The defendant misunderstands the structural defect doctrine. A structural error is one that so infringes on a defendant’s right to the basic components of a fair trial that it can never be considered harmless. See Arizona v. Fulminante,
There was no such risk here. The Commonwealth introduced the cocaine the police found in the defendant’s apartment and the corresponding certificates of analysis. “When properly executed, [a certificate of analysis] shall be prima facie evidence of the composition, quality, and when requested, the net weight of the narcotic . . . analyzed . . . .” G. L. c. 111, § 13, as amended by St. 1982, c. 650, § 18. See Commonwealth v. Johnson,
Commonwealth v. Chotain,
Expert police testimony. Trooper Matthews, a back-up officer, testified that “somebody who would have in his possession this amount of cocaine is a substantial trafficker in cocaine.” The codefendants objected and moved to strike; the defendant did not. The trial judge sustained the objection but apparently did not instruct the jury to disregard the trooper’s testimony. No one sought clarification. Arguing that this testimony permitted the officer to testify to the defendant’s guilt, the defendant claims its introduction created a substantial risk of a miscarriage of justice. Commonwealth v. Freeman, 352 Mass, at 563-564.
The admission of expert opinion testimony is largely within the sound discretion of the judge and will be reversed only where the admission constitutes an abuse of discretion or error of law. Commonwealth v. Johnson, 410 Mass, at 202. “[T]he subject matter discussed [was] within the witness’s field of expertise and ... the witness [did] not directly express his views on the defendant’s guilt.” Commonwealth v. Tanner,
Judgment affirmed.
