Opinion ID: 1873955
Heading Depth: 1
Heading Rank: 4

Heading: Prong III: Performance and interpretation of accepted techniques.

Text: The third prong asks: In this particular case, did the testing laboratory perform generally accepted scientific techniques without error in the performance or interpretation of the tests? In order to answer this question, we must make two inquiries. First, were the techniques used by the testing laboratory generally accepted in the scientific community? Second, was there error in the performance or interpretation of the tests? Regarding the first inquiry, we recognize and are almost persuaded by the holdings in other cases that have involved the question whether Lifecodes' techniques are generally accepted in the scientific community. In each instance, Lifecodes' techniques were held to be generally accepted in the scientific community. Caldwell; Ford; Castro; Spencer; Andrews. The record before us does not support such a holding, however. Apart from specific testimony on the Southern transfer portion of the procedures used by Lifecodes (step 4 in the description of DNA analysis, supra), Squeglia and Dr. McElfresh testified in a limited, conclusory manner that the techniques they used were generally accepted in the scientific community. Considering the import of this issue, we will not hold that that testimony of Squeglia and Dr. McElfresh, who both have an obvious interest in validating Lifecodes' techniques, was sufficient to support a holding that those techniques are generally accepted in the scientific community. We note that if in the future it is proved to this Court that certain techniques are generally accepted in the scientific community and then those same techniques are exclusively used in other cases, it may be possible to hold as a matter of law that the techniques are generally accepted in the scientific community. The evidence in the record before us is not sufficient for us to determine whether there was error in the performance or interpretation of the tests. [1] Perry cross-examined Dr. McElfresh on this issue, but Perry did not provide his own evidence to establish that there was error in the performance or the interpretation of the tests. The cases that we have discussed in relation to other issues of admissibility strongly suggest that DNA evidence can meet every other requirement of admissibility but nevertheless fail on this requirement. Caldwell; Ford; Castro; Schwartz; Pennington; Two Bulls. Caldwell and Castro exemplify this. In Caldwell, the Supreme Court of Georgia addressed a defendant's concerns [about] Lifecodes' quality control [and] the manner in which it declares a `match.' 260 Ga. at 279, 393 S.E.2d at 437. Addressing those concerns, the court wrote: The dispute centers on the techniques and procedures followed (or not followed) by Lifecodes in this case. Initially, then, we need to decide whether such concerns go merely to weight or whether they implicate admissibility also. We recognize that, while the DNA identification procedures and technology used in this case have been widely used in laboratories for years in experimental and diagnostic settings, the transfer of this technology to a forensic setting is comparatively recent. As noted previously, there are three private laboratories in this country doing forensic DNA analysis. One of them uses procedures entirely different from those explained above (and the record in this case does not explain what those procedures are). The other two use essentially the same technology, but their protocols are different, and they use different restriction enzymes and different probes. The FBI has recently set up its own forensic DNA lab, using still different restriction enzymes and probes. One consequence of this is that the database generated by each system for use in probability analysis is unusable by the other laboratories. In other respects, there may be disagreements at present about, for example, what is a match. Because of `band shift,' two lanes of identical samples may not run exactly the same, raising questions such as: How much variation can exist before a match is not a match? What tests, if any, should be run to determine whether a difference in the pattern on two lanes of an autoradiograph is due to band shift? In light of the novelty of the use of DNA analysis in forensics, the complexity of the tests, and the present lack of national standards governing such tests, we conclude the trial court was correct when it determined not just whether the general scientific principles and techniques involved are valid and capable of producing reliable results, but also whether Lifecodes substantially performed the scientific procedures in an acceptable manner. Compare [ State ] v. Schwartz, 447 N.W.2d 422, 428 (Minn. 1989); People v. Castro, 545 N.Y.S.2d 985 (Sup.Ct.1989). We believe this approach is consistent with Harper v. State, supra, 249 Ga. [519] at 524-526, 292 S.E.2d 389 [(1982)]. This does not mean that the trial court must exclude novel scientific evidence unless convinced there is no possibility of error. No procedures are infallible. If, for example, a sample was accidentally mislabelled, and the laboratory compared two samples from the same source believing it was comparing a sample of evidence with a sample from the defendant, the result would be a false match. Or, if the laboratory mistakenly or carelessly added sample material from the defendant to the evidentiary sample, and the evidentiary sample was very degraded, leaving no bands on the autoradiograph, the bands from the defendant's sample in evidence lane would match the bands in the lane assigned the defendant's sample, and, again, a false match would occur. Obviously, a laboratory needs to take precautions at all stages of its testing procedures. The defendant's experts testified about various ways that errors conceivably could occur, including mislabelling and crossmixing of samples, bacterial contamination, less than perfect chemical preparations, and so forth. We agree with the trial court's assessment that Lifecodes' protocol is adequate to meet these concerns. More significant were criticisms about: (1) the manner in which a match was declared; (2) Lifecodes' failure (initially) to test for band shift; and (3) the probability estimates. 260 Ga. at 286-87, 393 S.E.2d at 441-42. The court ultimately concluded that in Caldwell Lifecodes' declaration of a match was proper. 260 Ga. at 288-89, 393 S.E.2d at 443. In Castro, the court held a portion of the DNA evidence admissible and a portion inadmissible because Lifecodes, the testing laboratory, had made errors in the performance of the tests. The court discussed potential problems with the performance and interpretation of DNA tests: When scientists use Southern Blots for clinical or diagnostic purposes they use fresh or dried blood samples from a known source. Thus, if a particular experiment gives an uninterpretable result, the scientist need only obtain more blood from the patient and re-perform the experiment. In forensic cases, however, the samplesay a blood stain found at a crime scene, or a semen sample obtained from a rape victimis limited. If the experiment goes awry, there is no way to redo it. Thus, for forensic purposes, there is only one bite of the apple. The forensic scientist must take special pains to be sure that proper controls were utilized to ensure that the experiment was performed correctly. Additionally, forensic samples are frequently contaminated by material which mixes with the blood at the scene, or by bacteria which grows in the sample. If these contaminants contain DNA, that DNA will show on the autoradiograph along with the human DNA. Thus, the forensic scientist must also have a method for determining which DNA is human and which DNA is nonhuman. Unlike the clinical scientist who can simply obtain more sample which is uncontaminated, the forensic scientist must make the best interpretation possible with what is available. The forensic scientist also faces problems in interpreting the autoradiograph which clinical scientists do not. The clinical scientist knows who the subject is and can obtain blood samples from the subject's parents. Thus, the clinical scientist can run lanes of the subject's parents' DNA alongside that of the subject. This procedure allows for relative certainty in measuring the kilobase size of a given allele. Since the allele in question must have been transmitted to the subject by one of the parents, a comparison of the three DNA samples can resolve ambiguities about whether one allele in fact matches another. The forensic scientist does not have this luxury. The forensic sample comes from an unknown source whose parent can be anybody in the world. Thus, the forensic scientist must use other means to resolve ambiguities, or face the fact that the autoradiograph is uninterpretable and the evidence is rendered worthless. 144 Misc.2d at 969-70, 545 N.Y.S.2d at 993-94. Finally, in regard to whether there was error in the performance or interpretation of the tests, we note that this challenge to admissibility will be available even if the challenge under the first portion of the third prong is determined as a matter of law. To summarize our discussion of the third prong of the admissibility test, we hold that the evidence in the record before us is insufficient for us to determine whether there was error under either of the two inquiries that must be addressed in the third prong of the analysis. As in the preceding sections, we do not address our discussion in this section to the DNA population frequency statistical evidence.