 F.3rd 1083, 1087) held that a Daubert challenge raised late in trial process most likely will not be approved.

Additionally, in many cases, the trial judge will issue a scheduling order that specifically includes deadlines for challenges to the admissibility of expert testimony. If a party does not comply with the order, it will likely be found that any objections have been waived. If a party waits to object until the time the expert testimony is actually offered, the trial court will likely refuse it for this reason as well. Even if a scheduling order was absent. Therefore, it is always best to challenge before the expert testimony is admitted. Although not too early as to give the opposing party ample time to correct the deficiencies.

Do not hesitate to object to an expert pre-trial if it might help to avoid a trial altogether. If a pre-trial objection fails, the moving party does not need to reassert the challenge in order to preserve it. The movant can reassert it once the evidence is actually offered. At that time you can request a Daubert hearing if one was not previously conducted.

Consider the Scope and Content of Your Challenge

A movant can modulate the extent of the Daubert challenge as suits their case. In some cases, the challenge might simply involve a review of expert reports. While in other instances a Daubert challenge might be a lengthy proceeding involving live testimony of the expert. If you decide that you want a full Daubert proceeding, it is important to show good cause in the motion.

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As far as the content of the Daubert challenge, a movant for a Daubert challenge should focus on competence, relevance, and reliability. It is tempting to focus on the conclusions of the expert. However, judges will most likely prefer to allow any conclusions to be decided at trial. Admissibility determinations can still be outcome-determinative if the expert witness was to present the only question of fact in the trial. Because courts may be reluctant to exclude testimony when it would result in deciding the entire case, it is important for a challenging attorney to remind the court that the issue is simply one of admissibility; where the burden remains on the proponent of the evidence to prove admissibility by a preponderance of the evidence.

Account for your Judge

Another factor in determining what type of case you have is to look at the history of Daubert challenges involving the judge sitting trial. Try to determine if there is is a correlation between the judge granting or denying Daubert motions and the lengthiness of such motions. A judge will have the ultimate say on the extent of the Daubert challenge. Although you should make a request that best suits the strengths of your case.

Regardless of the request you make as to the extent of the Daubert motion, a judge may decide to have a full hearing or an expedited one depending on the point of the trial the motion is being made. If the expert witness testimony would create the only triable issue of fact, file the Daubert motion as part of summary judgment. Citing to the opponent’s expert’s deposition and your own party’s expert’s affidavits. Keep a look out for the expert witness changing his or her testimony. This is a sign that there was likely some flaw in the original testimony. Or that they are trying to bring up something that might not have survived the original objection.

Minimize the Chance of a Backfire

You should also consider whether the challenged expert might do a better job verbally explaining their qualifications or methodology than they did in their written papers. Thereby making a Daubert hearing an opportunity for opposing counsel to strengthen their position. A few important questions to ask before initiating a Daubert challenge include:

  1. Did the expert leave out certain relevant qualifications they had that they may bring up in an oral deposition?
  2. Was their methodology poorly explained but possible to correct if the expert is given a second chance?
  3. Consider if it would be beneficial for a jury to witness a full evidentiary hearing. Will the challenging attorneys and their experts present a better case for admissibility than the challenged expert witness will on the stand?

To avoid a hearing in the presence of the jury, you can file the Daubert challenge as a separate motion, or motion in limine, and not as a part of a motion for summary judgment. You can also point to a lack of contested fact issues, or simply cost considerations, in order to support a request that the court rule without a hearing.

Defending Against Daubert

How about opposing a Daubert challenge made against one’s own expert witness? It is important to remember that the proponent of the expert testimony in this case has to prove with a preponderance of evidence that the expert is qualified, and that the testimony is reliable and relevant. Therefore, it is important to keep a complete record of testimony and briefs establishing that the expert testimony is based on reliable methods and will assist the trier of fact. An attorney’s summary explaining this is not enough. The expert must put forth the evidence that his or her testimony meets those standards. This evidence can be put forth in the following ways:

  1. Via the expert’s own deposition testimony,
  2. An affidavit of the expert explaining why the methodology used is reliable,
  3. References to published articles and other academic works supporting reliability of expert testimony,
  4. Affidavits of other experts in field,
  5. Prior testimony of your opponent’s experts.

You may request extra time to provide these materials, and therefore should request sufficient time to gather all necessary materials. Regardless, a prudent attorney should position themselves to have this evidence ready on short notice in case a challenge comes up at trial and a request for more time is not granted.

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