Model Rules of Professional Conduct Rule 3.7 contains the well-known prohibition on lawyer testimony known as the "Lawyer as Witness Rule" or the "Attorney Testimony Rule." It provides:
(a) A lawyer shall not act as advocate at a trial in which the lawyer is likely to be a necessary witness unless:
(1) the testimony relates to an uncontested issue;
(2) the testimony relates to the nature and value of legal services rendered in the case; or
(3) disqualification of the lawyer would work substantial hardship on the client.
(b) A lawyer may act as advocate in a trial in which another lawyer in the lawyer's firm is likely to be called as a witness unless precluded from doing so by Rule 1.7 or Rule 1.9.
Ann. Model Rules of Prof'l Conduct R. 3.7 ("Lawyer as Witness").
Every state has adopted some version of the Attorney Testimony Rule. See ABA/CPR Policy Implementation Committee, Rule 3.7: Lawyer as Witness, http://www.americanbar.org/content/dam/aba/administrative/professional_responsibility/mrpc_3_7.authcheckdam.pdf (last visited Oct. 16, 2016).
Comment 1 to Model Rule 3.7 explains that the rule is necessary because "[c]ombining the roles of advocate and witness can prejudice the tribunal and the opposing party and can also involve a conflict of interest between the lawyer and client." Ann. Model Rules of Prof'l Conduct R. 3.7 cmt. 1. In particular, "[t]he tribunal has proper objection when the trier of fact may be confused or misled by a lawyer serving as both advocate and witness," and the opposing party has such an objection "where the combination of roles may prejudice that party's rights in the litigation." Id. § 3.7 cmt. 2. Courts have expressed particular concern that taking an oath as a witness may improperly enhance (or detract from) the credibility of the lawyer as an advocate. Bottaro v. Hatton Assocs., 680 F.2d 895, 897 (2d Cir. 1982); Gen. Mill Supply Co. v. SCA Servs., Inc., 697 F.2d 704, 712 (6th Cir. 1982).
Many courts have recognized that "the only justification for the attorney testimony rule that might be viewed as affecting the rights of the opposing party is that derived from the fear that the jury will either accord such testimony undue weight, or will be unable to distinguish between the attorney's testimony, offered under oath, and his legal argument, offered in rhetorical support of his client's case." Crowe v. Smith, 151 F.3d 217, 233-34 (5th Cir. 1998); People v. Superior Ct. of San Luis Obispo County, 84 Cal. App. 3d 491, 501, 148 Cal. Rptr. 704 (1978).
As a result, the rule is generally deemed inapplicable where the testimony is made to a judge, as opposed to a jury. Greenebaum-Mtn. Mortg. Co. v. Pioneer Nat'l Title Ins. Co., 421 F. Supp. 1348, 1354 (D. Col. 1976). Similarly, in most jurisdictions the rule has been deemed to apply only to the actual trial, and not to pretrial proceedings, including motions practice. See, e.g., Merrill Lynch Bus. Fin. Servs., Inc. v. Nudell, 239 F. Supp. 2d 1170, 1174 (D. Colo. 2003) (Rule 3.7 does not automatically require disqualification from pretrial activities such as "participating in strategy sessions, pretrial hearings, settlement conferences, or motions practice"). But see Lowe v. Experian, 328 F. Supp. 2d 1122, 1127 (D. Kan. 2004) (disqualification not required for pretrial activities but may be required if activities involve "obtaining evidence which, if admitted at trial, would reveal the attorney's dual role").
The question thus arises regarding the extent to which an attorney may "testify" in an affidavit or declaration relating to a motion for summary judgment. It is well established that an attorney's affidavit can be used, in connection with a summary judgment motion, for the simple purpose of placing documents produced in discovery before the court. See, e.g., United States v. Letscher, 83 F. Supp. 2d 367, 381 (S.D.N.Y. 1999) ("[I]t is usual for counsel to put documents before the Court on summary judgment motions as enclosures to counsel's affidavit."); Bank One Lima, N.A. v. Altenburger, 84 Ohio App. 3d 250, 253, 616 N.E.2d 954, 955 (1992) (attorney did not violate the attorney testimony rule by submitting affidavit stating only that documents attached to it were received by him from opposing counsel, and identifying expert witnesses).
At least one scholar has argued that it is never appropriate to apply the attorney testimony rule to an affidavit relating to summary judgment. Douglas R. Richmond, Lawyers as Witnesses, 36 N.M. L. Rev. 47, 50 (Winter 2006) ("In addition to its clear language, there is no policy reason commending the rule's application to lawyers' affidavit testimony at summary judgment. Because it is the judge who reads motions, there is no chance that the lawyer's dual roles will be confusing. It is equally unlikely that a judge, as compared to a jury, will be unfairly influenced by the lawyer's dual roles.").
Some courts have held that the attorney testimony rule applies to affidavits as well as testimony at trial. See Int'l Res. Ventures, Inc. v. Diamond Mining Co. of Am., 326 Ark. 765, 769, 934 S.W.2d 218, 220 (1996). However, in general, courts appear to be reluctant to disqualify an attorney for violating the attorney testimony rule solely on the basis of statements made in an affidavit in support of summary judgment, even where the attorney's statements go far beyond merely putting documents before the court. In Zurich Insurance Co. v. Knotts, 52 S.W.3d 555, 557 (Ky. 2001), as amended (Aug. 29, 2001), the plaintiffs' attorney filed a personal affidavit in opposition to the defendants' motion for summary judgment, in which he referred to the parties' settlement negotiations and stated that based upon his observations as primary negotiator for the plaintiffs, there were genuine issues of material fact precluding summary judgment. The defendants moved to disqualify the attorney on the grounds that he made himself a necessary witness by filing his personal affidavit. Id. The trial court granted the motion, but the Kentucky Court of Appeals and the Supreme Court reversed, noting that the parties had specified that the attorney would not be called at trial to testify on behalf of his clients, and that in fact, he had no information that was crucial to their claims. Id. at 560. The court further noted that there had been no evidence that "the information contained in [the attorney's affidavit was] unavailable from other sources" or that his testimony would conflict with that of other witnesses. Id. Most importantly, the court determined that the attorney's disqualification would inflict substantial hardship on the plaintiffs. Id.
All this said, the fact that an attorney is unlikely to be disqualified under the attorney testimony rule for making factual assertions in an affidavit does not mean that the attorney can use the summary judgment procedure to make an "end run" around the rule, obtaining summary judgment on the basis of attorney testimony when it would not be possible to rely on that testimony at trial. To meet its burden of production on a motion for summary judgment, a party must produce evidence that would be admissible at trial. Therefore, courts will generally decline to consider portions of attorney affidavits or declarations that would be inadmissible at trial. See In re Boardwalk Dev. Co., 72 B.R. 152, 155-56 (Bankr. E.D.N.C. 1987); Curran v. Aetna Life Ins. Co., No. 13-CV-00289 (NSR), 2016 WL 3843085, at *8 (S.D.N.Y. July 11, 2016) (on cross-motions for summary judgment, court disregarded legal arguments and factual averments made in counsel's declaration).