7.2Expert Testimony Involving an Ultimate Issue¹

MRE 704 states:

“An opinion is not objectionable just because it embraces an ultimate issue.”

However, an expert witness may not testify to his or her opinion about the defendant’s guilt or the defendant’s state of mind. People v Zitka, 335 Mich App 324, 345-346 (2021). Further, an expert witness is not permitted to “‘testify about the requirements of law which apply to the particular facts in the case or to phrase his opinion in terms of a legal conclusion.’” Id. at 346, quoting People v Drossart, 99 Mich App 66, 75 (1980).

“[O]ur Supreme Court has imposed strict limits on expert testimony that ‘comes too close’ to findings that are left exclusively to the jury.” People v McFarlane, 325 Mich App 507, 521 (2018), quoting People v Peterson, 450 Mich 349, 374 (1995) “For example, in cases involving criminal sexual conduct, an expert may not offer an opinion that the alleged victim had in fact been sexually abused, may not offer testimony that vouches for the victim’s veracity, and may not offer an opinion that the defendant is guilty.” McFarlane, 325 Mich App at 521-522.

In cases involving a child who has sustained injuries unlikely to have been caused by accident, “any use of the word ‘abuse’ in the context of a medical diagnosis, irrespective of whether that is in fact an accepted medical diagnosis, constitutes plain error in a criminal proceeding involving charges of abuse.” People v Ackley (On Remand), 336 Mich App 586, 594 (2021) (case involving child abuse). In Ackley, the defendant’s trial involved medical testimony about injuries sustained by a child who died as a result of injuries allegedly caused by the defendant. Id. at 590. To describe the child’s condition, some expert witnesses used the phrase, “abusive head trauma”—a phrase that uses the word “abusive,” which is “a word forbidden because of its emotional and suggestive connotations[.]” According to the Ackley Court:

“[E]xperts are permitted to draw and testify regarding conclusions that encompass a question to be decided by the jury, so long as the expert does not purport—or, importantly for this matter, even appear to purport—to draw a legal conclusion. Thus, where it is possible to draw a medical diagnosis based on a physical examination, as opposed to a complainant’s self-reporting, an expert is fully permitted to testify that, in their opinion, a particular injury was not accidentally self-inflicted. The expert may not call that manner of injury ‘abuse,’ because, even if that is a term used in the medical community, it is also a legal conclusion and would be understood by laypersons to connote something different from what another doctor might understand.” Ackley, 336 Mich App at 595 (citations omitted).