Trick or Treater? The difficulties in treating physicians’ testimonies

Photo by National Cancer Institute on Unsplash

Patrick Mullinger, Associate Member, University of Cincinnati Law Review

I. Introduction         

The treating physician: one of the most important people in your life when you’re sick or injured, and one of the most difficult witnesses when determining what testimony is allowable in a court. In the federal courts, Fed. R. Civ. P. 26(a) governs witness testimonial. Typically, treating physicians are determined to be lay fact witnesses, and thus, their testimony is limited. However, during a trial, such testimony often extends past the permissible scope. The 2020 Amendments to Rule 26 make it even more imperative for attorneys to become familiar with the amendments.[1] In trial, it is extremely important for an attorney to acknowledge the true scope of their treating physician’s testimony and be diligent when addressing these kinds of situations.

This article will walk through various difficulties in the “treater v. expert” classification of a witness. Part II will analyze the procedural steps necessary when identifying a treating physician versus an expert witness in Fed. R. Civ. P. 26. Then, Part III will analyze case law in the Sixth Circuit showing the difficulty in identifying when a treating physician’s testimony extends past what is allowed. Part IV will focus on the importance of a court ensuring that a treating physician does not extend their testimony beyond the allowable scope under the Federal Rules of Civil Procedure.

II. Federal Rule of Civil Procedure 26 governs the necessary steps when identifying an expert witness

Identifying an expert witness requires several steps before their testimony is allowed at trial. The very first step in litigation is to disclose any individual who is likely to have discoverable information.[2] These initial disclosures are due 14 days after the parties have a Rule 26(f) conference,[3] now required under the recent Rule 26 amendments,[4] which is when expert witness are disclosed. Under Rule 26(a)(2)(A), a party must disclose the identity of any witness it may use at trial to present evidence under Fed. R. Evid. 702, 703, or 705 to the opposing party.[5] These witnesses, however, may have different disclosure requirements under Fed. R. Civ. P. 26 (B) or (C). To be disclosed as an expert witness retained specifically for litigation, the party disclosing the expert must submit a written report prepared and signed by the witness.[6] These reports must contain several elements which allow the expert to opine on the incident at hand.[7]

However, there is a wrinkle. Rule 26(a)(2)(C) was added in 2010 and explains that some expert witnesses do not need to provide written reports.[8] Instead, such witnesses must only state the subject matter they are expected to present as evidence and a summary of the facts and opinions to which they are expected to testify.[9] This rule aligns with the 1983 amendments to limit unduly expensive discovery requirements.[10] The rule governs witnesses who are not providing any expert testimony, as expert witnesses must comply with Rule 26(a)(2)(B). A treating physician would be classified as a witness who does not need to create an expert report.[11] While it may seem menial to differentiate between an expert witness and a treating physician, cases are often decided based on the testimony of one treating doctor giving opinions on issues that should be given by experts.

III. The scope of a treating physician’s testimony is unclear under Sixth Circuit case law.

As stated above, a treating physician is treated as a lay fact witness under the Federal Rules of Civil Procedure.[12] However, the rules neither offer any clarity on the situation where a treating physician is opining as an expert witness, nor do they address when a treating physician is retained or specifically employed as an expert witness.[13] Current case law in federal courts, as well as state courts, is murky at best and fails to establish a bright line rule. This leaves an immense amount of uncertainty around a procedural issue that may be dispositive of a case.

When determining if a treating physician opines beyond the scope of their allowable testimony, courts consider a variety of factors. In Fielden v. CSX Transp., Inc., 482 F.3d 866 (6th Cir. 2007)—a case decided before the Rule 26 amendments—the court weighed whether treating physicians are subject to Rule 26(a)(2)(B) and concluded that the plaintiff’s treating physician was not required to provide a report.[14] The factors applied in Fielden were whether: (1) the physician was retained to provide expert testimony; (2) the physician formed his or her opinions at the time of treatment or in anticipation of litigation; (3) the lack of a full expert report would implicate Rule 26’s purpose of avoiding surprise and unnecessary depositions; (4) any expert opinion on causation was formed during the course of treatment; and (5) the claimed physician will testify to issues beyond those ordinarily present in his or her medical training.[15] A treating physician’s testimony on causation is only allowable in certain circumstances, such as when the physician formed their testimony as part of the patients diagnosis and treatment based on the actual treatment of the patient and the records they reviewed up to and including their own treatment.[16] The court in Fielden noted that some other courts require a Rule 26(a)(2)(B) expert report if the testimony strays from the core of the physician’s treatment.[17]

However, the cases to which the Fielden court cites were all decided prior to the 2010 Amendment to Rule 26.[18] In Avendt v. Covidein, the Eastern District of Michigan stated that the Sixth Circuit has not decided on the disclosure requirements of treating physicians as expert witnesses in light of subsection (a)(2)(C).[19] In Avendt, the doctor was determined to be giving testimony based on his personal knowledge of and observations made during the course of Plaintiff’s treatment, and the doctor was not given any additional medical records outside the records made during the course of treatment.[20] The court thus allowed his testimony as an expert witness subject to Rule 26(a)(2)(C) for reasons that his testimony will not lead to any surprise testimony on this subject.[21]

On one hand, Sixth Circuit District Courts continue to apply the Fielden factors, while on the other hand, courts apply the plain language of Rule 26. In the Avendt opinion, the Eastern District of Michigan cited Tyler v. Pack Indem. Co., another decision within the Sixth Circuit, in which the other court noted that the Fielden factors are instructive of the scope of a physician’s testimony.[22] In Tyler, the Eastern District of Michigan applied a similar analysis as the Fielden court by looking at the scope, substance, and source of the intended testimony.[23] In contrast, other districts use the plain language of the Rule if testifying physicians are “specifically retained or specially employed to provide expert testimony in the case or one whose duties as the party’s employee regularly involve giving expert testimony.”[24] In Wilson v. Hill, the Southern District of Ohio stated that the treating dentists testimony would necessarily qualify as one whose testimony would be subject to the disclosure requirements of Rule 26(a)(2)(C).[25]

The factors listed in Fielden seem to be the governing analysis used in Sixth Circuit opinions.[26] In Barnes v. CSXT Transp., Inc., No. 3:13-CV-00525-DJH, 2017 U.S. Dist. LEXIS 53650, 42 (W.D. Ky. 2017), the court applied the Fielden factors to determine the scope of the testimony.[27] Multiple doctors were allowed to testify because the doctor based their opinions on ordinary medical training and only considered their own notes of the plaintiff’s treatment.[28] Additionally, none of the conclusions made by the physicians were made after the treatment, and there was no indication of involvement of counsel.[29]

While it may seem like the Sixth Circuit grants a treating physician significant leeway to opine as an expert witness without a Rule 26(a)(2)(B) report, their testimony is extremely limited without an expert report, especially in negligence cases where a breach of an owed duty causes actual damages.[30] Causation is one of the most difficult elements to prove, and thus, the Sixth Circuit held that the causation element may not be opined on by a treating physician unless the causation was based on the facts observed personally within the scope of the Plaintiff’s treatment.[31]

IV. The Federal Rules of Civil Procedure and subsequent cases do not go far enough to limit a treating physician when opining on causation

One extremely important issue in civil cases surrounding physician testimony is the limitation of expert testimony solely to the scope of their treatment. A treating physician who opines on the causation elements of a traumatic injury may entirely alter the course of litigation, not to mention increase costs of the party defending against the treating physician’s statements. This is important because doctors carry extreme credibility in the eyes of the jury due to their position and title. Even if their testimony is struck from the record, the jury may still be biased, as a jury cannot “unhear” what has been said. In no way is this stating that a treating physician should not be able to testify, but courts must be vigilant in preventing a doctor from extending beyond the scope of their allowable testimony under the Federal Rules.

While the Federal Rules of Civil Procedure do take some steps toward limiting the testimony of a treating a physician, they do not go far enough. First and foremost, there is no mention of a fact witness with heightened knowledge regarding a specific field in Rule 26.[32] The only mention of this issue is found in the notes following the rule, which reference a treating physician expert.[33] Without a guiding light, the courts must make an educated guess as to what this means, which often may lead to unfair outcomes. A treating physician who extends their testimony beyond the scope of their treatment will also cause difficulty for opposing counsel to know exactly what the testimony would be. To rebut the treating physician’s testimony that extends into expert witness testimony would force opposing counsel to hire an expert just to refute something that should not have been admissible in the first place. Moving forward, this treating physician exemption may cause difficulty in litigation, as the rates for a rebutting expert witness may increase as the need for them skyrocket. Additionally, a treating physician’s testimony may be granted more authority by a jury than an expert witness, even when the expert is specialized in the field, while the treating physician provides just general medical knowledge. This may taint the jury’s view of the true value of a case, and thus take up extreme amounts of judicial time during an appeals process.

These unfair outcomes go manifestly against what the legal profession should stand for. Without a firm analysis to protect the parties in litigation, courts have no guidance on the allowable scope of a treating physician’s testimony. The “surprise testimony” referenced in the third factor of a Fielden analysis may be one of the most crucial to display the possible effects of allowing a treating physician to testify. Without access to how a treating physician came to their conclusion, nor the processes they took in their diagnostic reasoning, the opposing party will have no possible grounds to possibly strike using a Daubert or Frye standards.[34] If a party is unable to know what the testimony will be until a deposition, then they will not be able to bring these challenges, thus costing their clients’ money and the court time. Additionally, courts must be on guard for treating physicians extending their testimony into fields beyond the scope of their proper credentials.[35] If a court lets its guard down, the jury risks perversion through irrevocable bias.

A simple solution would be for the legislature to amend Rule 26(a)(2). This new rule could clear the issues surrounding the problems of a retained or specifically employed expert, as was the issue in Barnes and Amos.[36] The clarity of this issue is difficult to resolve, however, because courts have stated that the mere nonpayment or compensation is not dispositive of the issue of a specifically retained expert.[37] To say the least, determining a treating physician is about as clear as mud. A potential solution would be to explicitly state that a Rule 26(a)(2)(C) witness may not opine to any issues of causation, or to medical records not used in actual treatment, without first a Rule 26(a)(2)(B) report. Essentially, the proposed Rule will explicitly limit the testimony possible of a treating physician but will not force the treating physician to complete a report simply to present their reasoning for treatment.

Another possible recommendation would be to adopt the Fielden factors as an amendment to Rule 26(a)(2)(C). Using the factors would easily place a balancing test amongst Federal courts, and likely state courts would adopt the rule to line up seamlessly. Again, the suggestion of putting the Fielden factors likely will not solve all issues, especially considering a treating physician’s testimony, but it may grant clarity to lawyers working with the rule to understand the scope of testimony allowed. The establishment of clear guidelines would lead to additional accountability amongst attorneys to follow the Federal Rules of Civil Procedure and could result in the development of more uniformly applicable best practices within the profession surrounding physician testimony.

V. Conclusion

The challenges that arise from a treating physician’s testimony extending past the scope of their treatment are unlikely to go away anytime soon. While some aspects of the issue may be resolved by an amendment to Fed. R. Civ. P. 26, such an amendment is unlikely to clarify all the issues presented. The duty of clarification rests on the legislature to determine the scope of a treating physician’s testimony. Not only must the courts clarify the appropriate scope, but also must be diligent in their efforts to ensure no injustices arise from a physician extending themselves into areas outside the treatment.

[1] See Fed. R. Civ. P. 26.

[2] See Fed. R. Civ. P. 26(a)(1)(A) detailing that, even before discovery, a lawyer must provide: (i) the name and, if known, the address and telephone number of each individual likely to have discoverable information – along with the subjects of that information – that the disclosing party may use to support its claims or defenses, unless the use is solely for impeachment. This is used to facilitate the discovery process and make it much more efficient and cheaper to work through litigation, a bonus for the defense, the plaintiff, and the courts. 

[3] See Fed. R. Civ. P. 26(a)(1)(C). Fed. R. Civ. P. 26(f) is a conference for the parties and court to lay the timeline for the litigation proceedings, including when expert witnesses will be disclosed.

[4] See Fed. R. Civ. P. 26(a)(1)(C). The prior rule did not have this requirement.

[5] See Fed. R. Civ. P. 26(a)(2)(A). Fed. R. Evid. 702 defines an expert as a witness qualified by knowledge, skill, experience, training, or education, and may testify to (a) their scientific, technical, or other specialized knowledge that will help the trier of fact; (b) testimony based on sufficient facts or data; (c) product of reliable principles and methods; and (d) the expert reliably applied the principles and methods to the facts of the case. Fed. R. Evid. 703, in part, states that an expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. Fed. R. Evid. 705, in part, states that an expert may state an opinion without first testifying to the underlying facts or data but may be required to disclose the facts or data upon cross-examination.

[6] See Fed. R. Civ. P. 26(a)(2)(B). Rule 26(a)(2)(B) also stipulates that if an expert is regularly involved in giving expert testimony for the party, then they must also provide an expert report.

[7] See Fed. R. Civ. P.26(a)(2)(B)(i)-(vi). (i) states that all the opinions the expert has and the basis for them; (ii) is the facts used in forming them; (iii) is any exhibit used; (iv) the witness’s qualifications, including publications; (v) is a list of other cases they were used as an expert; and (vi) a statement of the fee’s charged by the expert. Additionally, issues may arise in the discoverability of documents produced to experts, should their testimony be used.

[8] See Fed. R. Civ. P. 26(a)(2)(C).

[9] See Fed. R. Civ. P. 26(a)(2)(C)(i) and (ii).

[10] See Notes of Advisory Committee on 2015 Amendments to Fed. R. Civ. P. 26.

[11] See Notes of Advisory Committee on 1993 Amendments to Fed. R. Civ. P. 26.

[12] See Fed. R. Civ. P. 26.

[13] See Barnes v. CSXT Transp., Inc., W.D. Ky. No. 3:13-CV-00525, 2017 U.S. Dist. LEXIS 53650, 36-37 (W.D. Ky. Apr. 7, 2017); See also Amos v. W.L. Plastics, Inc., No. 2:07-CV-49 TS, 2009 U.S. Dist. LEXIS 107271, 2009 WL 3854980 at 2 (D. Utah Nov. 17, 2009).

[14] See Fielden v. CSX Transp., Inc., 482 F.3d 866, 869-72 (6th Cir. 2007).

[15] Id. at 870-73; See also Jett v. CSX Transportation Inc, No. 2007-162 (WOB), 2009 U.S. Dist. LEXIS 28750, 2009 WL 899626 at *3 (E.D. Ky. 2009) (discussing Fielden, 482 F.3d at 870-73).

[16] Id. at 871.

[17] See Fielden, 482 F.3d at 870-71.

[18] See Avendt v. Covidien Inc., No. 11-cv-15538, 2014 U.S. Dist. LEXIS 175843, 9 (E.D. Mich. 2014).

[19] Id. at 10.

[20] Id. at 12.

[21] Id. at 13.

[22] Id.

[23] See Avendt v. Covidien Inc., No. 11-cv-15538, 2014 U.S. Dist. LEXIS 175843, 9 (E.D. Mich. 2014). (citing Tyler v. Pac. Indem. Co., No. 10-cv-13782, 2013 U.S. Dist. LEXIS 6898, 2013 WL 183931, at *2 (E.D. Mich. 2013)).

[24] See Wilson v. Hill, No. 2:08-CV-552, 2012 U.S. Dist. LEXIS 43246, 2012 WL 1068174, at *5-6 (S.D. Ohio 2012).

[25] Id.

[26] While often referenced as the “treating physician” exemption, it is not solely for a medical incident. The exemption has been applied to computer professionals (See Linux One Inc. v. Inktomi Corp., No. C03-01598 JW, 2004 U.S. Dist. LEXIS 30804, 2004 WL 5518163 (N.D. Ca. Aug. 26, 2004)) all the way to elevator employees involved in the remodeling of a historic hotel (See Burgundy Development, LLC v. The Lathan Company, Inc., No. 12-1387, 2012 U.S. Dist. LEXIS 180518, 2012 WL 6674413 at 2 (E.D. La. Dec. 20, 2012)).

[27] See Barnes, 2017 U.S. Dist. LEXIS 53650, 43-39.

[28] Id.

[29] Id. at 51.

[30] See Negligence, Black’s Law Dictionary (11th. Ed. 2011).

[31] See Roberts v. Solideal Tire, Inc., E.D. Ky. No. 06-14-DLB, 2007 U.S. Dist. LEXIS 75512, 16 (E.D. Ky. Oct. 10, 2007); See also Lindon v. Kakavand, E.D. Ky. No. 5: 13-26-DCR, 2014 U.S. Dist. LEXIS 161986, 9-10 (E.D. Ky. Nov. 18, 2014) (limiting a treating doctor’s testimony which was outside the scope of treatment to criticism of another doctor).

[32] See generally Fed. R. Civ. P. 26.

[33] See Notes to 1993 Amendments of Rule 26.

[34] Daubert refers to Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (June 28, 1993), and Frye refers to Frye v. United States, 293 F. 1013 (D.C. Cir. Dec. 3, 1923). Both cases, in pertinent part, identify factors in assessing an expert witness’s credibility.   

[35] See Andrew Lehmkuhl, Yagodinski: Another Reminder to Keep Experts in their Lane, PORTER RENNIE WOODARD KENDALL, LLP (Aug. 12, 2021), [], for a discussion on the implications of allowing an expert to testify beyond their medical scope.

[36] Supra note 10.

[37] Id.; see also Charles v. Print Fulfillment Services, LLC, No. 3:11-CV-553-H, 2014 U.S. Dist. LEXIS 6814, at 2-3 (W.D. Ky. Jan. 10, 2014) (“As a preliminary matter, the court concludes that the relevant question regartding the applicability of Rule 26(a)(2)(B), is not whether money has changed hands, or whether an employment relationship otherwise exists, but whether the witness will provide expert testimony … as opposed to opinion testimony from a lay witness”).


  • Patrick Mullinger decided to focus mostly on small issues in Civil Procedure, which caused vigorous discussions at his firm Porter Rennie Woodard and Kendall, LLP. Patrick finds these issues practical to discuss as the writing on these issues is sparse. Writing on these issues allowed him to expand his opinions on how the rules should and could operate. Writing for the UC Law Review gave Patrick an avenue to deepen his thinking of niche issues in the Federal Civil Rules of Procedure, and he found himself enjoying the deep legal research necessary to put forth the best drafts. Patrick hopes to continue learning more about Civil Procedure in his legal career as a civil litigation attorney after graduation.

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