Courts Explore Testifying Experts’ Obligation to Disclose Documents

October 7, 2009

Most courts hold that testifying experts must disclose all documents that they reviewed in preparing to testify, not just the documents upon which they relied. However, this simple rule becomes much more complicated when testifying experts play multiple roles, or testify frequently.

In W.W. Transport, Inc. v. Gem City Ford, Inc., Case No. 2:07CV46-JCH, 2009 U.S. Dist. LEXIS 70040, at *2 (E.D. Mo. Aug. 11, 2009), one partner in an accident reconstruction firm assisted the defendant as a testifying expert, while another partner acted as a “non-disclosed consulting [non-testifying] expert witness.” The non-testifying expert provided a chronology to the testifying expert, and also assisted him in taking measurements and photographs. The plaintiff claimed that this interaction required the non-testifying expert to produce all of his documents too, but the court denied the plaintiff’s request ‑‑ after concluding that the non-testifying expert had not disclosed any of his opinions, information, or file materials to the testifying expert. Two weeks later, a court dealt with a defendant’s testifying expert’s billing records generated in a different (but related) case. In Dale K. Barker Co. v. Sumrall, Case No. 2:03cv903, 2009 U.S. Dist. LEXIS 75323, at *10 (D. Utah Aug. 24, 2009), the court ordered the testifying expert to produce his billing records from that other case ‑‑ because “it appears that the two cases have similar issues,” and the records “may have some relevance to the instant case.”

A litigant hiring testifying experts must examine what other roles they or their partners are playing in the case, or have played in other related cases.