Corporate defendants are frequently faced with a quandary—is the company’s highly sophisticated professional employee simply a fact witness or does their anticipated testimony propel them into the world of expert discovery? The individual knows the business inside and out, and typically has a comprehensive understanding of the entire industry, but the legal parameters of whether they qualify as a lay witness or expert witness in this context is not always clear. And either designation presents potentially significant risks. Companies must proceed with caution and consider the following before proceeding.

1. The Nature of the Testimony: Lay Witness vs. Expert Witness

The first consideration is whether the witness crosses the line from a lay witness under Federal Rule of Evidence 701 to an expert witness under Federal Rule of Evidence 702. Lay witnesses provide testimony based on their direct experiences and perceptions. For instance, a lay witness may describe observations of a scene, or the behavior of individuals involved, as these are assessments rooted in common experience. These observations may encompass various elements, such as the appearance or identity of persons or objects, the manner actions were carried out, the perceived competency of a person engaged in a particular task, or sensory assessments like lighting, sizes, sounds, weights, and distances.

The scope of a lay witness’s testimony is restricted to avoid encroachment upon domains reserved for expert witnesses.[1] Expert witnesses are individuals who are qualified by knowledge, skill, experience, training, or education who are able to testify in the form of an opinion if the expert’s scientific, technical, or other specialized knowledge will help the trier of fact (the court or the jury) understand the evidence or determine a fact at issue. Expert witnesses are held to a higher standard before testifying in court, and the testimony must be based on sufficient facts and data to ensure credibility and reliability. For example, qualified expert witnesses may testify about matters involving DNA evidence, manufacturing defects, accident reconstruction, forensic accounting matters, or medical procedures so long as the witness has the accepted qualifications, the testimony is relevant and reliable, and the methods used to form a conclusion are generally acceptable in the field. Experts may be retained specially for a case without any prior connection or knowledge of the specific parties or facts, or experts may be non-retained such as treating physicians or employee witnesses who have some relation to the underlying facts but also possess specialized or technical knowledge helpful to the trier of fact.

That is not to say that an employee witness’s specialized knowledge from experience in a specific business or profession automatically qualifies them as an expert under Rule 702. For example, most courts allow the owner or officer of a business to testify to the value or projected profits of the business without qualifying the witness as an expert. General industry knowledge or records reviewed in the regular course of business can be crucial factors in determining the type of testimony permitted. Courts must consider whether the testimony relies on expertise or specialized knowledge, and whether the facts presented are a result of mere tabulation versus extensive calculations. Lay witnesses can oftentimes testify to simple tabulation so long as the underlying information is not based on specialized knowledge, but the determination of whether specialized knowledge or extensive calculation is required is not often clear. An extensive analysis is necessary to avoid the possible inadvertent exclusion of testimony.

2. The Scope of the Non-Expert Disclosure

Once the witness falls into the category of a non-retained expert, the requirements of Federal Rule of Civil Procedure 26(a)(2) are triggered. Unlike retained experts, non-retained experts are not required to provide a detailed report, but they still must be disclosed with certain requirements. Rule 26(a)(2)(C) requires the disclosure to state:

(1) Subject Matter of Anticipated Testimony; and

  • Summary of the Facts and Opinions to Which the Witness Expects to Testify.

The exact boundaries of this disclosure can vary wildly from court to court, making it vital that litigants consult both local rules and law regarding disclosures. This issue frequently arises in the context of a treating physician where, on one hand, some courts have concluded that the disclosure of a non-retained expert requires more than stating a witness’s connection to a case or a reference to medical records.[2] On the other hand, courts have found the disclosure sufficient when a party merely listed the main points of a non-retained expert’s testimony and provided the associated medical records.[3] Regardless, a non-retained expert must be disclosed with adequate notice and sufficient detail to allow for thorough preparation by the opposing party. Providing adequate notice and sufficient detail typically necessitates more than merely referencing the broad topic of the anticipated testimony—it requires a specific and in-depth disclosure of the content. Generally, this can be accomplished by outlining the main points of the anticipated testimony along with the pertinent facts and opinions underpinning it. This procedural protection operates in a manner akin to, but not as robust as, the safeguards applied to retained expert witnesses.

3. The Potential Discoverability of Privileged Communications

Like retained experts, non-retained experts must also disclose the information and assumptions they relied upon. Unlike retained experts, however, the protections of Rule 26(a)(4)(C) may not apply. Rule 26(a)(4)(C) safeguards communications between a party’s attorney and “any witness required to provide a report.” Noticeably absent from the rule is protection for non-retained experts. This was not an oversight as the advisory committee note to this section states the rule, “does not itself protect communications between counsel and other expert witnesses.” (emphasis added).

Many courts therefore find a party has waived attorney-client and work product protections for documents considered in connection with the non-retained expert’s testimony. Others go further, suggesting that the term “considered” should be interpreted broadly as covering everything the expert was exposed to and not only what the expert actually relied upon in forming their opinions. Some courts have even ordered the disclosure of communications between outside counsel and the non-retained expert employee. Further, if a disclosure is not sufficiently clear or narrowly tailored, the required production may include all of the witness’s knowledge and experience directly related to the litigation. Courts justify this requirement by suggesting it may be difficult to distinguish between a non-retained expert’s impressions relating to their work as a fact witness and their expert opinions. Courts warn that opposing counsel must have the opportunity to expose any “attorney-caused bias.”[4] Each specific jurisdiction is different, warranting an extensive review of the potential privilege waiver before leaning on the sophisticated employee as a non-expert witness.


Determining the status of witnesses is critically important and carries inherent risks. Failing to designate a witness as a non-retained expert could have unanticipated negative consequences if the court later deems their testimony to be of an expert nature, potentially barring vital evidence from admission at trial. Once trial is underway, it is typically too late to reclassify a witness from layperson to expert, or from non-retained expert to retained expert. Therefore, parties may choose to preemptively categorize a borderline witness with potential expert-level knowledge as a non-retained expert prior to trial to avoid this risk. This decision, however, exposes the witness, and their employer, to more rigorous legal scrutiny. It also allows the opposing side to gain insight into the expert’s projected testimony and potentially privileged information. Striking the right balance between the danger of witness exclusion and the advantage of detailed disclosure is a critical aspect of strategizing witness classification.

For more information regarding the classification of employee witnesses, please contact Kate Ledden, Maddie Kincaid, or another member of our Healthcare Litigation team.

[1] Fed. Ins. Co. v. Sammons Fin. Grp., Inc., No. 408CV00288SMRHCA, 2014 WL 11514685, at *3 (S.D. Iowa Sept. 15, 2014).

[2] See, e.g., Anderson v. Bristol, Inc., 936 F. Supp. 2d 1039, 1059–60 (S.D. Iowa 2013) (finding that Rule 26(a)(2)(C) requires more than stating witness’s connection to case or reference to medical records, absent summary of witness’s expected testimony).

[3] See, e.g., Oskar v. United States, 4:14–CV–04144–KES, 2017 WL 2937598, at *3 (D.S.D. July 10, 2017) (finding that expert physicians were properly disclosed under Rule 26(a)(2)(C) where party disclosed that each physician would testify as to party’s health before surgery, the actual surgery the physician performed, and the party’s prognosis); Cattanach v. Burlington N. Santa Fe, LLC, Civil No. 13-1664 (JRT/JSM), 2015 WL 5521751, at *12 (D. Minn. Sept. 18, 2015) (concluding that treating physician was adequately disclosed where party produced medical records of the party’s only visit with physician).

[4] City of Mankato, Minnesota v. Kimberly-Clark Corp., No. CV 15-2101 (JRT/TNL), 2019 WL 4897191, at *11 (D. Minn. May 28, 2019).