When an expert plays both a consulting and a testifying role, it is often difficult to determine if the expert’s former role resulted in access to materials that might affect the expert’s testimony—thus rendering the materials fair game for discovery by the adversary.
In Construction Industries Services Corp. v. Hanover Insurance Co., 206 F.R.D. 43, 54 (E.D.N.Y. 2002) (citation omitted), the court explained that “any ambiguity as to the role played by the expert when reviewing or generating documents should be resolved in favor of the party seeking discovery.” In examining the dual-role expert in the case before it, the court concluded that the difficulty in segregating documents reviewed by the expert meant that “the plaintiffs should either turn over the documents or get a new expert.” Id. at 55.
Parties hoping to use the same expert in both a consulting and a testifying role should remember that any ambiguity about materials the expert reviews will be resolved in favor of discovery.