Mass. R. Evid. 704
An opinion is not objectionable just because it embraces an ultimate issue.
Mass. Guid. Evid. 704
This section is derived from Proposed Mass. R. Evid. 704; Commonwealth v. Woods, 419 Mass. 366, 374-375 (1995); and Simon v. Solomon, 385 Mass. 91, 105 (1982). The critical question is not whether the opinion touches on the ultimate issue, but whether it satisfies Sections 403, Excluding Relevant Evidence for Prejudice, Confusion, Waste of Time, or Other Reasons; 701, Opinion Testimony by Lay Witnesses; 702, Testimony by Expert Witnesses; and any other applicable sections. See Commonwealth v. Goddard, 476 Mass. 443, 446-447 (2017); Commonwealth v. Canty, 466 Mass. 535, 543 (2013); Martel v. Massachusetts Bay Transp. Auth., 403 Mass. 1, 3-4 (1988); Commonwealth v. LaCorte, 373 Mass. 700, 705 (1977); Commonwealth v. Almeida, 34 Mass. App. Ct. 901, 902-903 (1993); Commonwealth v. Lopes, 25 Mass. App. Ct. 988, 990 (1988), citing Commonwealth v. Sendele, 18 Mass. App. Ct. 755, 760 (1984). Accord M.S. Brodin & M. Avery, Massachusetts Evidence § 7.3.2 (2018 ed.).
At least four different, but related, reasons are given for the exclusion of opinion evidence on an ultimate issue. First, such opinions offer no assistance to the fact finders "because the jury are capable of making that assessment without an expert's aid." Commonwealth v. Colin C., 419 Mass. 54, 60 (1994). See Commonwealth v. Andujar, 57 Mass. App. Ct. 529, 531 (2003). Second, "[o]n such questions, the influence of an expert's opinion may threaten the independence of the jury's decision." Simon, 385 Mass. at 105. Third, such questions call for opinions on matters of law or mixed questions of law and fact, and the jury must be allowed to draw their own conclusions from the evidence. See Commonwealth v. Hesketh, 386 Mass. 153, 161-162 (1982). Fourth, expert opinion in the form of conclusions about the credibility of a witness or a party are beyond the scope of the witness's expertise and in the realm of speculation and conjecture. See Commonwealth v. Gardner, 350 Mass. 664, 666 (1966).
Improper Vouching. Expert witness testimony which simply amounts to an opinion on the credibility of a witness is inadmissible as improper vouching; credibility is an issue reserved for the jury that does not require the assistance of an expert. This issue commonly arises in sexual abuse cases, in which an expert witness may testify to general characteristics to assist the jury's understanding, but may not compare the alleged victim to those characteristics. Commonwealth v. Richardson, 423 Mass. 180, 185-186 (1996), quoting Commonwealth v. Trowbridge, 419 Mass. 750, 759 (1995) ("[a]lthough expert testimony on the general behavioral characteristics of sexually abused children is permissible, an expert may not refer or compare the child to those general characteristics"). See Commonwealth v. Jewett, 442 Mass. 356, 368 (2004) ("in the absence of special circumstances, an expert may not be asked whether a rape or sexual assault has occurred"). Testimony about profiling is generally inadmissible. Commonwealth v. Coates, 89 Mass. App. Ct. 728, 733-737 (2016) (trial judge properly excluded criminal-profile testimony that defendant did not fit profile of pedophile); Commonwealth v. Aspen, 85 Mass. App. Ct. 278, 282-284 (2014), citing Commonwealth v. Federico, 425 Mass. 844, 849 (1997) (conviction reversed where expert gave profile testimony relating to intrafamilial sexual abuse that closely resembled complainant's family makeup and dynamic).
Testimony by an expert who has also treated the victim must be carefully scrutinized to avoid the implication that the expert's contact with the victim gives the expert special knowledge about credibility. See Commonwealth v. Quinn, 469 Mass. 641, 646 (2014) (risk of improper vouching was "especially acute" because expert witness had treated victim for months); Trowbridge, 419 Mass. at 759-760. The rule against vouching does not prohibit an expert from explaining physical findings or characteristics and their significance. See, e.g., Commonwealth v. Alvarez, 480 Mass. 299, 314 (2018) (general statements by treating physician that it is "very uncommon" to find physical genital injury in sexual abuse victim and that "absence of physical trauma is not inconsistent with abuse" do not constitute implicit vouching). Cf. Commonwealth v. Burgess, 450 Mass. 422, 436 (2008) ("the prosecutor [improperly] asked [the Commonwealth's expert] to comment on the credibility of the Commonwealth's theory of the case by asking whether its theory was 'consistent' with [the expert's] observations").
Illustrations. For examples of cases applying this section, see M.S. Brodin & M. Avery, Massachusetts Evidence § 7.3 (2018 ed.), and 2 M.G. Perlin & D. Cooper, Proof of Cases in Massachusetts § 71.4 (2017-2018 ed.).
Operating Under the Influence Cases. In Commonwealth v. Canty, 466 Mass. 535, 541 (2013), the court explained that the limitation on testimony that amounts to an opinion as to guilt or innocence applies to the lay witness as well as to the expert witness. Cross-Reference: Section 701, Opinion Testimony by Lay Witnesses.
Opinions About the Law Versus the Facts. Legal questions, as to which testimony is not permitted, should be distinguished from factual conclusions, as to which testimony is proper. The line between a "conclusion of law" and an "ultimate factual issue" is sometimes blurred. Commonwealth v. Little, 453 Mass. 766, 769 (2009) ("Narcotics investigators may testify as experts to describe how drug transactions occur on the street . . . [such as] testimony on the use of lookouts in drug transactions, and the significance of the purity of seized drugs. We have also repeatedly held that there is no error in allowing a police detective to testify that in his opinion the amount of drugs possessed by the defendant was not consistent with personal use but was consistent with an intent to distribute." [Citations and quotations omitted.]). See Commonwealth v. Roderiques, 78 Mass. App. Ct. 515, 522 (2010) (pediatrician allowed to testify that baby's injuries were not accidental); Puopolo v. Honda Motor Co., 41 Mass. App. Ct. 96, 99 (1996) (expert should have been permitted to testify that vehicle was unreasonably dangerous even though special question given to jury was framed in nearly identical language). Cf. Commonwealth v. Brady, 370 Mass. 630, 635 (1976) (insurance agent may not testify to applicability of insurance coverage); Perry v. Medeiros, 369 Mass. 836, 842 (1976) (building inspector cannot give opinion interpreting building code); Commonwealth v. Coleman, 366 Mass. 705, 711 (1975) (medical examiner not permitted to testify that death was "homicide"); DeCanio v. School Comm. of Boston, 358 Mass. 116, 125-126 (1970) (expert could not testify that "suspension and dismissal of probationary teachers without a hearing 'would have no legitimate educational purpose'"); Commonwealth v. Gardner, 350 Mass. 664, 666-667 (1966) (doctor in rape prosecution cannot testify to "forcible entry"); S.D. Shaw & Sons v. Joseph Rugo, Inc., 343 Mass. 635, 639 (1962) (witness may not give opinion as to whether certain work was included in contract specification); Commonwealth v. Ross, 339 Mass. 428, 435 (1959) (guilt); Foley v. Hotel Touraine Co., 326 Mass. 742, 745 (1951) (treasurer of corporation could not testify on question whether assistant manager had "ostensible authority" on day of accident); Silva v. Norfolk & Dedham Mut. Fire Ins. Co., 91 Mass. App. Ct. 413, 420 (2017) (testimony in action brought under G. L. c. 176D that insurer's action was "unfair and deceptive" properly excluded). But see Ford v. Boston Hous. Auth., 55 Mass. App. Ct. 623, 626 (2002) (expert testimony explaining requirements of complicated code was not per se inadmissible; judge had discretion to admit expert opinion of building inspector that "if the door was locked at the time of the accident . . . that would have been noncompliance with the State building code").