In modern litigation, there are very few tasks that are as satisfying -- and potentially as impactful -- as winning the expert witness battle. While some wins are definitive and achieved in a blaze of expert-exclusion glory, most are accomplished through careful planning, methodical attention to detail, and, most importantly, an approach that assumes, however unlikely, that you will be cross-examining the opposing expert at trial. In other words, a winning strategy is generally one that prepares your case for the long-game, from the beginning. Below, we have outlined the five key steps to dethroning the other side's expert. Don't let time, or costs, completely dictate your strategy. Although not every task in each step is necessary and appropriate in every case, your thoughtful consideration of each step, and the pros and cons of each task, is. Good luck and, in the words of Suzanne Collins, may the odds be ever in your favor.
1. Do your homework. When it comes to countering an opponent's experts, there is no such thing as too much preparation. It does not matter what kind of case you have or how much experience in the subject matter you have to begin with, to prepare your case for trial you will ultimately need to know who the opposing experts are, what they plan to say, and how to best dismantle or limit the impact of their testimony.
For the most part, the first step for everyone is to learn the subject matter. Indeed, your ability to understand and speak the language will be critical to your success in the remainder of the tasks. This does not mean that you need to become a rocket scientist if your case is about rocket fuel. It does mean, however, that -- at a minimum -- you need to know what a rocket is, how rockets work, what rocket fuel is made of, who the leading rocket-fuel manufacturers are, and who the leading rocket-fuel experts are, including whether such expertise is further narrowed (for example, is there only one type of rocket-fuel?).
For some types of cases, especially those involving highly technical issues, you may need to engage your own expert, or a consultant, early in the case to help you achieve the desired level of understanding. In California, "consulting" experts who are hired solely to help you evaluate your case (and who will not testify) are generally not discoverable. See Williamson v. Superior Court (Shell Oil Co.), 21 Cal. 3d 829, 834 (1978). However, be careful: If you later end up needing to designate the consultant as a testifying expert, your opponent is entitled to discover all reports prepared by him/her -- including those that were generated as a "consultant" and would have been otherwise subject to "work product" protection. See, e.g., Shadow Traffic Network v. Superior Court (Metro Traffic Control, Inc.), 24 Cal. App. 4th 1067, 1079 (1994) ("[R]eports prepared by an expert as a consultant are protected until the expert is designated as a witness.  Then, the opponent may seek disclosure of the reports upon a showing of good cause.")(internal citation omitted).
2. Conduct purpose-driven discovery. In California, expert discovery is governed by Code of Civil Procedure Section 2034.010 et seq., which is initiated by a demand for the exchange of expert witness information. Unlike federal court practice, unless and until a demand is made, neither side is obligated to disclose their testifying experts before trial. Once a demand is made by any party, however, all parties are obligated to exchange information -- including the party that issued the demand. CCP Section 2034.260(a). Practically speaking, this means that you should affirmatively consider and evaluate the pros and cons of having your expert disclosed before trial versus discovering the other side's experts before such a disclosure would be required. In many cases, the high costs of expert discovery -- as well as the likelihood of a settlement -- are key considerations.
If you decide to make a demand, or receive one, it should ask for the names and qualifications of all experts who may be designated to testify at trial, the substance of their expected testimony, and copies of "all discoverable reports and writings." CCP Section 2034.210(c). Be mindful; the demand is subject to a number of strict procedural rules, including timing and content requirements. Whether you are preparing to issue a demand -- or respond to one -- review the rules carefully to make sure that you are in full compliance.
Once you know the identity of your opponent's expert(s), begin preparing for their deposition(s) immediately. You may only have a narrow window of time to conduct the deposition, so much of your subject-area research should have already been done before the expert exchange date. Do not rely on only the information provided in the expert disclosure. Investigate the expert's resume to the greatest extent possible. Is it truthful? Are you able to verify the expert's education credentials and experience? Google him/her. What have others in their field said about them? In particular, investigate the expert's writings and prior opinions -- look for inconsistencies. Use your own expert, or consultant, to review their resume, credentials, and report (if produced).
In conducting the deposition, your goal is to discover each and every opinion that the expert intends to give -- and the basis thereof. Although tempting, do not waste time -- or unnecessarily tip your hand -- by arguing with the witness, using your best impeachment evidence, or completely outlining your challenges to his/her opinions. Stay focused. Draw the expert's opinions out and box him/her in. After the deposition, line up the deposition pages and video for impeachment at trial so that such excerpts are easily retrievable.
3. Develop a theory. At some point during your research of the subject matter and discovery of the opponent's expert, you should begin to develop a theory about their credentials and opinion(s). This theory will form the basis of your challenges moving forward, and may inform your overall trial or summary judgment strategy. For example, is the expert simply wrong, biased or did he/she fail to do their homework? Does the expert always testify for the same side? Are the expert's key assumptions flawed? Did the expert follow the established protocol in the relevant field?
Some examples of using cross-examination to establish a theme are discussed in Step 5 below, which demonstrates the use of precise questioning to show either that an expert did not follow established protocol or is not adequately educated in the area of purported expertise.
4. Use motions in limine to limit areas of expert testimony. In addition to the other pre-trial preparation, motions in limine can be effective in setting the parameters for an expert's opinions. This is especially important as to unqualified experts, who will sometimes try to use the soap box of the witness stand in an effort to espouse theories involving the entire case. Exposing the fallacies of such testimony through cross-examination can be an up-hill battle. Instead, take the offensive to preclude such improper testimony.
Federal Rule of Evidence 702 provides that an expert "qualified ... by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise if:
"(a) 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;
"(b) the testimony is based on sufficient facts or data;
"(c) the testimony is the product of reliable principles and methods; and
"(d) the expert has reliably applied the principles and methods to the facts of the case."
California Evidence Code Section 801 contains a similar restriction. These provisions can be used in supporting pretrial motions in limine designed to restrict an expert to opinions that are actually within that person's field of expertise and/or limit opinions based on unreliable methods or data. Such motions, commonly referred to in federal practice as a "Daubert motion," based on the 1993 Supreme Court case, Daubert v. Merrell Dow Pharms., 509 U.S. 579, have a robust body of case law that you can pull from. Do your research; the specific issue may have already been addressed by the courts. Critically, if such a motion is successful, the areas of direct and cross-examination can be limited, potentially even excluding the expert entirely, and counsel can avoid the task of discrediting opinions through cross that should have never been permitted.
5. Plan for and conduct a strategic cross-examination. Cross-examination is a prime example of the principle that less can be more. A lawyer's natural inclination may be to question the expert on the many topics that are elicited on direct. One may assume that it is necessary to do this in order to neutralize the most damaging aspects of the expert's testimony. However, in many cases, the results of such a strategy could be fruitless because such questions will simply provide the expert with another opportunity to reiterate those damaging opinions. When given an opportunity, an experienced expert will welcome the opportunity to expound on the opinions, often offering further examples and more support for the initial testimony.
Instead, a more fruitful strategy when cross-examining an experienced and knowledgeable expert is to identify focused areas that are likely to elicit helpful admissions from the expert. For example, counsel may know from the expert's deposition that the expert did not run certain tests that could have been helpful, or that the expert accepted certain facts as true and based opinions thereon, or that the expert did not review all of the documents provided by the opposing party. When one is sure from the expert's report or deposition testimony that such things were not done, precise leading questions can be used to elicit these admissions so that the expert has no choice but to agree. Once these limited admissions are established, you may wish to go no further and risk providing the expert with an opportunity to rehabilitate prior testimony.
The following is an excerpt of cross-examination during the O.J. Simpson murder trial which demonstrates the impact of a focused and limited area of cross-examination. Criminalist Dennis Fung was questioned by defense attorney Barry Scheck concerning the proper storage of blood samples taken from a crime scene prior to DNA testing. In this exchange, Mr. Fung unsuccessfully tries to defend his decision to store blood samples in plastic bags. Scheck uses very focused questions to challenge Mr. Fung's techniques as not in compliance with accepted protocols:
Q: DO YOU RECALL, IN THE EDITION OF FISHER THAT YOU READ, WHETHER MR. FISHER INDICATES THAT: "IT IS A CERTAINTY THAT WET OR DAMP BLOOD STAINS PACKAGED IN AIRTIGHT CONTAINERS SUCH AS PLASTIC BAGS WILL BE USELESS AS EVIDENCE IN A MATTER OF DAYS"?
A: I DON'T RECALL THAT, BUT THAT IS WHAT IT SAYS IN THIS BOOK.
Q: AND THAT: "ANY TYPE OF PRESERVATION TECHNIQUE THAT HASTENS PUTREFACTION SHOULD BE AVOIDED"?
Q: PUTREFACTION WOULD BE DEGRADATION?
Q: THUS STORING BLOOD STAINS THAT ARE STILL DAMP IN AIRTIGHT CONTAINERS OR IN WARM ENVIRONMENTS WILL ACCELERATE DETERIORATION OF THE SPECIMEN?
A: THAT'S CORRECT.
Q: CONVERSELY, AN AIR DRIED SAMPLE STORED IN A PAPER BAG AT ROOM TEMPERATURE, OR BETTER, UNDER REFRIGERATION, WILL RETAIN ITS EVIDENTIARY USEFULNESS ... ?
A: THAT'S CORRECT.
Q: DO YOU AGREE WITH MR. FISHER?
A: MR. FISHER IS REFERRING TO FINAL PACKAGING ... AND I DO AGREE WITH THAT.
Q: WHERE IN THIS PASSAGE DO YOU SEE ANY REFERENCE TO MR. FISHER SAYING THAT HIS ADMONITION AGAINST USING PLASTIC OR AIRTIGHT CONTAINERS ONLY APPLIES FOR FINAL PACKAGING?
A: WELL, IN THIS ONE PHRASE HERE IT SAYS, "WILL BE USELESS AS EVIDENCE IN A MATTER OF DAYS," THAT TO ME MEANS THAT THAT WOULD BE FINAL PACKAGING.
This exchange demonstrates how a focused cross-examination directed to areas where admissions are probable is likely to have the greatest impact. The cross-examining attorney should then know when to stop after asking these pointed and leading questions. An effective cross-examination can be ruined by asking even one too many questions that provide the expert with an opening to disavow the earlier and very damaging admissions.
Another potentially successful technique is to explore areas that are unknown to the expert. The following is an excerpt from the cross examination of an expert witness engineer in a famous murder case in the U.K. The defendant was on trial for murdering a passenger in a car by setting fire to it. The defense argued that it was an accident and called an expert witness who testified on direct that the fire was caused by a mechanical defect. On cross-examination, the prosecutor began by persistently asking about a principle that was not known to the expert:
Q.: WHAT IS THE COEFFICIENT OF THE EXPANSION OF BRASS?
A: I BEG YOUR PARDON?
Q: DID YOU NOT UNDERSTAND THE QUESTION?
A: I DID NOT HEAR YOU
Q: WHAT IS THE COEFFICIENT OF EXPANSION OF BRASS?
A: I AM AFRAID I CANNOT ANSWER THAT QUESTION.
Q: IF YOU DO NOT KNOW, SAY SO. WHAT IS THE CO-EFFICIENT OF EXPANSION OF BRASS?
A: YOU WANT TO KNOW WHAT IS THE EXPANSION OF THE METAL UNDER HEAT?
Q: I ASKED YOU: WHAT IS THE COEFFICIENT OF THE EXPANSION OF BRASS? DO YOU KNOW WHAT IT MEANS?
A: PUT IT THAT WAY, PROBABLY I DO NOT
In the above example, the expert had to admit that he was not familiar with the area of inquiry -- which undermined his credibility on issues relevant to the case. The cross-examiner was pointed and persistent. The result was that an easy to understand admission was elicited that the attorneys can later use to argue that the expert's opinion should be discredited.
Countering an opponent's expert, whether in cross-examination or pretrial motion practice, can be one of the most difficult aspects of trial practice. With some heavy preparation and a strategy that plans for the long-game, however, this can be a productive and winning part of your case. While not addressed in this article, equal preparation should be devoted to your own experts so that they may avoid the pitfalls discussed above.