Non-Testifying Consultant Subject to Discovery Where Testifying Expert Relied on Consultant’s Work

In Jackson v. Tesla, Inc., 2024 WL 5011620 (N.D. Ca. Dec. 6, 2024), the court held that the work of a non-testifying consultant that was provided to a testifying expert was discoverable.

The non-testifying consultant reviewed unintended acceleration complaints in a federal (NHTSA) database.  The consultant used criteria supplied by plaintiffs’ testifying expert, Dr. Singer.  The review was to separate “confirmed” unintended acceleration claims from those that were merely “suspected.”  Dr. Singer relied on the consultant’s work to support his opinion that Tesla vehicles had a higher rate of this problem than other vehicles.

Plaintiffs did not disclose the identity of the consultant or the work performed; however, it came out in Dr. Singer’s deposition. Nevertheless, plaintiffs instructed Dr. Singer not to answer questions about the consultant’s identity or communications about the consultant’s work.  Plaintiff did produce some documentation about the criteria Dr. Singer had developed.

Tesla moved to compel the whole ball of wax – identity, a deposition, all documents and communications, invoices, etc. Id. at *1.  Plaintiffs’ offered half a loaf.

Fed.R.Civ.P. 26(a)(2) governs discovery of expert testimony.  For a testifying expert, one  disclosable matter is the basis, facts, and data considered by the expert in forming an opinion.  The Jackson court quoted the Advisory Committee note stating that this is to be “interpreted broadly….”

Tesla argued for disclosure because Dr. Singer relied on the consultant’s facts and data.

Plaintiffs responded by asserting that Fed.R.Civ.P. 26(b)(4)(D) protects information related to experts employed only for trial preparation, except under exceptional circumstances as defined in the Rule. The court wrote:

Plaintiffs argue that there are no such exceptional circumstances here, as their non-testifying consultant “simply performed an administrative function under the direction of and according to search terms provided by … Dr. Singer.”

The Jackson court cited Ninth Circuit authority for the proposition that the non-testifying expert rule is not intended to impede discovery about testifying experts. Id. at *2. That precedent also suggested that any ordinary work product protection “would typically be waived where the materials are disclosed to a testifying expert.”

Applying those principles, the Jackson court explained that Dr. Singer had stated opinions that relied on the consultant’s assessment, and:

The record does not support plaintiffs’ assertion that the consultant merely performed an “administrative function” that required no analysis or judgment. Rather, Dr. Singer testified that while he supplied instructions to guide the consultant’s review of the VOQ database, he did not review all of the suspected UA claims to determine which were “confirmed,” and only checked “some” not large percentage of the data set to assess whether his instructions had been followed.

Dr. Singer was unable to answer some deposition questions, such as “how the consultant implemented his instructions.”  Id. at *2.

In brief summary, two of the important points are:

• “[P]laintiffs elected to disclose the consultant’s work to Dr. Singer, and Dr. Singer relied on that work as support for his opinions. The consultant’s work forms part of the ‘basis’ of Dr. Singer’s expert opinion and is among the ‘facts or data’ he considered. Thus, Rule 26(a)(2)(B) requires disclosure of the consultant’s work….” Id.
• “Rule 26(b)(4)(D) [the non-testifying expert rule] is not implicated in these circumstances. Plaintiffs have not retained or employed a non-testifying consultant solely to assist with trial preparation, but have instead offered an expert opinion by Dr. Singer that expressly relies on that consultant’s substantive work. Plaintiffs’ refusal to permit discovery regarding how the work was performed effectively prevents Tesla from testing whether the VOQ analysis was done according to Dr. Singer’s instructions. More importantly, it prevents Tesla from exploring the reliability of Dr. Singer’s principal opinion….” Id. at *3.

The Jackson court ordered both substantial disclosures regarding the consultant and a brief re-deposition of Dr. Singer. Id.