464 Mass. 580 | Mass. | 2013
This case is again before us after the United States Supreme Court, in Greineder v. Massachusetts, 133 S. Ct. 55 (2012), vacated the judgment and remanded Commonwealth v. Greineder, 458 Mass. 207 (2010) (Greineder), to this court. The remand came with instructions to give the case further consideration in light of the recent Supreme Court decision in Williams v. Illinois, 132 S. Ct. 2221 (2012) (Williams). Our review proceeds accordingly, and we conclude that Williams does not require us to change our jurisprudence.
1. Greineder. A recitation of the underlying facts is unnecessary as the facts have been fully set forth in our decision in Greineder, supra, which we incorporate by reference. We do, however, briefly recount our previous determination that the
2. Massachusetts evidentiary rule on bases of expert opinion testimony. We begin our analysis of the continued validity of our approach to protecting the confrontation right of criminal defendants with a brief review of the Massachusetts evidentiary rule on expert opinion testimony and its permissible bases. The traditional rule was that an expert’s opinion had to be based either on evidence in the record or on facts of which the expert
Although facts and data not in evidence may form the basis of an expert witness’s opinion testimony, the expert may not present on direct examination the specific information on which he or she relied, see Commonwealth v. McNickles, 434 Mass. 839, 857 (2001), and cases cited, because expert testimony to the “fact[s] of the test results obtained by someone else . . . [is] hearsay.” Commonwealth v. Evans, 438 Mass. 142, 152 (2002), cert, denied, 538 U.S. 966 (2003). See Commonwealth v. Cohen, 412 Mass. 375, 393 (1992), quoting McCormick, Evidence § 246, at 729 (3d ed. 1984) (defining hearsay as statement, other than one made by declarant testifying at trial or hearing, offered in evidence to prove truth of matter asserted). The expert may, however, be required to disclose the facts or data that formed the basis of the expert opinion on cross-examination. See Mass. G. Evid., supra at § 705, at 223. Disallowing direct testimony to the hearsay basis of an expert opinion helps prevent the offering party from slipping out-of-court statements not properly in evidence in through the “back door” (citation omitted). Department of Youth Servs. v. A Juvenile, supra. Our prohibition of expert testimony concerning a nontestifying analyst’s test results (even where those results formed the basis of the expert’s opinion), on grounds that such basis evidence is offered for its truth and, therefore, is hearsay, differs from evidentiary rules in some other jurisdictions. Under Rule 703 of the Federal Rules of Evidence, for example, an
In Massachusetts, we draw a distinction between an expert’s opinion on the one hand and the hearsay information that formed the basis of the opinion on the other, holding the former admissible and the latter inadmissible. See Department of Youth Servs. v. A Juvenile, supra at 531-532. See also Barbosa, supra at 783-784 (“Where a Commonwealth expert testifies to her own opinion, the opinion is not hearsay, because the declarant of the opinion is testifying at trial”). The admission of expert opinion but exclusion of its hearsay basis protects a criminal defendant’s Federal and State constitutional right to confront witnesses. Id. at 783 (“our evidentiary rules and the Sixth Amendment are in harmony”). Expert opinion testimony, even if based on facts and data not in evidence, does not violate the right of confrontation because the witness is subject to cross-examination concerning his or her expert opinion and the reliability of the underlying facts and data. Id. at 785-786.
3. Nexus between rules of evidence and right of confrontation. To illustrate “the intersection between our common-law rules of evidence concerning expert testimony and the constitutional right of confrontation,” id. at 783, we highlight several foundational cases decided in the wake of the Supreme Court’s monumental Sixth Amendment decision in Crawford v. Washington, 541 U.S. 36 (2004) (Crawford),
Several years after Crawford, supra, we considered the admissibility of expert opinion and testimony to its basis in Com
Two years later,
In 2011, the Supreme Court addressed the constitutional sufficiency of “surrogate” testimony, or testimony of a person who did not perform or observe the laboratory analysis described in a blood alcohol report the prosecution sought to admit, as a vehicle for the admission of the nontestifying analyst’s findings. Bullcoming v. New Mexico, 131 S. Ct. 2705, 2709, 2714-2717 (2011) (Bullcoming). In its five-to-four decision in Bullcoming, the Court held that the nontestifying analyst’s report indicating
Later that year, in Commonwealth v. Munoz, 461 Mass. 126, 131-138 (2011), vacated and remanded, 133 S. Ct. 102 (2012) (Munoz),
The Williams Court held that the admission of statements that disclosed information about underlying DNA testing performed by a nontestifying analyst that formed the basis of the expert opinion did not violate the Sixth Amendment. Id. at 2228, 2240, 2244. The five Justices that reached this conclusion, however, differed in their reasoning. The plurality (four Justices) determined that the expert’s basis evidence was not offered for its truth. Id. at 2228, 2231-2232, 2235, 2239-2240. Therefore, the underlying facts that formed the basis of the opinion were admissible under Crawford because Crawford “does not bar the use of testimonial statements for purposes other than establishing the truth of the matter asserted.” Id. at 2235, quoting Crawford, supra at 59-60 n.9. Justice Thomas determined that admission of the expert’s testimony to the underlying basis of her expert opinion did not violate the Sixth Amendment because the
“There was nothing wrong with [the expert’s] testifying that two DNA profiles — the one shown in the . . . report and the one derived from [the defendant’s] blood — matched each other; that was a straightforward application of [the expert’s] expertise. Similarly, [the expert] could have added that if the . . . report resulted from scientifically sound testing of [a DNA sample recovered from the victim], then it would link [the defendant] to the assault. What [the expert] could not do was what she did: indicate that the . . . report was produced in [a particular] way . . . ” Id. at 2270 (Kagan, J., dissenting).
Thus, no member of the Supreme Court plainly concluded that the expert opinion testimony was improper. See id. at 2235-2236
5. Import of Williams. Of great significance for our present purposes is that Williams focused on the admissibility of evidence of the basis of the expert’s independent opinion, and not the admissibility of the expert opinion itself. See id. at 2227, 2236, 2240 (plurality opinion). Five members of the Supreme Court concluded, albeit for different reasons, that such basis evidence is admissible without violating a defendant’s confrontation right. See id. 2244 (plurality opinion), 2245, 2248 (Breyer, J., concurring), 2255 (Thomas, J., concurring in the judgment). As we explained earlier, under Massachusetts jurisprudence, a forensic expert’s opinion that relies on the data or conclusions of a nontestifying analysis is bifurcated from its basis. We allow an expert to testify to his or her independent opinion even if based on data not in evidence; we do not allow expert witnesses to testify to the specifics of hearsay information underlying the opinion on direct examination. See Nardi, supra at 392-393; Commonwealth v. McNickles, 434 Mass. 839, 857 (2001). Thus, our rules of evidence differ from the Illinois evidentiary rule implicated in Williams that, like the Federal rule, allows an expert to disclose the data on which the expert’s opinion is based for the nonhearsay purpose of explaining its basis. Williams, supra at 2234-2235, 2239-2240 (discussing Ill. R. Evid. 703 and Fed. R. Evid. 703). The expert witness’s testimony in Williams that implicated the DNA test results of a nontestifying analyst “would have been . . . improper under long-standing Massachusetts law.” Commonwealth v. Munoz, supra at 133. Moreover, five Justices concluded that an expert’s disclosure of the underlying facts from an unadmitted DNA report went to its truth and not the limited purpose of explaining the basis for the expert opinion. See Williams, supra at 2256-2257 (Thomas, J., concurring in the judgment); id. at 2268 (Kagan, J., dissenting). This reasoning supports the Massachusetts rule that an expert’s testimony to the fact of a nontestifying analyst’s test results is hearsay. See Nardi, supra at 392.
Thus, our rules of evidence and the protections they afford
6. Application. Forensic expert opinion testimony, even if based on independently admissible facts or data not in evidence, does not violate a criminal defendant’s confrontation rights for two principal reasons. First, an expert witness is subject to
First, as concerns the opportunity to cross-examine a forensics expert about his or her opinion, the defendant argues that the expert witness here did not, in fact, offer her independent opinion, but instead merely parroted the conclusions in Cellmark’s report of the DNA test results. The multiple reports submitted by Cell-mark included statistical calculations on the frequency that the genetic makeup recovered from evidence collected from the crime scene appears in the population, as well as conclusions regarding whether the defendant could be excluded as a source of DNA obtained from these samples. Nonetheless, and as we determined previously, the record reflects that Dr. Cotton reviewed the nontestifying analyst’s work, including six prepared reports, and then conducted an independent evaluation of the data.
Second, the Massachusetts Association of Criminal Defense Lawyers (association), as amicus curiae, contends that an expert
Here, not only did the defendant have a meaningful opportunity to cross-examine Dr. Cotton on the reliability of the data that formed the basis of her expert opinion, his experienced trial counsel used the opportunity effectively. Trial counsel reviewed Cellmark’s DNA testing process with Dr. Cotton on cross-examination, and had her acknowledge aspects of the process not governed by standard protocols. He challenged Dr. Cotton on Cellmark’s minimum interpretation thresholds that, although they were raised mid-analysis, were still below testing thresholds used elsewhere. Greineder, supra at 238. Trial counsel also elicited information from Dr. Cotton concerning how data filtering may affect DNA test results. A significant portion of trial counsel’s cross-examination of Dr. Cotton was devoted to attacking the reliability of Cellmark’s reported test results. Id. at 239. Thus, to the extent that DNA test results, with their “strong scientific underpinning,” see Barbosa, supra at 788 n.13, quoting National Research Council, Strengthening Forensic Science
7. A bifurcated approach: admitting opinion, but excluding its hearsay basis on direct examination. The defendant challenges our bifurcation of admissible expert opinion from its inadmissible, hearsay basis. He argues that the two elements — the underlying facts that form the basis of an expert opinion and the expert opinion itself — are inextricably linked, at least in the context of DNA analysis. We disagree. There is a clear distinction between the allelic information that establishes genetic makeup and the statistical significance of the data that establishes how frequently a genetic combination appears in the population at large. See Commonwealth v. Vao Sok, 425 Mass. 787, 789, 790-791 (1997) (discussing alleles), 791 (statistical analysis). As we said in Barbosa, supra at 789, it is the statistical significance of a DNA match that is of greatest use to a jury; information about the prevalence of a particular gene combination gives meaning to the underlying fact of allelic presence. See Commonwealth v. McCowen, 458 Mass. 461, 484 (2010), citing Barbosa, supra (“the admission of the raw DNA testing results alone, even where the allele numbers match, is meaningless to a jury”). Admittedly, Justice Kagan, dissenting in Wz7-liams, approached the relationship between underlying facts and the resultant opinion in the DNA context from a different end.
In support of its view that our evidentiary bifurcation of admissible expert opinion from its inadmissible hearsay basis on direct examination is not sufficiently protective of defendants’ confrontation right,
Granted, in this case, Dr. Cotton did testify to the details and results of the nontestifying analyst’s DNA test results. Greineder, supra at 236-237. We held then and repeat now that this evidence elicited on direct examination was admitted in error. Id. at 237. We maintain, however, that the defendant was not prejudiced by the erroneous admission. As we determined in Greineder, supra at 239:
“Defense counsel made extensive use of the data prepared by [the nontestifying analyst] in his cross-examination of Dr. Cotton. This cross-examination buttressed two pillars of the defense, namely, the unreliability of Cellmark’s testing procedures, which necessarily affected the credibility of Dr. Cotton’s opinion as to the high probability of the defendant’s being a contributor to the DNA on the knife and brown gloves, and the defense theory that a third party committed the murder. . . . Both strategies depended entirely on the use of [the nontestifying analyst’s] data in*603 cross-examination of Dr. Cotton. . . . The data were an integral part of the defense, and it was going to be the subject of inquiry by the defense whether [the nontestify-ing analyst] testified or not.”
8. Conclusion. For the reasons discussed above, Dr. Cotton’s expert opinion that the defendant’s DNA matched the DNA on items recovered from the crime scene was properly admitted. Expert opinion testimony, even that which relies for its basis on the DNA test results of a nontestifying analyst not admitted in evidence, does not violate a criminal defendant’s right to confront witnesses against him under either the Sixth Amendment or art. 12 of the Massachusetts Declaration of Rights. Nothing in the Supreme Court’s decision in Williams v. Illinois, 132 S. Ct. 2221 (2012), is to the contrary. Dr. Cotton’s direct testimony to the details of the DNA test results of a nontestifying analyst, however, was improperly admitted. Because the defendant was not prejudiced by the erroneous admission, we affirm his conviction and the denial of his motion for a new trial.
So ordered.
We acknowledge the amicus briefs submitted by the Committee for Public Counsel Services; the Massachusetts Association of Criminal Defense Lawyers; and the Attorney General and the district attorneys for the Berkshire, Bristol, Cape and the Islands, Essex, Hampden, Middlesex, Northwestern, Suffolk, and Worcester districts.
The defendant did not argue that art. 12 of the Massachusetts Declaration of Rights provides greater protection than the Sixth Amendment to the United States Constitution, and we did not address that issue. Commonwealth v. Greineder, 458 Mass. 207, 237 n.9 (2010) (Greineder).
The Supreme Court, in Crawford v. Washington, 541 U.S. 36, 59 (2004) {Crawford), held that “[tjestimonial statements of witnesses absent from trial [can be] admitted only where the declarant is unavailable, and only where the defendant has had a prior opportunity to cross-examine.”
There is an important distinction between satisfying the mandates of common-law evidentiary rules and satisfying the mandates of the confrontation clauses of the Federal and State Constitutions. In criminal cases, out-of-court statements are only admissible if they satisfy both; failure to satisfy either the applicable rules of evidence or the Federal and State Constitutions will result in the exclusion of evidence. See generally Mass. G. Evid., Introductory Note to art. VDI (2012), and cases cited.
Although we concluded that the expert’s testimony to the findings in the autopsy report on direct examination was admitted in error, we nonetheless determined that, in the circumstances of the particular case, its admission did not create a substantial likelihood of a miscarriage of justice and, therefore, a new trial was unwarranted. See Commonwealth v. Nardi, 452 Mass. 379, 395-396 (2008) (Nardi).
In the interim, in Melendez-Diaz v. Massachusetts, 557 U.S. 305, 308-309,
testimony to the hearsay basis underlying the expert opinion did not create a substantial likelihood of a miscarriage of justice and, thus, did not warrant retrial. See Barbosa, supra at 792-793 (same).
For descriptions of deoxyribonucleic acid (DNA) testing, see Commonwealth v. Vao Sok, 425 Mass. 787, 789 792 (1997), and Commonwealth v. Curnin, 409 Mass. 218, 227 231 (1991) (Appendix).
Here, Dr. Cotton presented her opinion on the statistical likelihood that the DNA recovered from the crime scene that matched the defendant’s DNA profile would match an unrelated person in the general population. Greineder, supra at 217-218. See Commonwealth v. Vao Sok, supra at 791 (statistical significance of DNA analysis). She testified, for example, that a statistical analysis based on the match at four loci of the defendant’s DNA to DNA recovered from the knife found at the crime scene “indicated that one in 1,400 unrelated African Americans and one in 2,200 unrelated Caucasians would be included with the defendant as possible secondary” sources of the DNA. Greineder, supra at 217. She further testified that “statistical analysis indicated one in fifteen million unrelated African Americans, and one in 680,000 unrelated Caucasians could be included with the defendant as possible contributors” to DNA recovered from a left hand glove; and that “one in 680 million unrelated African-Americans and one in 170 million unrelated Caucasians would be included with the defendant as possible secondary contributors” to DNA recovered from a right hand glove similarly recovered from the crime scene. Id. at 217-218. Such statistical information is necessary because approximately “99.9% of DNA is identical between any two individuals”; only the remaining .1% of DNA is particular to a given individual. Federal Judicial Center, Reference Manual on Scientific Evidence 491 (2d ed. 2000). See Commonwealth v. Vao Sok, supra at 789, quoting Commonwealth v. Cumin, 409 Mass. 218, 228 (1991).
As in Greineder, the Supreme Court vacated the judgment in Munoz, supra, and remanded it for further consideration in light of Williams v. Illinois, 132 S. Ct. 2221 (2012) (Williams). Munoz v. Massachusetts, 133 S. Ct. 102 (2011). The defendant in Munoz decided not to pursue the appeal before this court.
In Munoz, the Commonwealth conceded that the expert’s testimony on direct examination that implicated a nontestifying analyst’s data and conclusions violated the defendant’s confrontation rights and was admitted in error. Munoz, supra at 130, citing Barbosa, supra at 186. Thus, the issue in Munoz, supra at 131-133, was only whether Bullcoming v. New Mexico, 131 S. Ct. 2705, 2710 (2011) (Bullcoming), mandated a change in the Massachusetts evidentiary rules that permit expert opinion testimony even if based on testimonial hearsay. We concluded that it did not. Munoz, supra at 133.
The Williams plurality distinguished Williams from Bullcoming on the ground that, in Williams, the expert’s reference to the underlying forensic report, which was not introduced in evidence, was (at least, ostensibly) not offered to prove the truth of the matter asserted in the report. Williams, supra at 2240. In contrast, according to the Williams plurality, the forensic report admitted in evidence through the testimony of a “surrogate” witness in Bullcoming, supra, was unquestionably offered for its truth. Id.
The plurality, in an alternative conclusion, also determined that the expert’s basis testimony was admissible because the report that included the underlying DNA test results was not testimonial. Williams, supra at 2242-2244. However, the test the plurality employed in determining that the nontestifying analyst’s DNA test results were not “testimonial” differed from the test Justice Thomas employed to reach the same conclusion. Compare id. at 2242-2243 (primary purpose), with id. at 2255, 2259-2264 (Thomas, J., concurring in the judgment) (formality and solemnity). We address the issue whether the DNA test results in this case qualified as “testimonial.” See note 15, infra.
In determining that Williams, supra, does not undermine our jurisprudence, we mirror our approach in Munoz, supra at 131-136, in which we evaluated the continued validity of our bifurcation of expert opinion from its hearsay basis in light of the Supreme Court’s decision in Bullcoming, supra. There we noted that Bullcoming concerned the admission of evidence (a forensic report prepared by a nontestifying analyst via a surrogate witness) that would not have been admissible under Massachusetts law. Munoz, supra at 132-133. Our prohibition of an expert’s direct testimony about the underlying facts that formed the basis of the opinion “essentially, [is] a different way of stating the central holding of Bullcoming: that a substitute analyst cannot testify to, or otherwise introduce, the original analyst’s reports and conclusions on direct examination.” Id. at 133. Similarly, Williams concerns the constitutionality of the admission of expert basis evidence that would not have been admissible in Massachusetts because it is hearsay. See Williams, supra at 2256-2257 (Thomas, J., concurring in the judgment); id. at 2268 (Kagan, J., dissenting). Therefore, Williams does not undercut our evidentiary rule that sufficiently safeguards defendants’ confrontation right.
That our rules of evidence preclude an expert from testifying on direct examination to the hearsay information that formed the basis of his or her opinion is reason enough for its exclusion. Nevertheless, we also conclude that Dr. Cotton’s testimony regarding the DNA analyst’s test results was admitted in error for the additional reason that the nontestifying analyst’s report was testimonial. See Commonwealth v. McCowen, 458 Mass. 461, 483 (2010). Although the precise contours of the “primary purpose” test are arguably in flux following Williams, the report in the present case is distinguishable from the report in Williams because Cellmark Diagnostics laboratory (Cellmark) had the defendant’s DNA sample. See, e.g., Williams, supra at 2243. This indicates that the defendant was targeted as a suspect at the time Cellmark conducted DNA testing, and demonstrates that the DNA testing was conducted for the purpose of obtaining evidence for later use at trial. Thus, as we determined previously, “a reasonable person in [the nontestifying analyst’s] position would anticipate her findings and conclusions being used against the accused in investigating and prosecuting a crime.” Greineder, supra at 237, quoting Nardi, supra at 394. See Commonwealth v. Avila, 454 Mass. 744, 763 n.20 (2009), quoting Nardi, supra (same as to autopsies).
As it was in the present case, unfiltered or raw data, in addition to filtered data, should be made available to DNA expert witnesses, as well as to defense counsel during discovery. Unfiltered or raw data shows all peaks detected by the machine, whereas an analyst may limit the DNA peaks that a computer detects. Providing an expert with unfiltered data puts the expert in the best position to formulate an independent opinion and to respond to questions concerning the risk that evidence was fabricated or manipulated. See Barbosa, supra at 791. Beyond ensuring that data are made available to the expert witness, we decline to delve more deeply into an expert witness’s trial preparation process. We leave that to the “crucible of cross-examination." Crawford, supra at 61. Where the expert has not reviewed the raw data, defense counsel may use this to gain an advantage. Such was the circumstance of the present case: the expert had only reviewed the filtered, printed data (as opposed to the raw, electronic data), which defense counsel then used to impeach the expert’s testimony.
DNA test results may, for example, contain “artifacts,” or false indications of allelic presence. See Commonwealth v. Bly, 448 Mass. 473, 481 (2007). See also Commonwealth v. Buckman, 461 Mass. 24, 35-36 (2011), cert, denied, 132 S. Ct. 2781 (2012). Dr. Cotton testified that it is common for the computer to label a peak as an allele and the analyst to override that call. However, the fact that a nontestifying analyst may use his or her independent judgment in generating a DNA profile does not indicate that the resulting data are inherently unreliable or that an expert cannot be meaningfully cross-examined about the process of DNA analysis.
“Alleged defects in the chain of custody usually go to the weight of the evidence and not its admissibility.” Commonwealth v. Viriyahiranpaiboon, 412 Mass. 224, 230 (1992), citing Commonwealth v. White, 353 Mass. 409, 419-420 (1967), cert, denied, 391 U.S. 968 (1968). Of course, the prosecution is strongly encouraged to offer conventional chain of custody evidence to establish the source of the sample tested, such as the testimony of the person who recovered the DNA sample, the testimony of the person who had custody of the sample before it was sent to the laboratory, and shipping manifests to show the sample was sent to and returned from the laboratory. See Williams, supra at 2239. Although an expert witness may not be competent to testify to the chain of custody of the particular DNA sample, a DNA match is “itself striking confirmation” that the laboratory tested the correct sample. Id. at 2238 (“there is simply no plausible explanation for how [the laboratory] could have produced a DNA profile that matched [the defendant] if [the laboratory] had tested any sample other than the one [recovered from the crime scene]”).
In the context of DNA forensics, we strongly encourage the Commonwealth,
Although it is clear from the record that Cellmark had a known sample of the defendant’s DNA, it is not clear whether the nontestifying analyst who authored the DNA test reports accessed known samples of the defendant’s DNA while simultaneously interpreting the unknown samples. However, in response to the defendant’s memorandum in support of his motion for a new trial and a supplemental affidavit of Dr. Arthur Eisenberg, a former chairman of the United States DNA advisory board to the Federal Bureau of Investigations whom the defense retained to analyze Cellmark’s work in the present case, Dr. Cotton submitted an affidavit in which she stated that it was “decidedly contrary” to Cellmark’s practice and to accepted scientific practices to access known samples while interpreting unknown samples. Dr. Cotton also stated that, although the risk of “unconscious bias” exists, Cellmark’s protocols are designed to address that possibility, and “it would have been foolish to compromise our integrity by biasing our analysis toward a particular result.” Moreover, the fact that there was also evidence of a stranger’s DNA on a glove recovered from the crime scene, Greineder, supra at 238-239, demonstrates that DNA testing was not geared toward matching the defendant’s DNA profile.
“Only an expert can testify to the likelihood that more than one person possesses a particular DNA profile, based on her knowledge of the alleles selected for the DNA profile and the mathematical probabilities that more than one person may possess the same characteristics of those alleles.” Barbosa, supra at 789. See Williams, supra at 2252 & Appendix at 2253-2255 (Breyer, J., concurring) (distinguishing technician’s production of electropherogram indicating allelic presence at given loci from analyst’s conclusion about significance of DNA test results).
The Committee for Public Counsel Services, as amicus curiae, urges us to abandon our reliance on our evidentiary rule barring inquiry on direct examination about the testimonial hearsay basis of an expert opinion as a means of protecting criminal defendants’ confrontation right. It points us to language in Justice Thomas’s concurrence and the dissent in Williams to the effect that State evidentiary rules should not define constitutional requirements. See Williams, supra at 2256 (Thomas, J., concurring in the judgment); id. at 2272
In many of the cases we have decided since Crawford, supra, that implicated a defendant’s confrontation right in the context of expert opinion testimony, we upheld the defendant’s conviction. See, e.g., Greineder, supra at 239, 256. In Commonwealth v. Durand, 457 Mass. 574, 581 (2010), however, we held that the direct testimony of two doctors to autopsy report findings of a nontestifying examiner was admitted in error, and that the error was not harmless beyond a reasonable doubt. Thus, we reversed the conviction and remanded the case for a new trial. Commonwealth v. Durand, supra at 575, 601.
A Daubert-Lanigan hearing also protects a defendant from the risk of inaccurate forensics. Barbosa, supra at 790-791. At a Daubert-Lanigan hearing, a defendant may challenge the admissibility of an expert opinion that is based on evidence that the defendant expects was somehow tainted or not subject to the expert’s thorough review on ground that an expert must have a “permissible basis” to support his or her opinion. Id., quoting Department of Youth Servs. v. A Juvenile, 398 Mass. 516, 531 (1986). See Williams, supra at 2241 (noting additional safeguards preventing admission or improper use of expert basis evidence); id. at 2249 (Breyer, J., concurring) (professional guidelines ensure reliability of forensic test results).