Whether to Conduct Depositions of Expert Witnesses

In a Litigation magazine article, Gregory Joseph sets out some strong reasons to consider for not conducting depositions of expert witnesses under the revised 2010 Federal Rules of Civil Procedure (FRCP). See Gregory P. Joseph, “The Temptation to Depose Every Expert,” 40 Litigation 35 (Winter 2014) [cited below as Joseph]. Joseph points out that FRCP 26(a)(2)(B) requires parties to disclose, for all retained expert witnesses, “all opinions” and the “full factual basis” of all their opinions, among other things. The rule is exacting. All opinions includes “a complete statement of all opinions the witness will express and the basis and reasons for them.” FRCP 26(a)(2)(B)(i). And a full factual basis includes “the facts or data considered by the witness in forming” all of the opinions disclosed in the report. FRCP 26(a)(2)(B)(ii) (emphasis added).

Joseph argues that the breadth of the required disclosure, combined with sanctions for retained expert witnesses’s attempting to testify beyond the four corners of their reports, should give lawyers sufficient assurances in many instances to forego conducting depositions of expert witnesses.

Joseph notes that the FRCP creates a presumptive mandatory sanction of exclusion for undisclosed expert testimony. FRCP 37(c)(1).[1]  Joseph offers other arguments beyond the supposed comfort given by the “four corners” rule set out in the FRCP. Joseph at 36-37. First, the deposition may “reopen” discovery by giving expert witnesses opportunities to expand upon the four corners of their reports. Although some courts will limit what expert witnesses can throw over the transom at depositions, a supervising magistrate or district judge may not regard the expansion upon the disclosures in the report as “sandbagging,” and thus fail exclude the arguably new opinions or bases. Joseph cites a few cases in which courts condemned the sandbagging of counsel by the offering of new opinions in depositions, but points out that exclusion is this circumstance is highly discretionary. The court is not required to exclude, and it may permit the new material, or allow the new material with an inadequate amount of additional time in deposition. So taking the deposition has risks.

Joseph argues also that depositions may educate expert witnesses about intended trial cross-examination, and help adversary counsel better prepare direct examination and anticipatory rebuttal. Furthermore, the new protections afforded expert witnesses from discovery into drafts of reports and most communications with retaining counsel take away one of the previous reasons to conduct depositions.

To be sure, some additional areas of discovery may be covered by interrogatories, Rule 34 document requests, or Rule 45 subpoenas directly to the expert witnesses. These non-deposition methods of discovery, however, will not reach valuable topics of discovery such as oral communications between retained expert witnesses and professional colleagues, consulting expert witnesses, the retaining lawyers’ clients, and other persons. The suggested alternative discovery methods also suffer in that they will provoke canned answers, written by counsel, and not the ingenuous, unrehearsed responses of expert witnesses required to give answers directly and without resort to  “privileged” consultation with retaining counsel.

The revised FRCP carve out important areas of inquiry from the new protections against discovery into draft reports and with counsel. Counsel still are permitted to inquire into compensation, the retaining attorneys’ provision of “facts or data” considered by the witnesses, and retaining attorneys’ identification of assumptions “relied” upon by the witnesses. Invoices can, of course, be subpoenaed, but often oral examination is required to discover whether the invoices have been paid, whether they are contingent, or whether payment flows to the personal benefit of the expert witnesses. Inquiring into what “facts or data” were provided by retaining counsel can be attempted by written discovery, but the written responses will likely be hedged and unclear, and the responses will not distinguish which lawyer-provided “facts or data” were actually relied upon.

The FRCP clearly allow discovery into retaining attorneys’ provision of assumptions relied upon by expert witnesses, but clear, unrehearsed answers to questions about what was assumed and relied upon, as opposed to merely considered, are not likely to be forthcoming in written discovery. Furthermore, if there will be any fair opportunity to explore the significance of relying upon counsel’s assumptions, only a deposition will likely allow for the extemporaneous, first-person expression of expert witnesses’ opinions. Questions into expert witnesses’ opinions based upon hypothetical questions that contradict the assumptions given, or into opinions about the level of confidence or knowledge witnesses have about the correctness of the assumptions, are likely to be effective only in face-to-face encounters.

There are important additional reasons for taking expert witness depositions, not addressed in Joseph’s article. Litigation-savvy expert witnesses will often glibly assert that they have “considered” all the relevant studies, data, and facts. If written discovery is propounded to inquire whether a study omitted from the “consideration” list in the FRCP report was not considered, the study, if meaningful, will be added to the list in the written response with a feeble excuse that it was inadvertently omitted from the list. And the omission will likely be judged harmless because the party seeking discovery obviously knew about the omitted study already. Written discovery into what studies, data, or facts were considered but not relied upon will also yield highly rehearsed answers, and interrogatories will not permit inquiries into the fine details of key studies.

The pertinent sections of the FRCP do not require expert witness reports to distinguish what the witnesses have considered from what they have actually relied upon. Written discovery could be propounded, but again, it will not likely yield clear answers such as might be had with follow up inquiry into what was considered but not relied upon, and why was reliance rejected. The deposition upon oral examination has the benefit of permitting follow up questions into why some studies were relied upon for some parts but not others, or were considered but completely excluded from actual reliance. The opportunity to field incoherent, inconsistent rationales for inclusions and exclusions that establish expert witness cherry picking will be lost without the face-to-face encounter allowed by oral examination.

With some courts engaged in retrograde refusal to apply Rule 702 as enacted, some expert witnesses have been encouraged to employ vague, invalid, and unreliable methodologies, such as the so-called “weight of the evidence” approach. Oral examination will be necessary to establish expert witnesses’ weighting considerations, their inclusion and exclusion criteria, and to test their consistency in applying these considerations and criteria, across the entire evidentiary base for conclusions.

Concessions to Be Obtained

Written discovery is not well suited to inquire into general principles of interpreting data and studies, data integrity and validity, and validity of inference.  Interrogatories are too difficult to draft in sufficient detail to permit setting up an examination that will lead to the disqualification of the expert witness under Rule 702.  Obtaining concise, clear concessions about basic methodological principles is crucial to structuring persuasive cross-examinations.  Of course, if the deponent balks at accepting generally accepted principles, then this testimony is filed under Rule 702 motion, rather than trial cross-examination.

Furthermore, written discovery is poorly suited to identify whether expert witnesses have subject-matter weaknesses.  Interrogatories are the wrong discovery tool to conduct pop-quizzes on arcane statistical and scientific methodologies. Lawyers rightfully do not want to get into show-game style quizzes to test expert witnesses’ understanding of the esoteric, but important, methodologies used in the studies relied upon, in front of a jury. Rule 26 reports rarely announce that witnesses have had no meaningful training in statistics and that they have no idea what assumptions were made in various statistical analyses or tests in the studies that they have embraced and relied upon for their opinions.

Expert witnesses have social and professional connections not always apparent from their curriculum vitae, their Rule 26 reports, or their websites. Expert witnesses are not likely, for instance, to disclose that they are Marxists, who believe that corporations are evil and mercenary, and cannot be trusted to tell the truth in litigation.[2]

As noted, the FRCP requires disclosure of facts or data considered, which disclosure is usually inadequate to permit distinguishing what was actually relied upon in forming opinions. But what about opinions considered or relied upon? FRCP does not address reliance upon opinions; nor does Rule 703. Expert witnesses may contend that their opinions are not “based upon” others’ opinions, but that their opinions are strengthened and corroborated by the opinions of others. The FRCP do not specifically call for disclosure of opinions relied upon by retained expert witnesses, and adversary counsel can be trusted to argue that there were no obligations to disclose opinions or the identity of “authoritative” treatises and publications. If there is no entitlement to disclosure, there can be no surprise and prejudice.

Interpreting the scope of the report may not be as clear as Joseph suggests.  Rule 26 reports usually contain some opinions with sufficient breadth and generality that foregoing depositions becomes a game of Russian roulette.  Trial judges may not look kindly upon “scope of the report” objections, made at trial, when the objecting counsel had the opportunity to conduct an examination, and the report language is sufficiently broad to intimate the witness’s opinion at trial. Judges seem to have great hindsight vision, and they may well distrust counsel’s objections as a different sort of sandbagging. An entire strategy of restraint may be sunk by a quick, discretionary ruling on “scope of the report,” which often will favor the proponent of the witness.

Joseph is correct that many depositions fail to accomplish much, but such failures are not the result of how wonderful the revised FRCP are.  Failed depositions are more likely to result from the lack of preparation, creativity and knowledge of counsel in carrying out coherent, effective depositions.


[1] See Primus v. United States, 389 F.3d 231, 234 (1st Cir. 2004); Vaughn v. City of Lebanon, 18 F.App’x 252, 263 (6th Cir. 2001); Musser v. Gentiva Health Services, 356 F.3d 751, 758 (7th Cir. 2004). See also Design Strategy, Inc. v. Davis, 469 F.3d 284, 296 (2d Cir. 2006) (characterizing exclusion as discretionary, but upholding district court’s exclusion).

[2] Such as may be seen with expert witnesses who belong to the Committees of Correspondence for Democracy and Socialism, a branch of the Communist Party USA, formed in 1992, after the demise of the Soviet Union.