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September 25, 2013 Articles

The 2010 Amendments to Expert Discovery Rules: Yesterday, Today, and Tomorrow

Leverage the benefits of your expert and expose the weaknesses of your opponent's expert

By Joseph L. Meadows and Michael L. Kuppersmith

A case can sometimes be won or lost by an expert. Even the simplest of cases may be enhanced materially by an expert’s explanation of an issue involving liability or damages. Mastering the expert discovery rules (Federal Rule of Civil Procedure 26) is important to leveraging the benefits of one’s expert and exposing the weaknesses of the other side’s expert. The expert discovery rules underwent a major overhaul in 2010—the most extensive such change in almost 20 years. And the discovery rules are in the midst of being revised again. So what changed in 2010? What is the state of play for expert discovery now? And what changes are on the horizon?

The Basics

As a general matter, experts are permitted to testify outside their personal knowledge and provide opinions on matters within their field of expertise. Fed. R. Evid. 702 & 703. Their opinion testimony must be based on sufficient facts or data and the product of reliable principles or methods, and those principles or methods must be applied reliably to the facts of the case. Fed. R. Evid. 702; see also Kumho Tire Co. v. Carmichael, 526 U.S. 137 (1999); Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579 (1993). During discovery, most testifying experts must disclose all opinions they will express, the basis and reasons for the opinions, the facts or data “considered” in forming the opinions, and any exhibits that will be used to summarize or support the opinions. Fed. R. Civ. P. 26(a)(2)(B). Unless otherwise ordered or stipulated, these disclosures must be made at least 90 days prior to trial or, if solely to rebut expert evidence presented by the other side, at least 30 days after the other side’s disclosure. Fed. R. Civ. P. 26(a)(2)(D).


Going back at least to 1993, the scope of materials “considered” by the expert (and hence discoverable) has always been far-reaching. “Considered” meant almost anything the expert “generates, reviews, reflects upon, reads, and/or uses in connection with the formulation of his opinions, even if such information is ultimately rejected.” Fialkowski v. Perry, No. 11-cv-5139, 2012 WL 2527020, at *3 (E.D. Pa. June 29, 2012) (quoting Synthes Spine Co. v. Walden, 232 F.R.D. 460, 463 (E.D. Pa. 2005)); see also Reg’l Airport Auth. of Louisville v. LFG, LLC, 460 F.3d 697, 714–17 (6th Cir. 2006) (following the  “overwhelming majority” rule that all information provided to testifying experts is discoverable, including privileged communications and attorney work product, regardless of ultimate reliance by the expert); 8 Charles A. Wright, Arthur R. Miller, Mary Kay Kane & Richard L. Marcus, Federal Practice and Procedure § 2016.5 (3d ed. 2012) (noting that the expert discovery rules “required disclosure of most or all that was shown to the expert witness”). Accordingly, counsel carefully selected the information to be shown to the expert, and counsel often discouraged the expert from conducting widespread research and preparing written materials without first seeking guidance. Nearly anything the expert “considered” was fair game in discovery under the rationale that “information considered, but not relied upon, can be of great importance in understanding and testing the validity of an expert’s opinion.” See Trigon Ins. Co. v. United States, 204 F.R.D. 277, 282 (E.D. Va. 2001). If the expert considered but ultimately rejected or failed to incorporate certain facts in the analysis, opposing counsel was eager to investigate why, and the expert had to be ready to defend all of his or her actions and decisions.

Still further, under the rules in place between 1993 and 2010, testifying experts were required to disclose data or “other information” they considered. Like the term “considered,” “other information” had a broad meaning. Draft reports, communications between counsel and expert, and any other reviewed materials likely were covered by the rules. See Proposed Rules, 137 F.R.D. 53, 89 (1991) (discussing how the 1993 amendments were designed to ensure the disclosure of more, rather than less, information for the purpose of reliability and credibility of expert testimony).Consequently, counsel often withheld materials from the expert in order to block disclosures to the other side—albeit at the risk of preventing the expert from examining materials that could further enhance the opinions or effectively prepare the expert for a deposition or trial. See G.P. Joseph, Trial Evidence in the Federal Courts: Problems and Solutions, ALI-ABA Course of Study (Oct. 20–21, 2005) (advising lawyers to curtail written communications with experts).


In 2010, the expert discovery rules were amended significantly. The requirement to produce “other information” was changed to the requirement to produce only “facts.” (The requirement to disclose all “data” considered by the expert remained unchanged.) As the advisory committee highlighted, this change in language was designed to curb disclosures of counsel’s work product, legal theories, and mental impressions. See Fed. R. Civ. P. 26 advisory committee’s note (2010 amend.); Int’l Aloe Sci. Council, Inc. v. Fruit of the Earth, Inc., No. 11-cv-2255, 2012 WL 1900536, at *1 (D. Md. May 23, 2012) (“The addition of Rule 26(b)(4)(C) is designed to protect counsel’s work product and ensure that lawyers may interact with retained experts without fear of exposing those communications to searching discovery.”) (quoting 2010 advisory committee’s notes); Allstate Ins. Co. v. Electrolux Home Prods., Inc., 840 F. Supp. 2d 1072, 1077–78 (N.D. Ill. 2012) (“The rule was amended in 2010 to require the disclosure of ‘facts or data’ rather than ‘data or other information,’ which made clear that disclosure of theories or mental impressions of counsel is not required.”). Courts have largely followed suit, finding that expert discovery after 2010 should be narrower. See Fialkowski v. Perry, No. 11-cv-5139, 2012 WL 2527020, at *3 (E.D. Pa. June 29, 2012); Allstate Ins. Co., 840 F. Supp. 2d at 1077–78.

Despite the language change—and the expectations of some commentators (see, e.g., Justin J. Hakala, “A New Day for Expert Discovery,” 47 Trial 6 (June 2011); Allegra J. Lawrence-Hardy & Laurance J. Warco, “Good News for Experts (And Attorneys Who Use Them),” Law360,Nov. 29, 2010)—the practical consequences of the 2010 amendments have not been so dramatic. Even though the amendments were intended to narrow the scope of expert discovery, the phrase “facts or data,” much like the term “considered,” has been “interpreted broadly to require disclosure of any material considered by the expert, from whatever source, that contains factual ingredients.” Fed. R. Civ. P. 26 advisory committee’s note (2010 amend.). In reality, expert discovery is basically the same as it was before the 2010 amendments, with two notable exceptions: The “drafts” of any expert report or disclosure are protected, and most communications between counsel and the expert are protected. Fed. R. Civ. P. 26(b)(4)(B) & (C). These protections apply “regardless of the form” the drafts and communications take. Id. Although these protections shield potentially useful information from disclosure, they permit the expert and counsel to work together more effectively without concern that everything they say or do is at risk of being exposed. For instance, an expert should be able to withhold communications with and analysis provided to counsel to refute the other side’s expert opinion or to prepare for that expert’s deposition. Int’l Aloe Sci. Council, Inc., 2012 WL 1900536, at *2 (protecting expert notes on other side’s expert report and for use by counsel in taking expert deposition).

The added protection for draft reports does raise questions, not all of which have been answered. Many courts hold that an expert’s notes, worksheets, and preliminary analyses do not need to be disclosed because these materials could be part of a “draft” report regardless of their form. See, e.g., Etherton v. Owners Ins. Co., Civ. No. 10-cv-00892-MSK-KLM, 2011 WL 684592 (D. Colo. Feb. 18, 2011) (protecting an expert’s “working notes” from disclosure because, inter alia, the trial preparation protections of the amended rules apply to drafts of any expert report, regardless of form). Other courts have held the same because these materials are like protected work product, and an expert need not produce everything necessary for the opposing expert to replicate the analysis. See, e.g., Helmert v. Butterball, LLC, No. 4:08CV00342, 2011 WL 3157180 (E.D. Ark. July 27, 2011) (“Nor is there any suggestion in Rule 26(a)(2) that an expert report is incomplete unless it contains sufficient information and detail for an opposing expert to replicate and verify in all respects both the method and results described in the report.”) (quoting Cook v. Rockwell Int’l Corp., 580 F. Supp. 2d 1071, 1121–22 (D. Colo. 2006)). But some courts do not protect an expert’s notes, worksheets, and other preparatory materials unless they are actually part of a “draft” report. See, e.g., In re Application of the Republic of Ecuador, 280 F.R.D. 506, 512–14 (N.D. Cal. 2012); In re Asbestos Prods. Liab. Litig. (No. VI), No. MDL 875, 2011 WL 6181334, at *13 n.11 (E.D. Pa. Dec. 13, 2011); Dongguk Univ. v. Yale Univ., No. 3:08-CV-00441, 2011 WL 1935865, at *1 (D. Conn. May 19, 2011). This view may be short-sighted because characterizing or labeling expert materials as a “draft” report to confer non-discoverable status does not mean the materials are actually part of a “draft” report. Protecting working notes simply because they are contained in a “draft” report elevates form over substance.

The protection for counsel-expert communications raises fewer questions. Under the current rules, these communications are protected except for those involving certain subjects: expert compensation, facts or data provided by counsel that the expert considered in forming the opinions, and assumptions provided by counsel that the expert relied on in forming the opinions. Fed. R. Civ. P. 26(b)(4)(C). Only these portions of counsel-expert communications need to be produced: “[T]he protection applies to all other aspects of the communication beyond the excepted topics.” Fed. R. Civ. P. 26 advisory committee’s note (2010 amend.); see also Innovative Sonic, Ltd. v. Research In Motion, Ltd., No. 3:11-CV-0706-K, 2013 WL 775349, at *3 (N.D. Tex. Mar. 1, 2013). Consequently, counsel and expert should be able to communicate freely without worry that their exchanges will need to be turned over.

Sara Lee Corp. v. Kraft Foods Inc., 273 F.R.D. 416 (N.D. Ill. Apr. 1, 2011), is a leading case on the discoverability of counsel-expert communications after the 2010 amendments. There, the district court ruled that counsel’s communications with the expert were protected from disclosure. The communications involved the expert’s advice on conducting a survey about the particular advertisement involved in the false advertising lawsuit. Because the expert never learned the results of the survey, his methodology and opinions were not affected and the communications did not contain any facts, data, or assumptions that the expert could have considered in assembling his report. The court conceded that the communications would likely have been discoverable prior to the enactment of the 2010 amendments, but the more restrictive expert discovery rules protected the communications from disclosure.

With a better understanding of the current rules regarding expert discovery and some of the open issues, we next consider what the future of expert discovery may hold.


On June 3, 2013, the Standing Committee on Rules of Practice and Procedure approved proposals that may significantly alter the discovery landscape. The Standing Committee has the final opportunity to modify proposed amendments to the federal rules before seeking approval from the Judicial Conference. If the proposed amendments are approved by the Judicial Conference, they are transmitted to the Supreme Court of the United States, and then to Congress. See John D. Bates, Admin. Office of the U.S. Courts, Overview for the Bench, Bar, and Public. If adopted, the proposals could go into effect by December 2015. Id.

One of the proposals is to limit the scope of permissible discovery. Currently, Rule 26(b)(1) permits discovery into “any nonprivileged matter that is relevant to any party’s claim or defense” and, if the court finds good cause, “any matter relevant to the subject matter involved in the action.” “Relevant” here means “reasonably calculated to lead to the discovery of admissible evidence”—an extremely broad standard. Civil Rules Advisory Comm., Draft Minutes, at 14(Nov. 2, 2012)(“[I]n operation many lawyers and judges read the ‘reasonably calculated’ phrase to obliterate all limits on the scope of discovery; any information may lead to other evidence that is relevant and admissible.”). Under the Standing Committee’s current proposal, however, discovery must be “proportional to the needs of the case considering the amount in controversy, the importance of the issues at stake in the action, the parties’ resources, the importance of the discovery in resolving the issues, and whether the burden or expense of the proposed discovery outweighs its likely benefit.” David G. Campbell, Report of the Advisory Committee on Civil Rules 19–22 (May 8, 2013).

What impact would this proposal, if adopted, have on expert discovery? It is possible that there may be little change at all. Much as the heavily anticipated sea change never came to pass when the 2010 amendments were enacted, parties may continue to handle expert discovery in essentially the same way. They may view proportional discovery as already part of the basic discovery rules. Under Rule 26(b)(2)(C)(iii), the court must limit discovery, on its own or by motion, if “the burden or expense of the proposed discovery outweighs its likely benefit, considering the needs of the case, the amount in controversy, the parties’ resources, the importance of the issues at stake in the action, and the importance of the discovery in resolving the issues.” Indeed, the new proposal only seems to move the requirement of proportional discovery from Rule 26(b)(2)(C)(iii) to Rule 26(b)(1).

On the other hand, parties could rely on the proportional discovery standard to limit discovery of experts on matters that go beyond the strict scope of required expert disclosures. Whereas before parties may have issued subpoenas duces tecum to experts or asked deposition questions of experts that cover a broad range of background and methodological issues, parties could choose not to take these actions (and incur the related expense) under the new proposed discovery standard. And courts may agree that the required expert disclosures and depositions covering only those disclosed opinions are all the other side needs to effectively prepare for trial. No longer would a party wish to or even be allowed to subpoena the expert for every single article or book the expert has authored or transcripts of every single deposition or trial in which the expert has given testimony.

Even if no real change occurs on the litigants’ end, change may nonetheless be imposed by the courts. If adopted, the proposed amendments may encourage courts to become more proactive about overseeing discovery, including expert discovery. They may limit the role of experts to a level proportional to the case. This may include, for example, placing limits on expert depositions (number and hours) or foreclosing the ability to submit rebuttal expert reports. By getting involved in the expert discovery process early, a court can confine the issues on which experts are needed or used. But without a clear definition of “proportional” discovery, the courts may be reluctant to set boundaries too narrowly, particularly during discovery when it may not be apparent to the court, or even the litigants, what issues will ultimately be dispositive.

In the end, however, whether the proportional discovery standard would have a material impact on expert discovery is uncertain. Perhaps neither litigants nor the courts will exercise stringent enforcement of this new standard. The proposed changes to the scope of discovery, if adopted, may end up being another overhyped restructuring. As the adage goes, the more things change, the more they stay the same. Despite the changes in the expert discovery rules from yesterday to today and possibly into tomorrow, expert discovery largely remains the same and likely will continue to be the same in the future.

Keywords: litigation, trial practice, proportional discovery, disclosure, draft report, attorney work product

Copyright © 2013, American Bar Association. All rights reserved. This information or any portion thereof may not be copied or disseminated in any form or by any means or downloaded or stored in an electronic database or retrieval system without the express written consent of the American Bar Association. The views expressed in this article are those of the author(s) and do not necessarily reflect the positions or policies of the American Bar Association, the Section of Litigation, this committee, or the employer(s) of the author(s).