Practice Tip: Expert Witness Selection

Historical Development of Expert Witness Discovery Rules

As originally adopted in 1938, the Federal Rules of Civil Procedure did not address expert witness discovery, and early case law often disfavored such discovery in the absence of a showing of extreme need. In fact, in 1946, the advisory committee proposed an amendment to the Federal Rules of Civil Procedure that would have precluded discovery as to the conclusions of most experts. However, as judicial reliance on expert testimony increased, practical considerations led courts to adopt more permissive positions. Consequently, in 1970, the Federal Rules of Civil Procedure were amended specifically to address expert witness discovery. The amendments generally provided for the discovery of “facts known and opinions held” by experts that were “acquired in anticipation of litigation or for trial” and otherwise discoverable, but imposed limitations as to form. Fed. R. Civ. P. 26(b)(4)(A) (1970). In the absence of a court order, expert witness discovery was limited to interrogatories requiring another party to: 1) identify expert witnesses to be called at trial; 2) state the subject matter on which the expert was to testify; 3) state the substance of the facts and opinions to which the expert was expected to testify; and 4) provide a summary of the grounds for each of the expert's opinions. Fed. R. Civ. P. 26(b)(4)(A)(i) (1970). Any further discovery pursuant to court order was subject to court-imposed restrictions as to scope and form. Fed. R. Civ. P. 26(b)(4)(A)(ii) (1970).

The most recent substantive amendments to the Federal Rules of Civil Procedure pertaining to expert witness discovery, promulgated in 1993, stripped away many of the limitations previously imposed on such discovery. Pursuant to the 1993 amendments, parties are required, without awaiting formal discovery requests, to disclose the identity of all expert witnesses, and a written report outlining: 1) all opinions the expert will express and the bases and reasons for them; 2) the data or other information considered by the witness in forming them; 3) any exhibits to be used to support them; 4) the witness' qualifications, including a list of publications authored in the previous ten years; 5) a list of all other cases in which, during the previous four years, the witness testified as an expert at trial or by deposition; and 6) a statement of the compensation to be paid for the study and testimony in the case. Fed. R. Civ. P. 26(a)(2) (1993). Thus, considerably more information than previously available by means of interrogatory is now to be disclosed in the absence of any such request, due not only to the expansion of the types of information to be provided, but also to the change in the scope of the discovery from “facts known” to “data or other information considered.” Compare Fed. R. Civ. P. 26(b)(4)(A)(i) (1970) with Fed. R. Civ. P. 26(a)(2) (1993); see also Karn v. Ingersoll Rand, 168 F.R.D. 633, 655 (N.D. Ind. 1996) (explaining that “considered,” which simply means “to take into account,” clearly invokes a broader spectrum of thought than the phrase “relied upon,” which had been used in prior drafts of the amendments, and which requires dependence on the information). Further, the advisory committee notes explicitly state that parties are not precluded from using traditional discovery methods to obtain information beyond that to be disclosed pursuant to Rule 26(a)(2). Fed. R. Civ. P. 26, 1993 advisory committee notes. The 1993 amendments were intended to promote judicial efficiency, but judicial interpretation of the amendments often frustrates that very purpose.

Judicial Interpretation of Scope of Expert Witness Discovery

Prior to the promulgation of Rule 26(b)(4) of the Federal Rules of Civil Procedure in 1970, courts that allowed expert witness discovery were generally careful to impose restrictions on the scope of such discovery. For example, in the case of E.I. DuPont de Nemours & Co. v. Phillips Petroleum Co., although the court granted a motion to compel expert witness discovery, the court denied several specific requests because the “mere hope that the records might turn up some statements on the part of the scientists which would be inconsistent with some of their conclusions as to [the patent] infringement [was] itself [not] sufficient to constitute good cause for production.” 24 F.R.D. 416, 421-22 (D. Del. 1959).

As noted above, pursuant to the 1970 version of Rule 26, the scope of expert witness discovery supplemental to that available by interrogatory was to be determined by the court. Fed. R. Civ. P. 26(b)(4)(A)(ii) (1970). In the absence of a clearly defined statement as to the scope of expert witness discovery, a variety of approaches emerged. Some courts relied on the same rationales once used to support exceptions to the general rule against expert witness discovery in justifying the scope of discovery permitted. See, e.g., Quadrini v. Sikorsky Aircraft Div., United Aircraft Corp., 74 F.R.D. 594, 595 (D. Conn. 1977) (granting the defendant's motion to compel extensive expert discovery, because “[e]xpert testimony [would] undoubtedly be crucial to the resolution of the complex and technical factual disputes in [the] case, and effective cross-examination [would] be essential”). Other courts evaluated whether the expert had considered or relied upon the information requested in arriving at his opinion. See, e.g., WAIT Radio v. Century Broad. Corp., No. 85 C 07579, 1989 U.S. Dist. LEXIS 12364, at * 12-14 (N.D. Ill. Oct. 12, 1989). Still others allowed expert discovery as to all “materials possessed by an expert and related to the case at hand.” Quaile v. Carol Cable Co., No. 90-7415, 1992 U.S. Dist. LEXIS 15154, at * 5 (E.D. Pa. Oct. 2, 1992) (quoting In re Air Crash Disaster at Stapleton Int'l Airport, 720 F. Supp. 1442, 1444 (D. Colo. 1988)).

Thus, even prior to the 1993 amendments, some courts had begun to allow expert witness discovery beyond the scope of information obtained in anticipation of litigation or for trial. See, e.g., Simon v. G.D. Searle & Co., 119 F.R.D. 680, 680-83 (D. Minn. 1987) (compelling production of all documents relating to a study expert was conducting with funding from defendant including all lab notebooks, data and follow-up forms, medical records, protocols, correspondence with the defendant, checks, and billing, because the expert could not completely exclude the study from the background information and clinical experiences forming the basis for his opinions, and had in fact, based two of his opinions solely on the study).

Since the adoption of the 1993 amendments, courts have defined the scope of expert witness discovery more broadly. For example, in Western Resources, Inc. v. Union Pacific Railroad, Co., the court rejected the plaintiff's expert's argument that the defendant's discovery requests were not relevant because the expert had not considered or relied on the information and/or documents requested ' documents relating to consulting work the expert had done ' in drafting his report. No. 00-2043, 2002 U.S. Dist. LEXIS 14797, at * 8-10 (D. Kan. July 23, 2002). In so doing, the court made three observations. First, the plain language of Rule 26 does not suggest the scope of expert discovery is limited to that of the mandatory disclosures outlined in Rule 26(a)(2). Id. at * 9-10. Second, the 1993 advisory committee notes explicitly state that parties are not precluded from using traditional discovery methods to obtain information beyond that to be disclosed pursuant to Rule 26(a)(2). Id. Third, the
“[d]iscovery of all material possessed by an expert relating to the matter at hand develops a record which prevents a sanitized presentation at trial, purged of less favorable opinions expressed at an earlier date.” Id. at * 10. Based on these observations, the court held that the scope of expert witness discovery is defined under Rule 26(b)(1), which provides as follows: “[P]arties may obtain discovery regarding any matter, not privileged, that is relevant to the claim or defense of any party.” Id. at * 9 (quoting Fed. R. Civ. P. 26(b)(1)). This reading of the rule is inconsistent with pre-1993 case law that expressly states that Rule 26(b)(1) is inapposite as to expert witness discovery. See Quadrini, 74 F.R.D. at 595. It is also inconsistent with the history of the rules as to expert witness discovery, and the prior structure of Rule 26. Nonetheless, other courts have similarly held that the scope of expert witness discovery supplemental to the mandatory disclosures outlined in Rule 26(a) is controlled by Rule 26(b)(1). See, e.g., USGen New England, Inc. v. TransCanada Pipelines, Ltd. (In re USGen New England, Inc.) No. 03, 2007 Bankr. LEXIS 2820, at * 23-24 (Bankr. D. Md. Aug. 16, 2007); Moses v. Halstead, 236 F.R.D. 667, 677 (D. Kan. 2006); Mizerak v. Wal-Mart Stores, Inc., No. 00-CV-5875, 2002 U.S. Dist. LEXIS 12156, at * 4 (E.D. Pa. Jan. 22, 2002).

Federal and State Court Decisions

Disputes over expert witness discovery typically arise from requests for an expert's data and other information considered by an expert, tax returns or other financial information, and the medical records of other patients. These disputes usually turn on the factual circumstances from which the dispute arises; however, as the federal and state case law discussed below illustrates, the following are often central to courts' determinations: 1) whether the information is relevant in providing a foundation for cross-examination; 2) whether the information is relevant in demonstrating an expert's bias; 3) non-party privacy and privilege concerns; 4) the expert's burden and expense in accommodating the request; and 5) whether the information sought is available through other less invasive and burdensome means.

The first category of requests, those for data and other information considered by an expert in arriving at his or her opinion, is particularly difficult to oppose for two reasons. First, where an expert's research interests and testimony overlap, as is generally the case, it is difficult to argue that the expert did not consider the information in arriving at his opinion. Second, underlying data and research are central to both the Daubert inquiry as to reliability and cross-examination. Thus, decisions such as that in Buxbaum v. Board Of Trustees of Indiana University, a case in which the court granted the defendant's motion to compel the production of data from tests the expert performed in prior unrelated litigation, are not surprising. No. CDV-2000-31, 2002 Mont. Dist. LEXIS 2018, at * 5 (Mont. Dist. Ct. May 29, 2002). Nonetheless, courts have refused to compel discovery of information considered by an expert in arriving at his or her opinion, in instances where doing so would impose an undue burden on the expert. For example, in Dering v. ServiceExperts Alliance LLC, the court held that a defense valuation expert need not disclose lost profit reports prepared for other clients, sought for the purpose of determining whether the expert had used the same method of calculating lost profits in each instance, because the significant burden placed on the expert, his firm and their clients outweighed the probative value of the requested reports. Civ. No. 1:06-CV-00357, 2007 U.S. Dist. LEXIS 89972, at * 1-9 (N.D. Ga. Dec. 6, 2007).

Tax returns, income records and other financial information are also often sought in discovery to probe an expert witness' potential biases. Although information on the compensation and rates of an expert witness is typically discoverable, courts tend to disfavor disclosure of an expert's total income or personal income tax returns. For example, in Ex parte Morris, the court held that two experts were not required to produce federal and state income tax returns for each of the previous nine years, noting that the probative value of such records was substantially outweighed by the prejudice to the experts associated with disclosure, especially given that counsel had already obtained information concerning the experts' rates, the states in which they had testified, the number of depositions given as experts and the approximate percentage of income received for medical-legal cases. 530 So. 2d 785, 787-88 (Ala. 1988).

Likewise, in Mejia v. Reynolds Fence & Guardrail, the court granted the defendant's motion to quash a subpoena for an expert's business and personal income tax returns, noting that the disclosure of W2 and 1099 tax records related to consulting work performed on behalf of liability insurance carriers, pursuant to the court's order, would sufficiently demonstrate any existing links between the expert and the insurance carriers. Civ. No. 4:06-cv-01480, 2007 U.S. Dist. LEXIS 65610, at * 1-3 (D.S.C. Sept. 5, 2007).

Not surprisingly, courts tend to be most hesitant about granting discovery requests seeking medical expert witnesses' records regarding other patients. For example, in Wozniak v. Kombrink, the appellate court reversed the trial court's decision requiring the production of an expert's records of independent medical examinations and second opinions performed at the request of insurance companies, reasoning that even if names and personal data could be deleted from the medical records in question, the court was unwilling to risk the “rights of privacy and protection of confidential information” for the purpose of impeaching an expert witness, especially since less risky methods of discovery, including interrogatories, were available. No. C-890531, 1991 Ohio App. LEXIS 606, at * 6, 12-13 (Ohio Ct. App. Feb. 13, 1991). Similarly, in In re Plains Marketing, L.P., the court held an expert need not produce medical evaluations stemming from unrelated litigation over the past ten years, finding that a request for possibly confidential medical information, compliance with which would demand considerable time and expense from the expert, extended beyond the limits of allowable pre-trial discovery. 195 S.W.3d 780, 782-84 (Tex. App. 2006). Where medical records are sought not for the purposes of showing bias, but rather because the expert's personal experience with a particular procedure or condition forms the basis for his opinion, courts, however will be more likely to require the production of redacted materials, due to the probative nature of the requested information. See, e.g., In re Orthopedic Bone Screw Prods. Liab. Litig., 1996 WL 900345, at * 1-5.

Practical Advice for Managing Expert Witness Discovery

Lengthy expert witness discovery disputes are generally not in the best interest of clients, as they are costly, and may leave one without an expert after deadlines for disclosure have passed. This being the case, when interviewing potential expert witnesses, one would be well served to inquire as to information or materials in the expert's control or possession that might be relevant to the parties' claims and defenses or bias, and as to the expert's comfort with discovery of such information or materials. Preliminary research as to controlling law on the issue of expert discovery is also advisable, particularly when litigating in state court, where the rules may provide greater protection from expert witness discovery. With advance knowledge of a potential discovery issue, it may be possible to enter into a stipulation regarding the scope of discovery, such as those entered into in respect of attorney work-product provided to expert witnesses. In appropriate cases, counsel also may consider designating a “back-up” expert, to avoid being left without a witness on a critical issue, in the event that the first retained expert decides to withdraw. Moreover, knowledge of potential discovery issues may counsel against retaining a specific expert ' even if, and in some cases precisely because, the expert has made research into a matter at issue in the case his or her life work.

James H. Rotondo, a member of this newsletter's Board of Editors, is a Partner in Day Pitney LLP's Hartford, CT, office. He represents a broad range of corporate clients in product liability, negligence, insurance coverage, and commercial litigation matters. Andrea E. K. Thomas is a member of the firm's commercial litigation group in the same office. Her practice focuses on product liability and insurance coverage disputes.

Experts were once generally protected from discovery. Today, however, with ever-increasing reliance on expert witness testimony, discovery has become a high-stakes endeavor. While the Daubert pre-requisites for admissibility counsel in favor of retaining the foremost expert on a particular issue ' an individual who has made the issue his or her life work ' practical considerations as to expert witness discovery may counsel otherwise. As with parties to litigation, experts are generally annoyed by invasive discovery requests. Experts, however, have a far more limited interest in a case than the parties. If discovery requests threaten professional reputation, or even just become irritating or burdensome, an expert may choose the path of least resistance, abandoning the case, and leaving both counsel and client in the lurch.

Introduction

As one court has suggested, “Paradoxically, the greater the reach of an expert's opinion and depth of the support that is proffered to justify it, the greater the burden [may be] that follows concerning the data and information that has been relied upon to make the opinion more persuasive than it might otherwise be.” See In re Orthopedic Bone Screw Prods. Liab. Litig., No. MDL 1014, 1996 WL 900345, at * 3 (E.D. Pa. July 16, 1996). Nevertheless, courts are not blind to the consequences of allowing far-reaching expert witness discovery. As the court noted in Elkins v. Syken:

[D]iscovery was never intended to be used as a tactical tool to harass an adversary in a manner that actually chills the availability of information on non-party witnesses, nor was it intended to make the discovery process so expensive that it could effectively deny access to information and witnesses or force parties to resolve their disputes unjustly ' To [allow unfettered expert witness discovery] could have a chilling effect on the ability to obtain [experts] willing to testify and could cause future trials to consist of many days of questioning on the collateral issue of expert bias rather than on the true issues of liability and damages. 672 So. 2d 517, 522 (Fla. 1996).

This article briefly outlines the historical development of the federal rules relating to expert witness discovery, discusses evolving judicial interpretations of the scope of expert witness discovery, provides a sampling of federal and state court rulings as to various types of expert witness discovery requests, and offers practical advice in respect to managing expert witness discovery.

Historical Development of Expert Witness Discovery Rules

As originally adopted in 1938, the Federal Rules of Civil Procedure did not address expert witness discovery, and early case law often disfavored such discovery in the absence of a showing of extreme need. In fact, in 1946, the advisory committee proposed an amendment to the Federal Rules of Civil Procedure that would have precluded discovery as to the conclusions of most experts. However, as judicial reliance on expert testimony increased, practical considerations led courts to adopt more permissive positions. Consequently, in 1970, the Federal Rules of Civil Procedure were amended specifically to address expert witness discovery. The amendments generally provided for the discovery of “facts known and opinions held” by experts that were “acquired in anticipation of litigation or for trial” and otherwise discoverable, but imposed limitations as to form. Fed. R. Civ. P. 26(b)(4)(A) (1970). In the absence of a court order, expert witness discovery was limited to interrogatories requiring another party to: 1) identify expert witnesses to be called at trial; 2) state the subject matter on which the expert was to testify; 3) state the substance of the facts and opinions to which the expert was expected to testify; and 4) provide a summary of the grounds for each of the expert's opinions. Fed. R. Civ. P. 26(b)(4)(A)(i) (1970). Any further discovery pursuant to court order was subject to court-imposed restrictions as to scope and form. Fed. R. Civ. P. 26(b)(4)(A)(ii) (1970).

The most recent substantive amendments to the Federal Rules of Civil Procedure pertaining to expert witness discovery, promulgated in 1993, stripped away many of the limitations previously imposed on such discovery. Pursuant to the 1993 amendments, parties are required, without awaiting formal discovery requests, to disclose the identity of all expert witnesses, and a written report outlining: 1) all opinions the expert will express and the bases and reasons for them; 2) the data or other information considered by the witness in forming them; 3) any exhibits to be used to support them; 4) the witness' qualifications, including a list of publications authored in the previous ten years; 5) a list of all other cases in which, during the previous four years, the witness testified as an expert at trial or by deposition; and 6) a statement of the compensation to be paid for the study and testimony in the case. Fed. R. Civ. P. 26(a)(2) (1993). Thus, considerably more information than previously available by means of interrogatory is now to be disclosed in the absence of any such request, due not only to the expansion of the types of information to be provided, but also to the change in the scope of the discovery from “facts known” to “data or other information considered.” Compare Fed. R. Civ. P. 26(b)(4)(A)(i) (1970) with Fed. R. Civ. P. 26(a)(2) (1993); see also Karn v. Ingersoll Rand , 168 F.R.D. 633, 655 (N.D. Ind. 1996) (explaining that “considered,” which simply means “to take into account,” clearly invokes a broader spectrum of thought than the phrase “relied upon,” which had been used in prior drafts of the amendments, and which requires dependence on the information). Further, the advisory committee notes explicitly state that parties are not precluded from using traditional discovery methods to obtain information beyond that to be disclosed pursuant to Rule 26(a)(2). Fed. R. Civ. P. 26, 1993 advisory committee notes. The 1993 amendments were intended to promote judicial efficiency, but judicial interpretation of the amendments often frustrates that very purpose.

Judicial Interpretation of Scope of Expert Witness Discovery

Prior to the promulgation of Rule 26(b)(4) of the Federal Rules of Civil Procedure in 1970, courts that allowed expert witness discovery were generally careful to impose restrictions on the scope of such discovery. For example, in the case of E.I. DuPont de Nemours & Co. v. Phillips Petroleum Co., although the court granted a motion to compel expert witness discovery, the court denied several specific requests because the “mere hope that the records might turn up some statements on the part of the scientists which would be inconsistent with some of their conclusions as to [the patent] infringement [was] itself [not] sufficient to constitute good cause for production.” 24 F.R.D. 416, 421-22 (D. Del. 1959).

As noted above, pursuant to the 1970 version of Rule 26, the scope of expert witness discovery supplemental to that available by interrogatory was to be determined by the court. Fed. R. Civ. P. 26(b)(4)(A)(ii) (1970). In the absence of a clearly defined statement as to the scope of expert witness discovery, a variety of approaches emerged. Some courts relied on the same rationales once used to support exceptions to the general rule against expert witness discovery in justifying the scope of discovery permitted. See, e.g., Quadrini v. Sikorsky Aircraft Div., United Aircraft Corp. , 74 F.R.D. 594, 595 (D. Conn. 1977) (granting the defendant's motion to compel extensive expert discovery, because “[e]xpert testimony [would] undoubtedly be crucial to the resolution of the complex and technical factual disputes in [the] case, and effective cross-examination [would] be essential”). Other courts evaluated whether the expert had considered or relied upon the information requested in arriving at his opinion. See, e.g., WAIT Radio v. Century Broad. Corp. , No. 85 C 07579, 1989 U.S. Dist. LEXIS 12364, at * 12-14 (N.D. Ill. Oct. 12, 1989). Still others allowed expert discovery as to all “materials possessed by an expert and related to the case at hand.” Quaile v. Carol Cable Co., No. 90-7415, 1992 U.S. Dist. LEXIS 15154, at * 5 (E.D. Pa. Oct. 2, 1992) (quoting In re Air Crash Disaster at Stapleton Int'l Airport, 720 F. Supp. 1442, 1444 (D. Colo. 1988)).

Thus, even prior to the 1993 amendments, some courts had begun to allow expert witness discovery beyond the scope of information obtained in anticipation of litigation or for trial. See, e.g., Simon v. G.D. Searle & Co. , 119 F.R.D. 680, 680-83 (D. Minn. 1987) (compelling production of all documents relating to a study expert was conducting with funding from defendant including all lab notebooks, data and follow-up forms, medical records, protocols, correspondence with the defendant, checks, and billing, because the expert could not completely exclude the study from the background information and clinical experiences forming the basis for his opinions, and had in fact, based two of his opinions solely on the study).

Since the adoption of the 1993 amendments, courts have defined the scope of expert witness discovery more broadly. For example, in Western Resources, Inc. v. Union Pacific Railroad, Co., the court rejected the plaintiff's expert's argument that the defendant's discovery requests were not relevant because the expert had not considered or relied on the information and/or documents requested ' documents relating to consulting work the expert had done ' in drafting his report. No. 00-2043, 2002 U.S. Dist. LEXIS 14797, at * 8-10 (D. Kan. July 23, 2002). In so doing, the court made three observations. First, the plain language of Rule 26 does not suggest the scope of expert discovery is limited to that of the mandatory disclosures outlined in Rule 26(a)(2). Id. at * 9-10. Second, the 1993 advisory committee notes explicitly state that parties are not precluded from using traditional discovery methods to obtain information beyond that to be disclosed pursuant to Rule 26(a)(2). Id. Third, the
“[d]iscovery of all material possessed by an expert relating to the matter at hand develops a record which prevents a sanitized presentation at trial, purged of less favorable opinions expressed at an earlier date.” Id. at * 10. Based on these observations, the court held that the scope of expert witness discovery is defined under Rule 26(b)(1), which provides as follows: “[P]arties may obtain discovery regarding any matter, not privileged, that is relevant to the claim or defense of any party.” Id. at * 9 (quoting Fed. R. Civ. P. 26(b)(1)). This reading of the rule is inconsistent with pre-1993 case law that expressly states that Rule 26(b)(1) is inapposite as to expert witness discovery. See Quadrini, 74 F.R.D. at 595. It is also inconsistent with the history of the rules as to expert witness discovery, and the prior structure of Rule 26. Nonetheless, other courts have similarly held that the scope of expert witness discovery supplemental to the mandatory disclosures outlined in Rule 26(a) is controlled by Rule 26(b)(1). See, e.g., USGen New England, Inc. v. TransCanada Pipelines, Ltd. (In re USGen New England, Inc.) No. 03, 2007 Bankr. LEXIS 2820, at * 23-24 (Bankr. D. Md. Aug. 16, 2007); Moses v. Halstead , 236 F.R.D. 667, 677 (D. Kan. 2006); Mizerak v. Wal-Mart Stores, Inc., No. 00-CV-5875, 2002 U.S. Dist. LEXIS 12156, at * 4 (E.D. Pa. Jan. 22, 2002).

Federal and State Court Decisions

Disputes over expert witness discovery typically arise from requests for an expert's data and other information considered by an expert, tax returns or other financial information, and the medical records of other patients. These disputes usually turn on the factual circumstances from which the dispute arises; however, as the federal and state case law discussed below illustrates, the following are often central to courts' determinations: 1) whether the information is relevant in providing a foundation for cross-examination; 2) whether the information is relevant in demonstrating an expert's bias; 3) non-party privacy and privilege concerns; 4) the expert's burden and expense in accommodating the request; and 5) whether the information sought is available through other less invasive and burdensome means.

The first category of requests, those for data and other information considered by an expert in arriving at his or her opinion, is particularly difficult to oppose for two reasons. First, where an expert's research interests and testimony overlap, as is generally the case, it is difficult to argue that the expert did not consider the information in arriving at his opinion. Second, underlying data and research are central to both the Daubert inquiry as to reliability and cross-examination. Thus, decisions such as that in Buxbaum v. Board Of Trustees of Indiana University, a case in which the court granted the defendant's motion to compel the production of data from tests the expert performed in prior unrelated litigation, are not surprising. No. CDV-2000-31, 2002 Mont. Dist. LEXIS 2018, at * 5 (Mont. Dist. Ct. May 29, 2002). Nonetheless, courts have refused to compel discovery of information considered by an expert in arriving at his or her opinion, in instances where doing so would impose an undue burden on the expert. For example, in Dering v. ServiceExperts Alliance LLC, the court held that a defense valuation expert need not disclose lost profit reports prepared for other clients, sought for the purpose of determining whether the expert had used the same method of calculating lost profits in each instance, because the significant burden placed on the expert, his firm and their clients outweighed the probative value of the requested reports. Civ. No. 1:06-CV-00357, 2007 U.S. Dist. LEXIS 89972, at * 1-9 (N.D. Ga. Dec. 6, 2007).

Tax returns, income records and other financial information are also often sought in discovery to probe an expert witness' potential biases. Although information on the compensation and rates of an expert witness is typically discoverable, courts tend to disfavor disclosure of an expert's total income or personal income tax returns. For example, in Ex parte Morris, the court held that two experts were not required to produce federal and state income tax returns for each of the previous nine years, noting that the probative value of such records was substantially outweighed by the prejudice to the experts associated with disclosure, especially given that counsel had already obtained information concerning the experts' rates, the states in which they had testified, the number of depositions given as experts and the approximate percentage of income received for medical-legal cases. 530 So. 2d 785, 787-88 (Ala. 1988).

Likewise, in Mejia v. Reynolds Fence & Guardrail, the court granted the defendant's motion to quash a subpoena for an expert's business and personal income tax returns, noting that the disclosure of W2 and 1099 tax records related to consulting work performed on behalf of liability insurance carriers, pursuant to the court's order, would sufficiently demonstrate any existing links between the expert and the insurance carriers. Civ. No. 4:06-cv-01480, 2007 U.S. Dist. LEXIS 65610, at * 1-3 (D.S.C. Sept. 5, 2007).

Not surprisingly, courts tend to be most hesitant about granting discovery requests seeking medical expert witnesses' records regarding other patients. For example, in Wozniak v. Kombrink, the appellate court reversed the trial court's decision requiring the production of an expert's records of independent medical examinations and second opinions performed at the request of insurance companies, reasoning that even if names and personal data could be deleted from the medical records in question, the court was unwilling to risk the “rights of privacy and protection of confidential information” for the purpose of impeaching an expert witness, especially since less risky methods of discovery, including interrogatories, were available. No. C-890531, 1991 Ohio App. LEXIS 606, at * 6, 12-13 (Ohio Ct. App. Feb. 13, 1991). Similarly, in In re Plains Marketing, L.P., the court held an expert need not produce medical evaluations stemming from unrelated litigation over the past ten years, finding that a request for possibly confidential medical information, compliance with which would demand considerable time and expense from the expert, extended beyond the limits of allowable pre-trial discovery. 195 S.W.3d 780, 782-84 (Tex. App. 2006). Where medical records are sought not for the purposes of showing bias, but rather because the expert's personal experience with a particular procedure or condition forms the basis for his opinion, courts, however will be more likely to require the production of redacted materials, due to the probative nature of the requested information. See, e.g., In re Orthopedic Bone Screw Prods. Liab. Litig., 1996 WL 900345, at * 1-5.

Practical Advice for Managing Expert Witness Discovery

Lengthy expert witness discovery disputes are generally not in the best interest of clients, as they are costly, and may leave one without an expert after deadlines for disclosure have passed. This being the case, when interviewing potential expert witnesses, one would be well served to inquire as to information or materials in the expert's control or possession that might be relevant to the parties' claims and defenses or bias, and as to the expert's comfort with discovery of such information or materials. Preliminary research as to controlling law on the issue of expert discovery is also advisable, particularly when litigating in state court, where the rules may provide greater protection from expert witness discovery. With advance knowledge of a potential discovery issue, it may be possible to enter into a stipulation regarding the scope of discovery, such as those entered into in respect of attorney work-product provided to expert witnesses. In appropriate cases, counsel also may consider designating a “back-up” expert, to avoid being left without a witness on a critical issue, in the event that the first retained expert decides to withdraw. Moreover, knowledge of potential discovery issues may counsel against retaining a specific expert ' even if, and in some cases precisely because, the expert has made research into a matter at issue in the case his or her life work.

James H. Rotondo, a member of this newsletter's Board of Editors, is a Partner in Day Pitney LLP's Hartford, CT, office. He represents a broad range of corporate clients in product liability, negligence, insurance coverage, and commercial litigation matters. Andrea E. K. Thomas is a member of the firm's commercial litigation group in the same office. Her practice focuses on product liability and insurance coverage disputes.