425 Mass. 819 | Mass. | 1997
A Superior Court jury convicted the defendant, Jeffrey Fowler, of rape of a child with the use of force and murder in the first degree (by reason of extreme atrocity or cruelty) of the two year old daughter of the woman with whom he was living at the time. After sentencing, the trial judge, sua sponte, set aside the guilty verdicts and ordered a new trial. See Mass. R. Grim. P. 25 (b) (2), 378 Mass. 896 (1979). The Commonwealth appeals from that order and the judge’s subsequent order denying the Commonwealth’s motion for reconsideration. We vacate the order setting side the verdicts and ordering a new
I
The Commonwealth sought to introduce in evidence deoxyribonucleic acid (DNA) test results to establish that the defendant was the source of semen recovered from an autopsy swabbing of the victim’s mouth. Forensic testing by the Federal Bureau of Investigation (FBI), using the Restriction Fragment Length Polymorphism (RFLP) method of analysis of DNA,
Prior to trial, the defendant filed a motion in limine seeking to exclude any use of or reference to DNA evidence. The defendant did not challenge the RFLP analysis,
The product rule now meets the test of scientific reliability stated in Commonwealth v. Lanigan, 419 Mass. 15, 16 (1994) (Lanigan II). See Commonwealth v. Rosier, ante 807, 813-814 (1997). But its use has been — and was at the time of the hearing — a subject of controversy. In 1992, the National Research Council (NRC)
At the voir dire hearing Mertens testified that the FBI did not agree with the NRC about the existence of genetic subpopulations. Nevertheless, he said, the FBI had conducted an additional statistical analysis in this case using the ceiling principle. Calculated according to that principle, he said the chance of a random match of DNA from the autopsy swabbing from the victim and someone other than the defendant would be approximately one in 159,000.
Because the defendant’s expert was not available at the time of the voir dire hearing, the judge made no ruling at that time; the evidence was closed “temporarily,” subject to an expert’s being called by the defendant. The trial commenced on November 29, 1993. On December 1, 1993, although the defendant had still called no DNA expert to testify, the judge again heard arguments from counsel concerning the admissibility of the Commonwealth’s DNA evidence. The judge denied the defendant’s motion in limine on December 6. On December 8, Mertens was called by the Commonwealth to testify. He told the jury that there was a match between the defendant’s DNA
The only basis on which Mueller sought to challenge the Commonwealth’s DNA evidence concerned the FBI’s purported failure to follow certain procedural steps in connection with its statistical analyses using the ceiling principle.
A few days after Dr. Mueller had given his voir dire testimony, and as the trial progressed, the judge denied the defendant’s attempt to exclude the testimony of Mertens that the jury previously had heard. Dr. Mueller never testified before the jury. On December 17, 1993, the jury convicted the defendant. The defendant promptly moved pursuant to rule 25 (b) (2) that the judge enter verdicts of not guilty, or order a new trial. The judge denied the motion. On January 7, 1994, the defendant was sentenced to life in prison pursuant to G. L. c. 265, § 1, on the murder conviction, and to a concurrent life sentence on the rape conviction.
On February 11, 1994, the judge sua sponte issued a statement on the record in which he said that he had reconsidered the defendant’s postconviction motion under rule 25 (b) (2), and
n
Under rule 25 (b) (2),
In Commonwealth v. Vao Sok, ante 787, 796-798 (1997), we today explain the standard we exercise when reviewing a trial judge’s ruling on the admissibility of scientific evidence.
Applying these standards of review, we turn to the judge’s rulings concerning the admissibility of the Commonwealth’s DNA evidence, in particular the scientific reliability of the statistical models used by the Commonwealth to describe the significance of the DNA match. This requires that we describe first a development in the relevánt scientific community that occurred after the posttrial motions in this case. In 1996 the NRC issued a new report entitled The Evaluation of Forensic DNA Evidence (1996 NRC Report), in which the NRC revised its earlier view on the ceiling principle analysis. The 1996 NRC Report at 5 recommended that in general the calculation of a
The judge did not, of course, have the benefit of the 1996 NRC Report. In his 1994 ruling, made before our decision Lanigan II, he concluded that the ceiling principle, and its application here, did not meet the requirements of scientific reliability. In his March, 1995, order denying the Commonwealth’s motion to reconsider, he “assume[d] without deciding” that the ceiling and interim ceiling principles were scientifically valid, but concluded that the FBI’s application of the interim ceiling principle was unreliable. It is now clear that the concerns that the judge had, both with respect to the interim ceiling principle
As described above, the 1996 NRC Report repudiated the need for the ceiling principle analysis, and any possible failings of the FBI in executing the ceiling principle (and, in light of that Report, we are not persuaded that there were any such failings) are also laid to rest.
In our two-pronged review of the admission of scientific evidence, we afford great deference to the decisions of trial judges concerning the reliability of the application of a scientific technique in a particular case. But in this case all of the judge’s concerns stem from challenges to the ceiling principle that have since been resolved by the 1996 NRC Report and related studies.
The order setting aside the defendant’s verdicts and granting the defendant a new trial is vacated and the jury’s verdicts of murder in the first degree and rape are reinstated. Sentence is to be imposed in the Superior Court.
So ordered.
There are different methods used in DNA forensic testing, including RFLP and polymerase chain reaction (PCR) amplification and allele identification. See Commonwealth v. Vao Sok, ante 787, 789-792 (1997). RFLP analysis identifies and analyzes genetic loci containing different numbers of copies of genetic base sequences, called “variable number of tandem repeats” (VNTRs). See Commonwealth v. Curnin, 409 Mass. 218, 227-230 (1991). For a comparison of the RFLP- and PCR-based methods of DNA forensic testing, see Vao Sok, supra at 790-792. The PCR-based method of analysis is not at issue in this case.
The RFLP method of analysis has been found to be scientifically reliable. Commonwealth v. Lanigan, 419 Mass. 15, 27 (1994) (Lanigan II). Commonwealth v. Daggett, 416 Mass. 347, 350 n.1 (1993).
Under United States v. Frye, 293 F. 1013 (D.C. Cir. 1923), a party offering evidence produced by a scientific theory or process had “the burden of showing the general acceptance by experts in the field of the reliability” of that evidence. Commonwealth v. Kater, 388 Mass. 519, 527 (1983). In Commonwealth v. Cumin, supra at 227, applying the Frye test, we held that the admission in evidence of DNA test results constituted prejudicial error where there was an absence of general acceptance or inherent rationality of the process by which the testing laboratory arrived at the probability of file DNA match occurring in the population at large.
In 1993, the Supreme Court decided Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), in which it held that Fed. R. Evid. 702 superseded the Frye test. Id. at 588. Rule 702 imposes a duty on the trial judge to make an initial determination whether scientific testimony and
“We accept the basic reasoning of the Daubert opinion because it is consistent with our test of demonstrated reliability. We suspect that general acceptance in the relevant scientific community will continue to be the significant, and often the only, issue. We accept the idea, however, that a proponent of scientific opinion evidence may demonstrate the reliability or validity of the underlying scientific theory or process by some other means, that is, without establishing general acceptance.”
See Commonwealth v. Sands, 424 Mass. 184, 185-186 (1997).
We discussed the product rule in Commonwealth v. Curnin, supra at 224, and in Commonwealth v. Rosier, ante 807, 813 (1997). In brief, “[u]nder the product rule, the frequency in the population base of each allele disclosed in the DNA test is multiplied to produce the frequency of the combination of all the alleles found.” Lanigan II, supra at 21, citing Commonwealth v. Curnin, supra at 224 n.10, 225 n.11.
Although Mertens did not use the precise term, the procedure he described at the voir dire hearing for calculating the DNA match frequency statistic was the product rule model, as the judge noted in his order granting the defendant a new trial.
The National Research Council is an association of leading scientists, the members of which are drawn from the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine.
For a discussion of the ceiling principle, see Commonwealth v. Lanigan, 413 Mass. 154, 163 (1992) (Lanigan I); Commonwealth v. Daggett, supra at 356-357 n.1 (Abrams, J., concurring); Lanigan II, 419 Mass. 15, 27 (1994); Commonwealth v. Rosier, supra at 814-815.
Although the record does not reflect any ruling by the judge that Mertens could not testify before the jury about the FBI’s analysis of the DNA samples using the product rule, the record suggests that the judge was greatly concerned about the admissibility of testimony concerning the product rule in light of the dispute concerning its reliability within the scientific community at that time.
As noted above, the defendant never challenged the RFLP method of analyses used by the FBI, and he never suggested that any aspect of the FBI’s DNA profiling — other than the ceiling principle statistical analysis — was scientifically unreliable or invalid in any respect. As the judge noted in his March, 1995, order denying the Commonwealth’s motion for reconsideration, “the only part of the DNA evidence challenged by the defendant under the Frye-Cumin standard, was the statistical procedure, known as the ‘ceiling’ method, used to calculate the significance of a laboratory match of DNA profiles.”
Mueller testified that the 1992 NRC Report contained three permanent recommendations: (1) that all forensic laboratories base their statistical analyses on a collection of fifteen to twenty ethnic subgroup database populations rather than use three or four different racial categories; (2) that the product rule be replaced by the ceiling principle for calculating the probability of a DNA match in the general population; and (3) that laboratories report to juries the false positive rate in order to indicate the probability that the laboratory might incorrectly match DNA samples.
Mueller further testified that the 1992 NRC Report had recognized that it would take some time for laboratories to collect samples for the fifteen to twenty ethnic subgroup database populations, and had therefore made two “interim” recommendations for laboratories to follow while they assembled the ethnic subgroup database populations. These interim recommendations, Mueller said, are (1) that laboratories use a “counting method,” by which the
In determining whether a DNA fragment from one sample matches another DNA fragment, the fragments’ sizes are compared. The range within which DNA fragments of different sizes cannot be reliably distinguished is called a “bin.” DNA fragments within a bin are treated as though they are the same size. See S. Easteal, N. McLeod & K. Reed, DNA Profiling: Principles, Pitfalls and Potential 193 (1991). Under the fixed bin analysis, the boundaries of a bin are determined by the position of DNA fragments of known size. Under a floating bin analysis, the bins’ boundaries are determined by making repeated measurements of the same DNA fragments run on different gels used in the separation of the fragments. Id. at 92.
Dr. Mueller used fixed bins, floating bins with a 5% statistical interval, and floating bins with a 9% statistical interval, respectively.
In Lanigan II, supra at 26-27, we upheld the admission at Lanigan’s trial of evidence of the significance of a DNA match, calculated according to the ceiling principle.
Rule 25 of the Massachusetts Rules of Criminal Procedure, 378 Mass. 986 (1979), provides in relevant part:
“(a) Entry By Court. The judge on motion of a defendant or on his own motion shall enter a finding of not guilty of the offense charged in an indictment . . . after the evidence on either side is closed if the evidence is insufficient as a matter of law to sustain a conviction on the charge. ...
“(b) (2) Motion After Discharge Of Jury. If the motion is denied and the case is submitted to the jury, the motion may be renewed within five days after the jury is discharged and may include in the alternative a motion for a new trial. If a verdict of guilty is returned, the judge may on motion set aside the verdict and order' a new trial, or order the entry of a finding of not guilty, or order the entry of a finding of guilty of any offense included in the offense charged in the indictment or complaint.”
That standard of review is relevant here. The judge emphasized that he was allowing the defendant’s postconviction rule 25 (b) (2) motion for a required finding of not guilty, not as an exercise of discretion, but as a matter of law, because “there was no general acceptance within the relevant scientific community of the ceiling method or interim ceiling method as a reliable statistical calculation, [and] as a matter of law, neither the evidence of the laboratory DNA ‘match’, nor the statistical evidence interpreting that ‘match’, should have been admitted at trial under the Frye-Cumin standard.”
In Rosier, supra at 817, we said that “[w]e agree with the conclusions of the 1996 NRC Report,” and recognized the scientific validity of the product rule in the context of the PCR-based method of analysis of DNA samples. The product rule has validity as well in the context of the RFLP method of analysis used in this case. The 1996 NRC Report recognizes that the ceiling principle, developed in response to concerns about the possibility of genetic subpopulations, was of particular significance in calculating VNTR profile frequencies, such as the profile frequencies in this case. See note 1, supra. The 1996 NRC Report’s conclusion, supra at 158, that the ceiling principle and interim ceiling principle were “excessively conservative,” and its conclusion that the product rule should be used in making profile frequencies is applicable to VNTR-based systems, such as the RFLP. Id. at 5.
In anticipation that some laboratories might still use the ceiling principle analysis, the 1996 NRC Report made recommendations “that will make the [ceiling] principle more workable and less susceptible to creative misapplications.”
A 1993 report produced by the FBI, entitled VNTR Population Data: A Worldwide Study, arrived at a similar conclusion that the product rule was valid and that the data do not support the need for alternative procedures, such as the ceiling principle. See Rosier, supra at 815 n.16.
The judge identified four “failings” of the FBI in its analysis using the interim ceiling principle, none of which withstands scrutiny in light of the 1996 NRC Report. The judge found that “the FBI did not apply the counting method statistical calculation and instead used a corrective mathematical ceiling approach for which there was no support in the relevant scientific community." The 1996 NRC Report discredits any requirement that the “counting method” be used. Id. at 159-160. Second, the judge said “the FBI failed to use all of the databases at its disposal.” The 1996 NRC Report validates the use by the FBI of the population groups in this case. Third, the judge concluded that, “although the NRC did not recommend that a laboratory’s error rate in conducting an interim ceiling calculation should be told to the jury, as the NRC stated should be done for a standard ceiling test, Dr. Mueller stated that such an error-rate report should also be made to the jury for any interim ceiling tests.” The 1996 NRC Report, at 185, explicitly declined to make such a recommendation, commenting that “[ijnasmuch as the purpose of our report is to determine what aspects of the procedures used in connection with forensic DNA testing are scientifically valid, we attempt no such policy judgment” (emphasis supplied). Finally, the judge noted that “although the FBI used the ‘fixed-bin’ method instead of the ‘floating-bin method’ as recommended by the NRC, this is not fatal to the FBI’s calculation because the NRC also stated that fixed-bin method was ‘acceptable’ for purposes of the interim ceiling approach.” This is consistent with the 1996 NRC Report at 162.
The lack of prejudicial error resulting from admitting the Commonwealth’s evidence of the DNA profile frequency is further evidenced by the limited range of men who could have been the source of the semen found in the victim’s mouth. It is undisputed that the victim, a two year old child, had contact with few people (all identified) in the days immediately preceding her death. The Commonwealth accounted for the last days of the victim’s life, and tested the DNA of the only four males who had contact with the victim in the days immediately preceding her death: the defendant; the victim’s father; a friend of the father; and the victim’s maternal grandfather. The Commonwealth’s expert testified that all but the defendant were eliminated as the source of the semen found in the victim’s mouth.
As Mertens testified, the FBI studies indicated that genetic subpopulations did not exist and therefore the ceiling principle analysis was not needed. But to the extent there was any doubt about that, the ceiling principle eliminated any effect that the subpopulations might have and added “further level of conservativeness to an already conservative system” to the statistical analyses using the product rule. The defendant’s expert agreed.