Opinion ID: 886539
Heading Depth: 1
Heading Rank: 4

Heading: issues

Text: ¶ 27 Did the District Court err in denying Ayers' motion in limine to exclude testimony using the likelihood ratio in presenting DNA results? ¶ 28 During the autopsy, swabs from each of Phyllis's breasts were collected and examined for evidence. Analysis at the State crime lab revealed the presence of Amylase, which is an enzyme found in saliva, on both swabs. However, because the crime lab was relocating its facility at the time, the swabs were sent to a private laboratory, the Laboratory Corporation of America (LabCor) for DNA profiling. Further analysis showed both male and female markers in the sample from the left breast, and Ayers could not be excluded as a contributor of the DNA alleles found in the left breast sample. ¶ 29 Because the samples were so small, LabCor used the polymerase chain reaction method (PCR) for analyzing the DNA evidence. LabCor's analysis showed that DNA found in the swab from the right breast was consistent with Phyllis and while there was a trace amount of additional DNA, it failed to meet reporting standards. LabCor's DNA profile of the left breast swab indicated a mixture of DNA from more than one individual, and LabCor concluded that neither Phyllis, nor Ayers, could be excluded as contributors of the genetic material from that swab. LabCor did not conduct a statistical analysis on this sample, because at that time it was not its policy to conduct such an analysis on mixed samples. On request of the State, the data was forwarded to Dr. Chris Basten (Dr. Basten), a Research Associate Statistician at North Carolina State University. Using LabCor's DNA testing results, Dr. Basten performed a type of calculation analysis known as a LR (likelihood ratio) to explain the relevance of the evidence. ¶ 30 LabCor conducted PCR analysis on the breast swabs. PCR testing is often used when the provided sample is small, since PCR allows the technician to amplify the DNA extracted from the sample by making millions of copies of the areas on the chromosome they wish to analyze. Here, both breast swabs contained what is referred to as a mixed samplethat is, it contained alleles from two or more individuals. According to the final report for the left breast sample, LabCor ran seven different genetic markers, and for all seven, it found alleles that were consistent with being contributed by either Phyllis or Ayers. LabCor concluded that there was nothing in those alleles that indicated there was another possible contributor to that mixed sample. To analyze the relevance of the evidence, Dr. Basten explained that since the DNA evidence came from a mixed sample, he used the LR to allow comparison of differing explanations for how it came about. ¶ 31 The LR, which is a ratio of conditional probabilities, is a measure of the strength of a piece of evidence in distinguishing between hypotheses. See State v. Garcia (Ariz.Ct.App.1999), 197 Ariz. 79, 3 P.3d 999, 1000, fn. 1 (citing Geoffrey K. Chambers et al., Forensic DNA Profiling: The Importance of Giving Accurate Answers to the Right Questions, 8 Crim. L.F. 445, 454-55 (1997)). The LR is used to evaluate how strong a proposition or hypothesis is by comparing it to another explanation. Here, the State's theory (or hypothesis) was that the two contributors to the left breast DNA evidence were Phyllis and Ayers. To evaluate how strong that proposition was, it had to be compared to another explanation, such as the hypothesis that Phyllis and an unknown individual were the contributors. Here, based on Ayers' general denial of guilt, Dr. Basten calculated the probability of the evidence under each one of those theories ( i.e., he ran an algorithm of the different possible combinations of alleles at all the different genetic markers, or loci) and then compared them by taking a ratio of those two probabilities. ¶ 32 Dr. Basten explained the LR calculation in this way: [I]n order to asses how strong a proposition is, or any explanation is, you have to compare it to another explanation. So, usually you have one explanation that's offered by the prosecution. We usually call that the prosecution explanation. Then to determine how strong that explanation is, how strong that result is, you devise another explanation. We can refer to that as the defense explanation, and there may be a number of those. Then what you do is you calculate the probability of the evidence under each one of those scenarios, and you compare them by taking a ratio of those two probabilities.... [When phrasing the results of the ratio we are] always talking about the likelihood of the evidence under two different scenarios. We're never talking about the likelihood that he's the contributor or not, but the evidence if he's the contributor versus the evidence that he's not the contributor. ¶ 33 In calculating the LR, Dr. Basten relied on formulas set forth by a group of genetic statisticians in an article published in the Journal of Forensic Sciences in 1997. See Bruce S. Weir, et al., Interpreting DNA Mixtures, 42 J. Forensic Sci. 213 (1997). According to Dr. Basten, the statistical formulas have been subjected to peer review and publication. Based on his calculations, Dr. Basten concluded that the evidence ( i.e., DNA sample from the left breast swab), was 330,000 times more likely if it came from the defendant and the victim than if it came from the victim and some unknown [person]. Or stated another way, the evidence is 330,000 times more likely under the prosecution hypothesis than one specific alternate hypothesis. ¶ 34 On appeal, Ayers argues that Dr. Basten's expert testimony should have been excluded on the following grounds: 1) the LR is a novel statistical evidence technique and should therefore be subject to analysis under Daubert v. Merrell Dow Pharmaceuticals, Inc. (1993), 509 U.S. 579, 113 S.Ct. 2786, 125 L.Ed.2d 469; 2) the computer program used by Dr. Basten was not reliable or generally accepted, and could not be verified; 3) Dr. Basten was unable to do the calculations in the courtroom; and 4) the LR formula used by Dr. Basten was based on assumptions which did not consider real population characteristics. ¶ 35 The admissibility of expert testimony is governed by Rule 702, M.R.Evid., which provides: If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education may testify thereto in the form of an opinion or otherwise. A district court is vested with great latitude in ruling on the admissibility of expert testimony. State v. Southern, 1999 MT 94, ¶ 48, 294 Mont. 225, ¶ 48, 980 P.2d 3, ¶ 48 (quoting Durbin v. Ross (1996), 276 Mont. 463, 477, 916 P.2d 758, 767) (emphasis in original). ¶ 36 As we have repeatedly stated, the test for admissibility of expert testimony is whether the matter is sufficiently beyond common experience that the opinion of the expert will assist the trier of fact to understand the evidence or to determine a fact in issue. Southern, ¶ 49 (citation omitted). Therefore a trial court must first determine whether the subject matter of the testimony is one that requires expert testimony, and whether the particular witness is qualified as an expert to give an opinion in the particular area on which he or she proposes to testify. Southern, ¶ 49 (citation omitted). Finally, Rule 702, M.R.Evid., implicitly requires a foundation showing that the expert has special training or education and adequate knowledge on which to base an opinion. Southern, ¶ 49. ¶ 37 Although Ayers asserts that the LR is unreliable under Daubert, we conclude that the Daubert standard is inapplicable here since that standard applies only to the admissibility of novel scientific evidence. Hulse, ¶¶ 56-57 (affirming our holding in State v. Cline (1996), 275 Mont. 46, 55, 909 P.2d 1171, 1177, that all scientific expert testimony is not subject to the Daubert standard and the Daubert test should only be used to determine the admissibility of novel scientific evidence). ¶ 38 In Hulse, we concluded that the Horizontal Gaze Nystagmus (HGN) test was not novel scientific evidence, noting that for several decades, law enforcement officials had used the HGN test, and that as early as 1986, the admissibility of the HGN test had been considered in other jurisdictions. We cited with approval the Minnesota Supreme Court comment that the HGN test `can hardly be characterized as an emerging scientific technique' because nystagmus has long been known and the tests have been in common medical use for many years. Hulse, ¶ 68 (citing State v. Klawitter (Minn.1994), 518 N.W.2d 577, 584). ¶ 39 Likewise, we concluded in Southern that microscopic hair comparison evidence was not novel scientific evidencenoting that since 1978 we had considered several cases wherein witnesses had testified on such evidence and that comparing hair samples with a microscope had been done for decadesand therefore Daubert standards were not applicable to determine its admissibility. Southern, ¶ 59. ¶ 40 While it is clear from our prior decisions that there is no set standard for determining whether a scientific technique is novel, we have consistently given credence not only to previous treatment of the technique by other cases and jurisdictions, but also to how long the technique or theory has been used in the scientific community. Applying those standards here, we conclude that the LR is not a novel scientific technique. ¶ 41 First, according to Dr. Basten, the widely used paternity statistic known as paternity index or probabilities of paternity is basically the same thing as a likelihood ratio. A paternity index calculation considers the genetic evidence from a mother, child, and putative father and compares the hypothesis that the putative father is the father versus the hypothesis that another man is the father. According to Dr. Basten, while the specific equations might be slightly different between a paternity index (dealing with mother, child, and putative father) and the LR in a criminal investigation (suspect, victim and evidence stain), both involve the same theory: you're calculating the probability of what you see, evidence or data, given different ideas as to how it came about. ¶ 42 In State v. Weeks, the State presented statistical analysis based on a paternity test to prove the defendant had sexual intercourse without consent with his thirteen-year old stepdaughter who became impregnated. Weeks (1995), 270 Mont. 63, 891 P.2d 477 (The statistical analysis determined the defendant was 154,000 times more likely to be the father of his stepdaughter's baby). Dr. Basten, having reviewed Weeks, explained that the paternity index used in that case was basically a LR. ¶ 43 During the pre-trial hearing, Dr. Basten told the court that in at least six previous cases, his testimony was based on the LR, including a Montana case tried in 1998, State v. Swan, Fourth Judicial District Court, Missoula County, Cause No. 12594 (neither the admission of DNA evidence, nor the LR were appealed in that case). Moreover, Dr. Basten also testified in Garcia, 197 Ariz. 79, 3 P.3d 999, where the Arizona Supreme Court concluded that interpretation of mixed DNA samples using statistical formulas for calculating LR's were generally accepted by the relevant scientific community and were therefore admissible under Frye v. United States (D.C.Cir.1923), 293 F. 1013. ¶ 44 Second, we take note of many journal articles written on the topic of presenting DNA results which incorporate discussion of the LR. See, e.g., Jonathan J. Koehler, On Conveying the Probative Value of DNA Evidence: Frequencies, Likelihood Ratios, and Error Rates, 67 U. Colo. L.Rev. 859 (1996); William C. Thompson, DNA Evidence in the O.J. Simpson Trial, 67 U. Colo. L.Rev. 827, 828 (1996); Jonathan J. Koehler, Why DNA Likelihood Ratios Should Account for Error (Even When A National Research Council Report Says They Should Not), 37 Jurimetrics J. 425 (1997). ¶ 45 Based upon the foregoing authority, we conclude that the LR is not a novel scientific technique that warrants analysis under Daubert. However, we must still determine its admissibility under a conventional Rule 702, M.R.Evid., analysis. See State v. Hocevar, 2000 MT 157, ¶ 58, 300 Mont. 167, ¶ 58, 7 P.3d 329, ¶ 58; Southern, ¶¶ 59-60; and Hulse, ¶ 69. ¶ 46 First, we have stated that expert testimony is required in areas not within the range of ordinary training or intelligence. Hocevar, ¶ 58 (citing Hulse, ¶ 48). Based on our review of the intricacies and mathematical principles underlying calculation of the LR and other statistical analyses related to DNA evidence, we conclude that the LR is a subject matter that requires expert testimony. ¶ 47 Second, the record clearly indicates that Dr. Basten is qualified to testify as an expert witness on the basis of both his educational background and his experience. In fact, Ayers does not challenge Dr. Basten's qualifications as an expert on the LR. Rather, Ayers attacks the veracity and reliability of the specific computer program and methodology that Dr. Basten used. ¶ 48 We have noted that criticisms of specific applications of procedures or concerns about the accuracy of test results does not render the scientific theory and methodology invalid or destroy their general acceptance. These questions go to the weight of the evidence, not the admissibility. Weeks, 270 Mont. at 83, 891 P.2d at 489 (citation omitted). Moreover, we have consistently stated that it is better to admit relevant scientific evidence in the same manner as other expert testimony and allow its weight to be attacked by cross-examination and refutation. Southern, ¶ 50 (citing Barmeyer v. Montana Power Co. (1983), 202 Mont. 185, 193-94, 657 P.2d 594, 598, overruled on other grounds by Martel v. Montana Power Co. (1988), 231 Mont. 96, 752 P.2d 140). See also, State v. Moore (1994), 268 Mont. 20, 42-43, 885 P.2d 457, 471, overruled on other grounds by State v. Gollehon (1995), 274 Mont. 116, 906 P.2d 697 (even though the foundation for the State's expert witness was shaky, the district court did not err in ruling the defendant's objection to the DNA evidence went to the weight, and not the admissibility, of the evidence). Finally, [n]ot every error in the application of a particular methodology should warrant exclusion. An alleged error in the application of a reliable methodology should provide the basis for exclusion of the opinion only if that error negates the basis for the reliability of the principle itself. Moore, 268 Mont. at 42, 885 P.2d at 471 (citation omitted). ¶ 49 While we recognized in Weeks, 270 Mont. at 84, 891 P.2d at 489 (citation omitted), that courts must be mindful that the probative value of statistical probabilities evidence is not outweighed by any unfair prejudicial effect, we conclude that admission of Dr. Basten's conclusions using the LR did not unfairly prejudice Ayers. At both the hearing on his motion in limine and the trial, Ayers had the opportunity to cross-examine Dr. Basten concerning the computer program he used to run the formula, his methodology, and his application of various sampling error standards. While Ayers identified two expert witnesses at the pre-trial hearing, Ayers chose not to present an expert at trial to refute or challenge Dr. Basten's calculations, methodology, or formulas. ¶ 50 We conclude that the issues concerning Dr. Basten's techniques/methods went to the weight of the evidence, not its admissibility. Based on the foregoing, we further conclude the District Court did not abuse its discretion when it allowed Dr. Basten to testify using the LR.