The facts or data in the particular case upon which an expert witness bases an opinion or inference may be those perceived by or made known to the witness at or before the hearing. These include (a) facts observed by the witness or otherwise in the witness’s direct personal knowledge; (b) evidence already in the record or that will be presented during the course of the proceedings, which facts may be assumed to be true in questions put to the witness; and (c) facts or data not in evidence if the facts or data are independently admissible in evidence and are a permissible basis for an expert to consider in formulating an opinion.
This section is derived from Department of Youth Servs. v. A Juvenile, 398 Mass. 516, 531, 499 N.E.2d 812, 820–821 (1986); LaClair v. Silberline Mfg. Co., 379 Mass. 21, 32, 393 N.E.2d 867, 874 (1979); and Commonwealth v. Russ, 232 Mass. 58, 73, 122 N.E. 176, 182 (1919). Massachusetts has not fully adopted Fed. R. Evid. 703, or Proposed Mass. R. Evid. 703, which would permit opinions based on inadmissible evidence if it is of a type reasonably relied upon by experts in the relevant field.
“When an expert provides the jury with an opinion regarding the facts of the case, that opinion must rest on a proper basis, else inadmissible evidence might enter in the guise of expert opinion. The expert must have knowledge of the particular facts from firsthand observation, or from a proper hypothetical question posed by counsel, or from unadmitted evidence that would nevertheless be admissible.”
Commonwealth v. Waite, 422 Mass. 792, 803, 665 N.E.2d 982, 990 (1996). See id. at 803–804, 665 N.E.2d at 990–991 (psychologist called by the defense in a murder trial could opine on the defendant’s mental impairment at the time of the offense based on the witness’s interview with the defendant five weeks after the killings, and the contents of police and medical records, but not on the basis of a psychiatrist’s earlier “preliminary diagnosis” that was not shown to be reliable and independently admissible). Accord Vassallo v. Baxter Healthcare Corp., 428 Mass. 1, 15–16, 696 N.E.2d 909, 919 (1998) (“The judge properly prevented the defendants’ experts [as well as the plaintiffs’ experts] from testifying on direct examination to the out-of-court opinions of other scientists in the absence of some specific exception to the hearsay rule [none was shown].”).
Regarding Section 703(b), unless the evidence is capable of only one interpretation, the question to the expert witness must refer to specific portions of the record. See Connor v. O’Donnell, 230 Mass. 39, 42, 119 N.E. 446, 447 (1918).
Regarding Section 703(c), in determining whether facts or data are independently admissible, it is not whether the forms in which such facts or data exist satisfy evidentiary requirements. Rather, the court will determine whether the underlying facts or data would potentially be admissible through appropriate witnesses. Such witnesses need not be immediately available in court to testify. See Commonwealth v. Markvart, 437 Mass. 331, 337–338, 771 N.E.2d 778, 783 (2002), citing Department of Youth Servs. v. A Juvenile, 398 Mass. at 531, 499 N.E.2d at 820–821.
Limitation on Cross-Examination. On cross-examination of an expert, a judge may exclude evidence as unfairly prejudicial, see Section 403, even if the expert is aware of those facts, if the facts were not relied upon as part of the expert’s opinion, do not clarify or discredit the opinion, and serve only to focus the jury on those facts. Commonwealth v. Anestal, 463 Mass. 655, 667–668, 978 N.E.2d 37, 47–48 (2012) (prior bad acts excluded).
Risk of Inaccurate Forensic Analysis. In Commonwealth v. Barbosa, 457 Mass. 773, 933 N.E.2d 93 (2010), the Supreme Judicial Court addressed the risk of inaccurate forensic analysis as follows:
“Our common-law rules of evidence protect a defendant in various ways from the risk of inaccurate forensic analysis. Where there is reason to believe that evidence has been mislabeled or mishandled or that data have been fabricated or manipulated, a defendant may challenge the admissibility of an expert opinion relying on such evidence or data in a Daubert-Lanigan hearing, because an opinion must rest on evidence or data that provide ‘a permissible basis’ for an expert to formulate an opinion. A defendant may also challenge the admissibility of an opinion where an expert relies solely on the conclusions of the testing analyst, without knowledge of the procedures employed by the testing analyst or the underlying data and evidence that are generally contained in worksheets, because a conclusory opinion alone may not be a permissible basis on which an expert may rest an opinion. Where an expert opinion survives a Daubert-Lanigan challenge or where . . . the defendant does not challenge the admissibility of the expert’s opinion, the defendant may still . . . cross-examine the testifying expert as to the risk of evidence being mishandled or mislabeled or of data being fabricated or manipulated, and as to whether the expert’s opinion is vulnerable to these risks.” (Citations omitted.)
Id. at 790–791, 933 N.E.2d at 110.
On direct examination, the expert witness may testify to the basis of his or her opinion regarding (1) facts within the witness’s personal knowledge; (2) facts in evidence; or (3) with approval of the court, facts that a party will put in evidence. However, “it is settled that an expert witness may not, under the guise of stating the reasons for his opinion, testify to matters of hearsay in the course of his direct examination unless such matters are admissible under some statutory or other recognized exception to the hearsay rule.” Commonwealth v. Nardi, 452 Mass. 379, 392, 893 N.E.2d 1221, 1232 (2008), quoting Grant v. Lewis/Boyle, Inc., 408 Mass. 269, 273, 557 N.E.2d 1136, 1138–1139 (1990), quoting Kelly Realty Co. v. Commonwealth, 3 Mass. App. Ct. 54, 55–56, 323 N.E.2d 350, 351–352 (1975).
DNA Analyst. A DNA analyst may testify to testing he or she performed on unknown samples, but may not testify about the testing conducted by an absent analyst. In accordance with Section 705, a DNA analyst may testify to his or her opinion even though the basis is in whole or in part evidence collected or created by the absent DNA analyst. See Commonwealth v. Greineder, 464 Mass. 580, 583–584, 984 N.E.2d 804, 807–808 (2013).
Medical Examiner. A substitute medical examiner may not testify to the observations, findings, or opinions made by an absent medical examiner. In accordance with Section 705, a medical examiner may testify to his or her opinion even though the basis is in whole or in part evidence collected or created by the absent medical examiner. Commonwealth v. Leng, 463 Mass. 779, 785, 979 N.E.2d 199, 206 (2012); Commonwealth v. Nardi, 452 Mass. 379, 388, 893 N.E.2d 1221, 1229 (2008). The Commonwealth is not required to show that the medical examiner who performed an autopsy is unavailable for a substitute medical examiner to testify. Commonwealth v. Reavis, 465 Mass. 875, 881–882, 992 N.E.2d 304, 310–311 (2013).
Cross-Reference: Section 702, Testimony by Experts; Section 705, Disclosure of Facts or Data Underlying Expert Opinion; Article VIII, Introductory Note.