A.Witness Lists
“Witness lists are an element of discovery.” Grubor Enterprises, Inc v Kortidis, 201 Mich App 625, 628 (1993). They serve the purpose of avoiding “‘trial by surprise.’” Id., quoting Stepp v Dep’t of Nat Resources, 157 Mich App 774, 779 (1987).
The parties must file and serve their witness lists within the time limits prescribed by the court under MCR 2.401(B)(2)(a). MCR 2.401(I)(1). The witness list should include the witness’s name, address (if known), whether the witness is an expert, and his or her field of expertise. MCR 2.401(I)(1)(a)-(b). However, only a general identification is necessary if the witness is a records custodian “whose testimony would be limited to providing the foundation for the admission of records[.]” MCR 2.401(I)(1)(a).
B.Sanctions for Failure to File Witness List
“The court may order that any witness not listed in accordance with [MCR 2.401] will be prohibited from testifying at trial except upon good cause shown.” MCR 2.401(I)(2). “While it is within the trial court’s authority to bar an expert witness or dismiss an action as a sanction for the failure to timely file a witness list, the fact that such action is discretionary rather than mandatory necessitates a consideration of the circumstances of each case to determine if such a drastic sanction is appropriate.” Dean v Tucker, 182 Mich App 27, 32 (1990). Just because a witness list was not timely filed does not justify the imposition of such a sanction. Id. at 32. “Unlike MCR 2.401(I)(2), which allows the court to prohibit a witness from testifying if they are not listed in accordance with the court rule, MCR 2.313(B), which addresses the failure to comply with orders compelling disclosure or discovery, expressly lists a host of varying sanctions that the court may consider.” Smith v Beaumont Health, ___ Mich ___, ___ (2026). See Section 5.1(J) for additional discussion of the Dean case and a nonexhaustive list of factors to consider when determining what is an appropriate sanction.
Motion to amend witness list. A trial court ruling on a motion to amend a witness list is not required to consider each of the Dean factors; while those factors “could be relevant, the primary considerations for a trial court in assessing such a motion are (1) the diligence of the moving party and (2) the prejudice that either side would incur from granting or denying the motion.” Smith, ___ Mich at ___. MCR 2.401(I)(2) “properly focuses the trial court’s attention on the adequacy of the party’s explanation of ‘good cause’ along with a ‘showing’ that the party’s conduct supports this explanation, such as diligent efforts to mitigate prejudice to the other parties.” Smith, ___ Mich at ___. “Good cause is a satisfactory, sound or valid reason.” Id. at ___ (quotation marks and citation omitted).
Considerations bearing on the moving party’s diligence “include the timeliness of a party’s motion to amend its witness list after discovering the unavailability of a witness; the absence of repeated previous delays; whether the discovery period has concluded; the effect on mediation (i.e., case evaluation); and whether the party was made aware of a need to obtain another witness.” Id. at ___. “In terms of prejudice, the lack of diligence itself may be prejudicial to the opposing party because of the increased costs of unnecessary litigation, for example, when the originally proposed expert witness has already been deposed, or . . . when a substitute expert provides a different theory of the case, i.e., trial by surprise.” Id. at ___. Further, “whether the party making the request may be prejudiced by denial of the motion is also relevant in assessing whether there is ‘good cause’ to grant a motion to amend.” Id. at ___ (concluding that the circuit court’s denial of the motion was flawed where its opinion “provide[d] scant discussion of plaintiff’s diligence in securing an expert witness and fail[ed] to articulate any prejudice to defendants, particularly given that the court mistakenly believed that the discovery period had closed . . . when the court had, in fact, extended discovery”).
C.Standard of Review
A court’s decision to permit or exclude undisclosed witnesses is reviewed for an abuse of discretion. Kalamazoo Oil Co v Boerman, 242 Mich App 75, 90-91 (2000).