United States: Asking The Right Questions At The Expert's Deposition To Lay The Foundation For Your Client's Daubert Challenge

Deposing your adversary's liability expert is not only a chance to delve into the details of the expert's opinions, but the deposition also presents a great opportunity for defense counsel to explore the sustainability of the expert's opinions going forward. In the context of a products liability case, the plaintiff's expert's deposition, if used wisely, can set up an effective challenge to the expert's proffered opinions under the Federal Rules and can result in the expert's eventual disqualification. Perhaps nothing is more devastating to the Plaintiff's case than the loss of his expert for all, or even part, of the case.

To review, and at the risk of oversimplification, Daubert v. Merrell Dow Pharmaceuticals (1992) and its progeny established the notion that our federal district trial courts should act as "gatekeepers" to assure that only sound expert testimony – that is, opinions that are the product of a valid scientific method – gets presented to a jury. Rule 702 requires the expert to be qualified by knowledge, skill, experience, training or education and further requires the opinions to be based upon sufficient facts and data. The expert is supposed to utilize a legitimate methodology to develop his or her theories. Thus, an examination of the purported expert's qualifications, the facts and data upon which the opinions are grounded, and the expert's methodology are ripe for a thorough examination during the expert's deposition. What follows are suggestions regarding various lines of questioning that may effectively set up your adversary's expert for the later Daubert challenge should you encounter an expert's opinion that is the product of suspect qualifications, insufficient facts and data and/or speculative methodology.

In this multi-part blog series, we'll focus first on the expert's qualifications. Let's take the case of an expert who has rendered opinions about the allegedly defective design of a power tool. Effective examination during his deposition may reveal that, in fact, the expert has never designed a power tool in his life, has never been involved professionally in the manufacturing of a power tool and, certainly, has never written any books, articles or treatises on the design of such a product. Further examination may show that the expert has never been involved in the formulation of an Operator's Manual for a power tool (including its warnings/instructions) or its warning labels. Chances are that he has never been consulted by a real-life manufacturer on quality control or testing procedures. There's even the chance, if not the likelihood, that the expert does not own a power tool and hasn't used one in many years.

Experts like to tout their membership in various professional organizations as a way to buttress their claimed qualifications. By way of careful questioning, however, I often learn that membership in many of these professional organizations comes easily. For example, many of these so-called "professional" organizations only require that you fill out a form and send in a check for the dues − "VOILA," you're a member of the "XYZ Association of Widget Engineers." Should one be impressed by mere membership in a myriad of such organizations?

Instead, in my experience I often have found that the purported expert has been an inactive member of the organization for many years and cannot even recall the last time that he or she has actually attended a meeting of the professional society. Even if active, it is often the case that the expert has never sat on any subcommittee that actually sets safety standards for any product, such as Underwriters Laboratories, the American Society for Testing and Materials and/or ANSI and has never partaken in the actual process of writing voluntary or mandatory design standards. It also is likely that the purported expert has never worked, or consulted, with the Consumer Product Safety Commission or OSHA – two government organizations with direct regulatory powers over many of the products we encounter in everyday life.

Many experts we encounter on the defense side of products liability cases, in order to showcase their purported expertise and experience, frequently mention that they have handled similar cases in the past. That may be true, but careful questioning (after some old-fashioned investigation) often will establish that the expert has been involved in, and given opinions of "defect" about, nearly every kind of product imaginable. The "A to Z" method of questioning is often used here: "Mr. Expert, you have rendered opinions before in a case involving an aerial lifts? Brake press? Crane? Drill?" – and so on. Done effectively, this kind of questioning shows the expert to be more of the "jack-of-all-trades" type with no real expertise in any particular area or discipline relevant to the case at hand.

Experts, of course, like to tout their extensive education and formal training in order to support the notion that he or she is qualified to render their opinions. Their CV will be riddled with many degrees from various educational institutions and they will undoubtedly have amassed a series of initials after their name – like Ph. D. or P.E. Closer examination during the deposition is warranted, however. In my experience, I have found experts with degrees in mechanical engineering trying to render opinions more appropriate for an electrical engineer, and vice-versa. They may have a degree in some relevant field of engineering, but not a license. Sometimes they claim expertise in accident reconstruction but, upon further questioning, concede that the claim is based on in-field experience only and not through any formalized education or instruction.

In my next article, we'll examine the next area of potential questioning to set up a successful Daubert challenge – these questions specifically targeting the "sufficient facts and data" upon which the expert's opinions are supposed to based.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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