Opinion ID: 1154894
Heading Depth: 2
Heading Rank: 2

Heading: Admission of, and foundation for, DNA evidence

Text: Arresting officers noticed blood on Defendant's shirt. During the next few months, Cellmark Diagnostic Laboratories, Inc. (Cellmark) performed DNA testing on this blood as well as the victim's bone and muscle samples. Test results showed a match between the DNA in the blood on Defendant's shirt and the DNA in the victim's muscle sample. Further testing in 1990 showed that the DNA in the blood on the shirt did not match Defendant's DNA. The State moved for a Frye hearing to determine the admissibility of the DNA test results. See United States v. Frye, 293 F. 1013 (D.C. Cir.1923). After an extensive hearing, the trial court found that the DNA testing performed was generally accepted in the relevant scientific community and admitted the results at trial. Defendant challenges this finding. For criminal cases, DNA testing is a very recent advent. In October 1988, an appellate court first considered the admissibility of DNA testing in the criminal context. See William C. Thompson & Simon Ford, DNA Typing: Acceptance and Weight of the New Genetic Identification Tests, 75 Va.L.Rev. 45, 46 n. 4 (1989) (Thompson & Ford, DNA Typing ) (citing Andrews v. State, 533 So.2d 841 (Fla.Ct.App. 1988), review denied, 542 So.2d 1332 (Fla. 1989)). In the years following Andrews, courts in more than forty states have considered DNA evidence in hundreds of cases. National Research Council, Summary, DNA Technology in Forensic Science 21-22 (1992) (NRC Summary, DNA Technology ). DNA contains the genetic code for all living organisms and is present in every cell containing a nucleus. Christopher G. Shank, Note, DNA Evidence in Criminal Trials: Modifying the Law's Approach to Protect the Accused from Prejudicial Genetic Evidence, 34 Ariz.L.Rev. 829, 829, 832 n. 27 (1992). DNA is composed of several component parts, including four different base pairs. See State v. Cauthron, 120 Wash.2d 879, 846 P.2d 502, 508 (1993). The precise sequence of these base pairs in certain DNA segments determines genetic traits. Id. The segments of DNA that determine these genetic traits are called alleles. State v. Pennell, 584 A.2d 513, 516 (Del.Sup.Ct. 1989). The basis for DNA identity testing is the well-accepted proposition that except for identical twins each individual has a unique overall genetic code. William C. Thompson & Simon Ford, DNA Testing: Debate Update, 28 Trial, Apr. 1992, at 52, 52 (Thompson & Ford, DNA Testing ). Present technology, however, does not permit testing of the entire DNA sequence but only of discrete, very limited DNA segments. Because 99.9% of the DNA sequence in any two people is identical, D.H. Kaye, The Admissibility of DNA Testing, 13 Cardozo L.Rev. 353, 354 (1991), accurate analysis is vital to determine whether there is a match of the remaining 0.1 percent of the DNA sequence from the samples compared. Stated very simply, [14] there are three general steps in DNA testing: 1. Creating a DNA print or profile of a sample; 2. Determining whether the prints or profiles of different samples match; and 3. If samples match, computing the probability of a random match. NRC Summary, DNA Technology at 6, 8. Cellmark used restriction fragment length polymorphism (RFLP) testing in this case. [15] Cellmark, Lifecodes Corporation, and the FBI are the three major laboratories currently performing RFLP DNA testing in the United States. Thompson & Ford, DNA Testing at 52. Testing protocols for these laboratories are not identical. NRC Summary, DNA Technology at 15; see also State v. Anderson, 853 P.2d 135, 142-43 (N.M.Ct.App.), cert. granted, 115 N.M. 145, 848 P.2d 531 (1993). [16] Defendant does not challenge DNA testing in toto. Indeed, Defendant concedes general acceptance of the underlying theory of DNA testing and its research and diagnostic uses. Rather, Defendant makes three main challenges to the admission of the DNA test results in this case: 1. The trial court erred by declining to determine before trial whether the tests were properly conducted and accurately recorded according to Cellmark's own protocol. 2. There is no general acceptance in the relevant scientific community of the procedures used by Cellmark to declare a match. 3. There is no general acceptance in the relevant scientific community of the procedures used by Cellmark to calculate the statistical probability of a random match and, thus, the court erred in admitting statistical probability opinion testimony. We first turn to the question of what standard to apply in determining admissibility. [17]
Both before and after the adoption of the Arizona Rules of Evidence, we have used the Frye test in determining whether to admit new scientific evidence. See, e.g., State v. Velasco, 165 Ariz. 480, 486, 799 P.2d 821, 827 (1990); State ex rel. Collins v. Superior Court, 132 Ariz. 180, 195-202, 644 P.2d 1266, 1281-88 (1982); State v. Valdez, 91 Ariz. 274, 277-80, 371 P.2d 894, 896-98 (1962). But see State v. Olivas, 77 Ariz. 118, 119, 267 P.2d 893, 894 (1954) (scientific disagreement [as to certain blood alcohol tests] affects only the weight and not the admissibility of evidence.). Frye helps us determine whether new scientific principles are ready for the courtroom and, conversely, whether the courtroom is ready for new scientific principles: Just when a scientific principle or discovery crosses the line between the experimental and demonstrable stages is difficult to define. Somewhere in this twilight zone the evidential force of the principle must be recognized, and while courts will go a long way in admitting expert testimony deduced from a well recognized scientific principle or discovery, the thing from which the deduction is made must be sufficiently established to have gained general acceptance in the particular field in which it belongs. Frye, 293 F. at 1014. Under Frye, we conduct a de novo review to determine whether a scientific principle used as a basis for expert testimony is generally accepted in the relevant scientific community. See, e.g., People v. Barney, 8 Cal. App.4th 798, 10 Cal. Rptr.2d 731, 737 (1992); State v. Vandebogart, 616 A.2d 483, 491 (N.H. 1992); Cauthron, 846 P.2d at 505-06. The State argues that the Arizona Rules of Evidence effectively supersede the Frye test and asks that we reject Frye for a relevancy standard under Ariz.R.Evid. 401-03 and 702-06. It is impossible for our system of justice to ignore scientific and technological advances. Nevertheless, scientific evidence is a source of particular judicial caution. State v. Superior Court, 149 Ariz. 269, 276, 718 P.2d 171, 178 (1986). Because `science' is often accepted in our society as synonymous with truth, there is a substantial risk of overweighting by the jury. Morris K. Udall, et al., Arizona Practice  Law of Evidence § 102, at 212 (3d ed. 1991). Similarly, because neither judge nor jury may be able to separate junk science from good science, Frye helps guarantee that reliability will be assessed by those in the best position to do so: members of the relevant scientific field who can dispassionately study and test the new theory. Superior Court, 149 Ariz. at 277, 718 P.2d at 179. Frye helps protect courts from unproven, and potentially erroneous and misleading, scientific theory until a pool of experts is available to evaluate it in court. 1 John W. Strong, et al., McCormick on Evidence § 203, at 873 (4th ed. 1992). Other benefits of Frye are uniformity of evidentiary rulings and avoiding complex evidentiary presentations in succeeding cases after a particular principle is judicially recognized. Id. When general acceptance is found, the scientific theory may be applied in other cases without further proof of acceptance. The Frye test, however, has significant shortcomings. New discoveries are not immediately accepted in the scientific community. Rigid application of the general acceptance test would forbid judicial use of a new discovery even though there may be direct experimental or clinical support for the principle. Furthermore, history shows that generally accepted scientific theory is not always correct. Due in part to these concerns, a leading commentator writes that a drumbeat of criticism ... provides the background music to the movement away from the general acceptance test. 1 McCormick on Evidence § 203, at 873. Although acknowledging Frye's worthwhile objectives, this commentator's further observations are worth repeating: [ Frye 's] objectives can be attained satisfactorily with less drastic constraints on the admissibility of scientific evidence. In particular, it has been suggested ... that courts look directly to reliability or validity rather than to the extent of acceptance, ... and that the traditional standards of relevancy and the need for expertise  and nothing more  should govern. ... [This suggestion] avoids the difficult problems of defining when scientific evidence is subject to the general acceptance requirement and how general this acceptance must be, of discerning exactly what it is that must be accepted, and of determining the particular field to which the scientific evidence belongs and in which it must be accepted. General scientific acceptance is a proper condition for taking judicial notice of scientific facts, but it is not a suitable criterion for the admissibility of scientific evidence. Any relevant conclusions supported by a qualified expert witness should be received unless there are distinct reasons for exclusion. These reasons are the familiar ones of prejudicing or misleading the jury or consuming undue amounts of time. This traditional approach ... permits general scientific opinion of both underlying principles and particular applications to be considered in evaluating the worth of the testimony.... Furthermore, unlike the general or the substantial acceptance standards, it is sensitive to the perceived degree of prejudice and unnecessary expense associated with the scientific technique in issue. Not every scrap of scientific evidence carries with it an aura of infallibility. Some methods, like bitemark identification and blood splatter analysis, are demonstrable in the courtroom. Where the methods involve principles and procedures that are comprehensible to a jury, the concerns over the evidence exerting undue influence and inducing a battle of the experts have less force. On the other hand, when the nature of the technique is more esoteric, as with some types of statistical analyses and serologic tests, or when the inferences from the scientific evidence sweep broadly or cut deeply into sensitive areas, a stronger showing of probative value should be required.... By attending to such considerations, the rigor of the requisite foundation can be adjusted to suit the nature of the evidence and the context in which it is offered. 1 McCormick on Evidence § 203, at 873-76 (emphasis added and footnotes omitted); see generally Mark McCormick, Scientific Evidence: Defining a New Approach to Admissibility, 67 Iowa L.Rev. 879 (1982). Faced with similar arguments, the United States Supreme Court recently held that the Federal Rules of Evidence superseded Frye. See Daubert v. Merrell Dow Pharmaceuticals, Inc., ___ U.S. ___, ___, 113 S.Ct. 2786, 2794, 125 L.Ed.2d 469 (1993). Daubert, however, did not open the courtroom door to all scientific evidence. The federal trial judge still is the evidentiary gatekeeper. Proposed testimony must be supported by appropriate validation  i.e., `good grounds,' based on what is known. In short, the requirement that an expert's testimony pertain to `scientific knowledge' establishes a standard of evidentiary reliability. Id. at ___, 113 S.Ct. at 2795. Noting that scientific validity for one purpose is not necessarily scientific validity for other, unrelated purposes, id., Daubert held that federal trial judges must make a preliminary assessment of whether the reasoning or methodology underlying the testimony is scientifically valid and of whether that reasoning or methodology properly can be applied to the facts in issue, id. at ___, 113 S.Ct. at 2796. The Court then made some general observations, offering several factors bearing on that inquiry. Id. at ___-___, 113 S.Ct. at 2796-98. Daubert 's general observations, for the most part, correspond with the factors discussed above in the quotation from McCormick on Evidence. Both provide persuasive reasons for rejecting or modifying Frye when applying the Arizona Rules of Evidence, which in relevant part are identical to the federal rules. The federal rules, however, are legislatively-enacted and interpreted by the United States Supreme Court as [it] would any statute. Daubert, ___ U.S. at ___, 113 S.Ct. at 2793. Our rules, on the other hand, are court-enacted. See Ariz. Const. art. VI, § 5(5); Ariz.R.Sup.Ct. 28. While the United States Supreme Court considers congressional purpose, this court  when construing a rule we have adopted  must rely on text and our own intent in adopting or amending the rule in the first instance. See Ritchie v. Grand Canyon Scenic Rides, 165 Ariz. 460, 464-68, 799 P.2d 801, 805-09 (1990). Furthermore, we are not bound by the United States Supreme Court's non-constitutional construction of the Federal Rules of Evidence when we construe the Arizona Rules of Evidence. Finally, Daubert itself does not establish a regime based solely on the qualification of experts and relevance. See Fed.R.Evid. 702. The Daubert analysis includes a reliability requirement for [p]ertinent evidence based on scientifically valid principles. Daubert, ___ U.S. at ___, 113 S.Ct. at 2799. The nature of this requirement is currently unknown, may vary from case to case, and is to be fashioned by trial judges using an analytical framework as yet unspecified. In application, Daubert leaves many questions unanswered. See id. at ___, 113 S.Ct. at 2800 (Rehnquist, C.J., concurring in part and dissenting in part). We conclude, therefore, that notwithstanding legitimate criticism of Frye, and our desire to preserve uniformity when possible, this is not the case to determine whether Arizona should follow Daubert. Although the argument has been raised by the State, it has not been extensively briefed or argued. More important, however, even were we to use Daubert 's reliability/scientific validity analysis, we would still be left with the problem posed by Frye: precisely when in [the] twilight zone the evidential force of the [scientific] principle must be recognized. Frye, 293 F. at 1014. Whether the Frye or Daubert standard is used, that line is hard to draw for DNA testing, a subject that fuels even greater scientific ferment and controversy than the legal controversy engendered by Frye. The science in question makes line-drawing in this case particularly difficult. Not only are we in a complex scientific field, but the technology is still evolving. Furthermore, this is not an area in which the jury can easily penetrate the aura of infallibility, nor one in which the principles are easily demonstrable in the courtroom. See 1 McCormick on Evidence § 205, at 897-900. The trial testimony shows it is an area in which the scientists themselves have yet to settle on uniform testing techniques or protocols. Finally, as we discuss more fully below, see infra § C(5), the science in this area can have a direct and forceful dispositive effect. As one court put it, DNA testing is precisely the sort of scientific evidence which requires application of the Frye test. Fishback v. People, 851 P.2d 884, 890 (Colo. 1993). In short, the difficulties of addressing the technology used in this case may well promote an evidentiary rule not suitable for many other types of cases. The field of DNA testing is probably the worst subject to use to decide whether or how to refine, replace, or abolish Frye. Nor, as will be seen, is there a need to do so in this case. Thus, for the present at least, we resolve this case without significant change in existing evidentiary law. We leave Daubert for another day and, in accordance with Arizona precedent  old and new  apply Frye as we turn to Defendant's arguments. 3. The scope of the Frye hearing and the foundation for DNA testing If Frye is satisfied, scientific evidence is admissible subject to a foundational showing. State ex rel. Collins, 132 Ariz. at 196, 644 P.2d at 1282; see also NRC Summary, DNA Technology at 23 (The adequacy of the method used to acquire and analyze samples in a given case bears on the admissibility of the evidence and should, unless stipulated by opposing parties, be adjudicated case by case.). In this case, this foundational showing was made in the jury's presence at trial, and the court ruled that a proper foundation had been made. Claiming this was error, Defendant argues that the foundational showing should have been made at the Frye hearing rather than in front of the jury. Case law is split on this issue. See People v. Castro, 144 Misc.2d 956, 545 N.Y.S.2d 985, 987 (Sup.Ct. 1989) (citing authority). Some courts require an initial foundational showing outside of the presence of the jury and, if adequate, repeat that showing before the jury. Id. Other courts allow the foundational showing to be made solely before the jury. Id. The foundation needed when Frye is satisfied relates to the expert's qualifications, proper application of testing techniques, and accurate recording of test results. See State ex rel. Collins, 132 Ariz. at 196, 644 P.2d at 1282. If the foundational showing is made in the jury's presence, and if the showing is inadequate, aside from valuable trial time wasted, the jury would be exposed to prejudicial proofs and left to speculate as to why the defendant opposed the ultimate result. United States v. Two Bulls, 918 F.2d 56, 60 (8th Cir.1990), vacated on other grounds, 925 F.2d 1127 (8th Cir.1991) (en banc). Mistrial or reversible error could occur if an inadequate foundational showing was made before the jury. Simply put, in a rare case  where the scientific principle and necessary foundational showing are highly controversial and hotly contested  allowing the foundational showing to be made in front of the jury means that the trial court works without a net. The trial court, however, has discretion in deciding whether a foundational showing is to be made outside the jury's presence. See Ariz.R.Evid. 103(c), 104(c). Although acknowledging the potential for reversible error in using such a procedure, we hold that the trial court is not required to hold a foundational hearing outside the jury's presence. Furthermore, in this case the court did not err by allowing the foundation to be made before the jury. At trial, the State made a proper foundational showing (as opposed to, and distinct from, the Frye finding discussed below) for the performance of the DNA testing. The laboratory personnel had adequate qualifications, the test used was that described by the Cellmark testing protocol, and the results were properly recorded. Although Defendant surmises that samples might have been switched, he cites to no compelling evidence supporting this hypothesis, and we have found none. Thus, in this case, no error resulted from allowing the foundational showing to be made in the presence of the jury. Therefore, we move to the substantive Frye issue. 4. Is there general acceptance in the relevant scientific community of Cellmark's techniques and standards used to declare a match? A final product of DNA testing of a sample is an x-ray film called an autoradiograph or autorad. Cauthron, 846 P.2d at 509. An autorad contains several bands and looks like a bar code with the bands representing different polymorphic DNA segments. Id. at 509-10. To determine whether two samples match, Cellmark first visually compares the samples' banding patterns. If they visually match, Cellmark measures and compares the banding patterns of the two samples. A match is declared if each band varies in position less than one or two millimeters from the corresponding band in the other sample. In this case, all bands in the declared matches varied less than plus or minus one millimeter. Unlike Cellmark, after finding a visual match, the FBI and Lifecodes use a standard deviation or percent variation analysis to determine whether samples match. Defendant claims that Cellmark's match standard is not generally accepted in the relevant scientific community. The accuracy of a match declaration is very important. A declared match means that the samples could have come from the same individual. Conversely, if samples do not match, they must have come from different individuals. See infra note 20. At least initially, declaring any match involves some subjectivity. Indeed, one court has stated that mere visual comparisons might be generally accepted even without objective verification. See Perry v. State, 606 So.2d 224, 225 (Ala.Ct.Crim. App. 1992). Cellmark's match criteria have objective verification, and other courts have found that these criteria comply with Frye. See Barney, 10 Cal. Rptr.2d at 738-40; People v. Axell, 235 Cal. App.3d 836, 1 Cal. Rptr.2d 411, 425-29 (1991); Fishback, 851 P.2d at 892-93; Pennell, 584 A.2d at 517-19; Polk v. State, 612 So.2d 381, 391-93 (Miss. 1992); State v. Pierce, 64 Ohio St.3d 490, 597 N.E.2d 107, 113-14 (1992); see also Caldwell v. State, 260 Ga. 278, 393 S.E.2d 436, 443 (1990) (visual match, coupled with band shift test, admissible). Defendant advances no good argument that these cases were wrong when decided or that, because of scientific development, their analysis is now obsolete. Furthermore, our own independent research reveals no significant scientific controversy over Cellmark's method of declaring a match. Thus, we hold that Cellmark's match criteria are generally accepted in the relevant scientific community and comply with Frye. 5. Population genetics  general acceptance of Cellmark's statistical probability calculation of a random match
Cellmark's Lisa Forman, Ph.D., testified that, given a match of the autorads from the blood on Defendant's shirt and the victim's tissue, the probability of a random match ranged from one in fourteen billion to, more conservatively, one in sixty million. The State tacitly attempted to argue that these probability figures could be equated with the probability that someone other than Defendant committed the crime. [18] Defendant contends that the court erred in admitting the Cellmark statistical probability evidence because it is not generally accepted by population geneticists  the relevant scientific community.
Absent laboratory error, a declared match means that only one of the following is true: (1) the samples came from the same individual; (2) the samples came from identical twins; [19] or (3) the samples came from different individuals but, by pure chance, the DNA segments examined match (although comparison of the entire DNA sequence from each individual would not match). It is the probability favoring a random match (the third of these three alternatives) that provides the telling and crucial bottom line of DNA evidence. [20] Cellmark uses the product rule  sometimes called the multiplication rule  to make its random match determination. This rule is described as follows: Suppose, for example, that a pair of DNA [samples] match on two bands, and that one band reflects an allele found in ten percent of the population and the other an allele found in fifty percent of the population. Applying the product rule, an analyst would conclude that the probability of a coincidental match on both alleles is 0.10 X 0.50 = 0.05, or a five percent probability. Thompson & Ford, DNA Typing, 75 Va. L.Rev. at 81-82. [21] The 0.05 result in this example means that there was a one in twenty probability of a random match (leaving a nineteen in twenty chance that the samples came from the same person). The validity, and corresponding accuracy, of the product rule depends on the presence, or absence, of several factors. As applied to this case, the individual frequencies  the necessary components of the product rule (the 0.10 and 0.50 in the example quoted above)  come from, and are based on frequencies in, Cellmark's database. That database apparently bases these frequencies on samples obtained from blood banks as well as paternity and forensic cases. See Pennell, 584 A.2d at 520. These frequency figures  vital components of the product rule  are valid and accurate only if they come from a truly random sample, and the database for the frequency figures must be large enough to be statistically significant. Cauthron, 846 P.2d at 513. [22] The nature of the product rule indicates that any errors, or shortcomings, in the database may have a profound and significant impact on the random match calculations. See Thompson & Ford, DNA Typing, 75 Va.L.Rev. at 81-82. [23] The product rule also is based on the assumption that each band on the autorad represents a DNA segment that is independent of the other bands on the autorad. For this assumption to be valid, the DNA segments tested must be in linkage equilibrium  i.e. the probability of a match on each band is unaffected by the occurrence of a match on any other band. Id. at 81. [24] If this assumption of independence is not correct, the results of the product rule may be incorrect by a substantial margin. [25] A third relevant assumption upon which the product rule is based is a truly random mating population (where mating is random and the gene pool is evenly intermixed). Cauthron, 846 P.2d at 514. Stated very simply, a large, randomly mating population, at least within a generation, is in Hardy-Weinberg equilibrium. See Thompson & Ford, DNA Typing, 75 Va.L.Rev. at 85. As with the other assumptions, if there is no Hardy-Weinberg equilibrium, the product rule results may be incorrect by a substantial margin. See id.
Defense expert Lawrence Mueller, Ph.D., testified that Cellmark's statistical probability calculations were not generally accepted in the relevant scientific community. State expert Dr. Forman conceded that the 1988 Caucasian database used by Cellmark in this case was not in Hardy-Weinberg equilibrium. But see Reporter's Transcript, Mar. 21, 1990, at 5 (contrary testimony by Daniel Garner, Ph.D.). The State argues, however, that Cellmark's calculations resulted in conservative probability figures and were properly admitted. We cannot agree. The admissibility of DNA testing in criminal matters has been litigated for several years. The statistical calculation dispute, however, has not been judicially examined until quite recently. Barney, 10 Cal. Rptr.2d at 743. Many courts have questioned the propriety of DNA statistical probability calculations. See, e.g., Caldwell, 393 S.E.2d at 443; State v. Houser, 241 Neb. 525, 490 N.W.2d 168, 183-84 (1992); People v. Mohit, 153 Misc.2d 22, 579 N.Y.S.2d 990, 998 (Sup.Ct. 1992). Although courts have found DNA testing admissible  explicitly, or more frequently implicitly, finding the probability calculations acceptable  three factors make most of these cases distinguishable. First, in many early cases, the defendant did not challenge the prosecution's evidence. Second, many cases used an admissibility standard less rigorous than Frye and arguably less rigorous than Daubert, basing admissibility on the qualification of experts and relevance. See Anderson, 853 P.2d at 142 (discussing so-called relevancy approach for determining admissibility of scientific evidence). [26] Third, many cases address probability calculations from laboratories other than Cellmark. These laboratories use different databases than Cellmark and, accordingly, these cases may be distinguished. See Anderson, 853 P.2d at 142. Notwithstanding the few remaining cases finding probability statistics admissible, recent developments  scientific and judicial  drastically alter the relevant analysis. Within the last two years, controversy has erupted in the scientific community concerning the reliability of DNA evidence. People v. Atoigue, 1992 WL 245628, at []4 (D.Guam App.Div. Sept. 11, 1992) (emphasis added). A December 1991 edition of Science, a respected scientific journal with articles subject to peer review, contained two articles stating radically conflicting views of statistical probability calculations. Compare R.C. Lewontin & Daniel L. Hartl, Population Genetics in Forensic DNA Typing, 254 Science 1745, 1750 (Dec. 20, 1991) (calculations for the probability of a matching DNA profile ... are unjustified and generally unreliable ) (emphasis added) with Ranajit Chakraborty & Kenneth K. Kidd, The Utility of DNA Typing in Forensic Work, 254 Science 1735, 1739 (Dec. 20, 1991) (method of calculating the probability of a matching DNA profile does not require `fixing' for it to be used in courts). [27] A companion article exclaims that a bitter debate is raging about the courtroom use of DNA testing. See generally Leslie Roberts, Fight Erupts Over DNA Fingerprinting, 254 Science 1721 (Dec. 20, 1991). This companion article describes Lewontin and Hartl as two of the leading lights of population genetics and discusses the pressure brought  by scientists and prosecutors  to include the Chakraborty/Kidd article in response to the Lewontin/Hartl article. Id. [28] These two articles seem likely to reinforce the notion that the [scientific] community is indeed divided. Id. at 1721, 1723. [29] The impact of these articles is best demonstrated by California cases. The California Court of Appeal, in October 1991, rejected a challenge to Cellmark's probability calculations. See Axell, 1 Cal. Rptr.2d at 426-31. The December 1991 Science articles, however, changed this analysis. Just a few months later, the California Court of Appeal said: Whatever the merits of the prior decisions on the statistical calculation process  including Axell  the debate that erupted in Science in December 1991 changes the scientific landscape considerably, and demonstrates indisputably that there is no general acceptance of the current process. It has become irrelevant how Axell addressed this issue at the time of the decision's filing in October 1991. Barney, 10 Cal. Rptr.2d at 744; see also People v. Wallace, 14 Cal. App.4th 651, 17 Cal. Rptr.2d 721, 726-27 (1993) (following Barney ). In Barney, the California Court of Appeal expressly rejected its own precedent and held that the probability analysis, and as a result all DNA identification testimony, was inadmissible. Barney, 10 Cal. Rptr.2d at 745. The California Supreme Court denied review, id. at 731, but expressly authorized publication of the Barney court's DNA discussion, id. at 731 & n. []. [30] Other recent cases confirm this lack of general acceptance of Cellmark's statistical probability calculations in the relevant scientific community of population geneticists. See, e.g., Atoigue, 1992 WL 245628, at []4; Commonwealth v. Lanigan, 413 Mass. 154, 596 N.E.2d 311, 316 (1992); Commonwealth v. Curnin, 409 Mass. 218, 565 N.E.2d 440, 444-45 (1991); State v. Schwartz, 447 N.W.2d 422, 428-29 (Minn. 1989); Vandebogart, 616 A.2d at 493-94; Cauthron, 846 P.2d at 514-17. [31] After reviewing these decisions, as well as recent scientific literature, we agree that the Cellmark method of deriving the random match probability figures is not generally accepted in the relevant scientific community. For Frye purposes, these probability calculations are flawed in three ways: (1) they are impermissibly based on the disputed assumption of linkage equilibrium; (2) the database relied on is of disputed statistical validity; and (3) the database relied on is not in Hardy-Weinberg equilibrium. Given this conclusion, the application of the product rule and the resulting opinion of the odds against a random match were not derived by applying generally accepted scientific theory. [32] We conclude, therefore, that the court erred [33] in admitting the probability testimony based on the product rule calculations. This finding requires us to address one more issue regarding DNA. 6. The effect of the lack of general acceptance of the statistical probability of a random match As the Barney court asked, must the absence of general scientific acceptance as to the current statistical calculation aspect of DNA analysis result in total exclusion of DNA evidence? Barney, 10 Cal. Rptr.2d at 744. Barney stated that, without a determination of the random match probability, a declared match means nothing. Id. at 742. Other courts have agreed. Without the probability assessment, the jury does not know what to make of the fact that the patterns match: the jury does not know whether the [matching] patterns are as common as pictures with two eyes, or as unique as the Mona Lisa. United States v. Yee, 134 F.R.D. 161, 181 (N.D.Ohio 1991), quoted in Anderson, 853 P.2d at 146-47; accord Atoigue, 1992 WL 245628, at []3; see also NRC Summary, DNA Technology at 9. Under ordinary evidentiary principles, these courts conclude that a lack of general acceptance of the random match calculations precludes admission of any DNA evidence. Cauthron went even further. Rather than merely finding that testimony of a match without evidence of the probability of a random match was not helpful to the jury, that court also held that such testimony did not meet the Frye test. Testimony of a match in DNA samples, without the statistical background or probability estimates, is neither based on generally accepted scientific theory nor helpful to the trier of fact. Cauthron, 846 P.2d at 516. Thus, Cauthron found that ordinary evidentiary principles as well as Frye require that a lack of general acceptance for the random match calculations precludes admission of any DNA evidence. A different judicial approach is to uncouple evidence of a match from the random match probability calculations. For example, the court in Pennell found Cellmark's DNA testing and resulting match evidence generally accepted and admissible. Pennell, 584 A.2d at 522. The statistical probability evidence, however, was inadmissible because the state failed to demonstrate a degree of reliability necessary to admit such statistical probabilities. Id. Thus, the jury could hear evidence of the nature of DNA and that a match had been declared, but could not hear evidence of the random match probability. Id. Another approach is to allow expert testimony regarding frequency but not product rule expert testimony. See State v. Johnson, 498 N.W.2d 10, 14-15 (Minn. 1993) (affirming expert testimony that the alleles tested were present in from three to twenty-seven percent of the samples in the FBI's database; the prosecutor's expert properly was not allowed to draw any conclusions from such statistics, nor was he even allowed to speculate [by applying the product rule]). [34] We acknowledge these different approaches to the issue. We also acknowledge that, in this case, the testimony of a match  independent of the probability testimony  unquestionably has relevance to establish one fact: that the blood on Defendant's shirt could have come from the victim (but not that it necessarily and conclusively did come from the victim). This proposition, coupled with general acceptance of the underlying theory of DNA testing, may mean that evidence of a match, accompanied by evidence that a match means that it is possible or probable that the two samples came from the same individual, could be admissible. We need not and do not decide the propriety of such trial strategy because it is not before us. We cannot foresee what explanatory evidence might be available to militate in favor of admissibility of the match evidence independent of the probability calculations. Accordingly, we neither accept nor reject any of the positions taken by other courts on this point. The trial court admitted evidence as to both the declared match and the random match probabilities. We simply hold that statistical evidence of the random match probabilities was inadmissible and, thus, should not have been admitted. We go no further. Thus, we must now determine the effect of the error in admitting such evidence. 7. Was the error in admitting the DNA probability calculations harmless? When an issue is raised but erroneously ruled on by the trial court, this court reviews for harmless error. See State v. McVay, 127 Ariz. 450, 453, 622 P.2d 9, 12 (1980). Absent structural defects, Arizona v. Fulminante, 499 U.S. 279, ___, 111 S.Ct. 1246, 1265, 113 L.Ed.2d 302 (1991), and other matters not subject to harmless error analysis, we use one test to determine whether error is harmless in criminal cases, State v. White, 168 Ariz. 500, 508, 815 P.2d 869, 877 (1991), cert. denied, ___ U.S. ___, 112 S.Ct. 1199, 117 L.Ed.2d 439 (1992); State v. Lundstrom, 161 Ariz. 141, 150 n. 11, 776 P.2d 1067, 1076 n. 11 (1989); State v. Thomas, 133 Ariz. 533, 538, 652 P.2d 1380, 1385 (1982). Error, be it constitutional or otherwise, is harmless if we can say, beyond a reasonable doubt, that the error did not contribute to or affect the verdict. Lundstrom, 161 Ariz. at 150 & n. 11, 776 P.2d at 1076 & n. 11. The inquiry... is not whether, in a trial that occurred without the error, a guilty verdict would surely have been rendered, but whether the guilty verdict actually rendered in this trial was surely unattributable to the error. Sullivan v. Louisiana, ___ U.S. ___, ___, 113 S.Ct. 2078, 2081, 124 L.Ed.2d 182 (1993); accord McVay, 127 Ariz. at 453, 622 P.2d at 14. We must be confident beyond a reasonable doubt that the error had no influence on the jury's judgment. There is no bright line statement of what is and what is not harmless error. See Bush v. State, 19 Ariz. 195, 204, 168 P. 508, 512 (1917); see also Jack B. Weinstein & Margaret A. Berger, 1 Weinstein's Evidence ¶ 103[06], at 103-70 to 81 (1992) (listing factors courts examine in determining whether error was harmless). The State has the burden of convincing us that error is harmless, Chapman v. California, 386 U.S. 18, 24-26, 87 S.Ct. 824, 828-29, 17 L.Ed.2d 705 (1967), and we consider the error in light of all of the evidence, White, 168 Ariz. at 508, 815 P.2d at 877. Due to this case-specific factual inquiry, an error may be harmless in one case but require reversal in another. With these stringent concepts in mind, we assess the record evidence in light of the erroneous admission of the DNA probability calculations. We first note that Defendant challenged the improperly admitted probability evidence at trial. The jury was not left with the impression that the probability calculations were acknowledged as reliable by all scientists. The issue was hard fought. Defense expert Dr. Mueller explained in detail to the jury the lack of Hardy-Weinberg equilibrium, linkage disequilibrium, the possible unreliability of the database, and the consequent misleading end result of the product rule. Dr. Mueller is as well-credentialed and as prominent as Dr. Forman, the prosecution's expert, who presented the opposite view. It is, of course, impossible to know what the jury made of all this, and we assume, as we must, that the jury gave credence to the prosecutor's evidence. Suffice it to say, however, that the picture presented to the jury did not have the aura of infallibility surrounding an unchallenged scientific theory. Rather, the picture portrayed a hotly disputed scientific controversy. If the evidence against Defendant had been closely balanced, strong, or even very strong, we think it would be impossible to say beyond a reasonable doubt that the inadmissible DNA evidence did not affect the verdict. Evidence of odds even as low as one in sixty million that the blood on Defendant's shirt was not the victim's blood is, to say the least, powerful. Factually, however, this is a very unusual case. Given the testimony describing the dispute over the DNA evidence, that evidence was far from the most telling part of the State's case. The other evidence points with unerring consistency to one inarguable conclusion: that Defendant killed the victim. Before Defendant's arrest, the victim's mother described a vehicle matching the GMC that Defendant was driving and placed it where the victim was last seen alive. Her description of the driver was consistent with Defendant. Defendant admitted stealing the GMC before the abduction and was seen driving the vehicle both before and after the abduction. During the relevant time period, no one but Defendant was seen driving the vehicle. Many items connect Defendant and that GMC to the location where the body was found. The rubber bands in the GMC were the same as dozens of rubber bands found in the brush covering the body, near the victim's clothing, and in a tree containing the victim's panties. Before it was stolen, the GMC contained rubber band bags, a rubber band bag was found close to the victim's body, and no rubber band bags were found in the GMC after Defendant's arrest. Investigators found two empty Suntory vodka mini-bottles on Sheep Hill and a twenty mini-bottle container of Suntory vodka, with two bottles missing, in the GMC. The loose packets of hot chocolate in the GMC matched the empty ten-packet box found near the victim's body. The three pieces of metal from the GMC's steering column  one in the GMC, one where the GMC had been parked, and one near the body  fit together like a jigsaw puzzle. A cigar found beside the body matched a cigar in the GMC. Both cigars had similar breaks and were from the same tobacco lot. Tobacco residue from Defendant's shirt was consistent with these cigars. Near the body, investigators found a pubic-type hair similar to Defendant's pubic hair samples. Hair on Defendant's jacket was similar to the victim's, and hair similar to Defendant's was on the victim's T-shirt and the sheet used to wrap the body. Dozens of hairs matching the victim's were located in the GMC, and investigators found hair similar to the victim's on a blanket in the vehicle. When arrested, Defendant possessed knives that, during testing, replicated cuts on the hair found near the body. Fibers near the body were similar to fibers from the seat covers of the GMC, Defendant's jacket, and a blanket found in the GMC. A fiber on the shoelace used to tie the victim's hands was similar to fibers from Defendant's jacket. The blood spatter pattern on Defendant's shirt was consistent with beating force, and investigators found blood-matted grass near the body. Traditional blood testing, unchallenged on appeal, showed that the blood on Defendant's shirt was PGM 2 subtype  the same subtype as the victim's blood. Less than three percent of the population has PGM 2 subtype, and Defendant could not be the source of this blood. In sum, the properly admitted evidence in this case goes far beyond overwhelming evidence of guilt. It is not only inconsistent with any reasonable hypothesis of innocence, it refutes any hypothesis other than Defendant's guilt. It is simply inconceivable that anyone other than the person who had the GMC perpetrated the crime. Nothing else explains the rubber bands, rubber band bag, vodka bottles, hot chocolate packets and container, cigars, and metal pieces from the steering column. There is no question that Defendant possessed the vehicle and no evidence that anyone else possessed the GMC during the relevant time period. Even if one were inclined to speculate about who controlled the vehicle, there is the evidence  fibers, hair, blood, and knives  tying Defendant to the vehicle, to the victim, to the crime scene, and to the crime. Defendant advances no theory of how all this could be explained unless Defendant, and only Defendant, committed the crime. Given this unequivocal evidence, independent of the hotly contested DNA probability evidence, we find beyond a reasonable doubt that the erroneous admission of the DNA evidence could have had no influence on the verdict of [this] jury. McVay, 127 Ariz. at 453, 622 P.2d at 14. Other courts have reached similar conclusions with weaker, or at least comparably strong, evidence of guilt independent of the erroneous admission of DNA evidence. See, e.g., Barney, 10 Cal. Rptr.2d at 747-48 (upholding conviction where defendant's wallet found on bloodstained couch in victim's home, defendant's fingerprint found in room of victim's home, and non-DNA blood testing linked defendant to crime scene); State v. Nielsen, 467 N.W.2d 615, 619 (Minn. 1991) (victim last seen alive with defendant, blood matching victim's found on defendant's shirt, untypable human blood found in defendant's car, defendant's blood type matched semen found on victim's body, defendant had black eye day after murder, and defendant left the area when told that the police were looking for him); cf. Wallace, 17 Cal. Rptr.2d at 726-27 (following Barney and upholding conviction where crimes were distinctive, one victim identified defendant, circumstantial evidence connected defendant to crimes, traditional blood typing eliminated all but two or three percent of the population, and defendant admitted committing offenses to fiancee); Atoigue, 1992 WL 245628, at []4 (upholding conviction where victim identified defendant). But see Houser, 490 N.W.2d at 184 (Reception of the DNA evidence cannot be said to be harmless error.) (citing cases). Again, we emphasize that we do not, and cannot, find harmless error based on our idea of guilt or innocence or whether there is sufficient proper evidence to convict. See, e.g., Sullivan, ___ U.S. at ___-___, 113 S.Ct. at 2081-82; McVay, 127 Ariz. at 453, 622 P.2d at 12. We cannot and do not speculate as to what a reasonable jury would have done. See Sullivan, ___ U.S. at ___-___, 113 S.Ct. at 2081-82. We are convinced beyond a reasonable doubt, however, that the guilty verdict in this case was unaffected by the improper admission of the DNA evidence. Thus, because the State has carried its heavy burden, we hold that the error in admitting the probability evidence was harmless. 8. Summary regarding DNA evidence To summarize, we hold that the principles and theory underlying DNA testing and Cellmark's match criteria are generally accepted in the relevant scientific community. General acceptance regarding these matters permits judicial notice of DNA theory and the techniques  at least insofar as Cellmark is concerned  for ascertaining and declaring a match. From this point forward, Arizona trial courts no longer need to hold Frye hearings regarding the general acceptance of DNA theory, the principles underlying DNA testing, or the Cellmark match criteria. We emphasize, however, what this means and what it does not mean. If testing shows that samples do not match, then the conclusion is that they are from different individuals. If testing shows that the samples do match, the conclusion is that they may be from the same individual. We conclude that there is no general acceptance in the relevant scientific community for Cellmark's random match probability calculations. Because these calculations do not meet the Frye test, they are inadmissible. We reserve and expressly do not decide whether the inadmissibility of the random match probability calculations means that other DNA evidence, such as evidence of a match, is inadmissible. Finally, on the unique facts of this case, we hold that the admission of the inadmissible DNA probability evidence was harmless error. We take a cautious, conservative approach. Not knowing what records in other cases will show, what issues those cases will raise, or what new technology will bring, we neither write in stone nor go farther than we must. For the moment, and at least with respect to DNA evidence, we leave Frye untouched. We make no final judgment on how far, if at all, the court may go in allowing a party to inform the jury about the declaration of a match and its meaning in any specific case. We hold only that statistical probability evidence based on Cellmark's database is not based on generally accepted scientific theory and is not admissible.