Opinion ID: 1657195
Heading Depth: 1
Heading Rank: 8

Heading: Band Shifting Correction

Text: The defendant acknowledges that DNA profiling in general and RFLP analysis are admissible, but argues that the specific method employed by Lifecodes to correct for band shifting is unreliable because there is no scientifically accepted protocol of how to adjust the bands. [8] Dr. McElfresh testified, at the admissibility hearing and at trial, that band shifting is a common phenomenon in DNA analysis. He explained that Lifecodes uses monomorphic probes, a method of correction which allows the technician to resituate the bands where they would have appeared had they not shifted. Dr. McElfresh maintained that, using this method, the laboratory can still declare a match where band shifting had occurred. Following the trial court's ruling allowing the state to present the expert scientific testimony, Dr. McElfresh and Forensic Scientist Vining testified to the jury that Lifecodes declared a match between the defendant's DNA imprint and the seminal fluid found on the towel near the victim's leg even though the autorad showed evidence of band shifting. Dr. McElfresh testified that Lifecodes is the only laboratory which attempts to correct for band shifting and still declare a match. He maintained that the correction procedure was valid and reliable, and reviewed by the scientific community. As of the date of the trial, Lifecodes had submitted one paper for publication in The Journal of Forensic Science on the use of monomorphic probes to correct for band shifting. That paper had not yet been published and was undergoing peer review. The defendant's experts, Drs. Cohen and Jazwinski, disputed Lifecodes' claims in their testimony before the jury. Dr. Cohen testified that there was no way to correct for band shifting and that generally scientists disregarded such results. He remarked that he was extremely disturbed that Lifecodes independently created a correction factor their own personal fudge factor that no one else accepts, noting it had not even been documented. Dr. Cohen observed that without the correction some of the bands in this case would be outside of Lifecodes' match criterion of 2% deviation. Dr. Jazwinski further informed the jury that no valid methods existed to correct the bands and that Dr. McElfresh's claim that Lifecodes' method had been peer reviewed was unfounded. The defendant cites jurisprudence from other jurisdictions which has applied the general acceptance Frye standard, and has deemed inadmissible DNA results which have employed correction for band shifting. [9] In addition, defendant points to the findings stated in DNA Technology in Forensic Science, National Research Council, National Academy Press (1992). [10] The NRC report, which was not available at the time of trial in 1990, provides an in-depth analysis of the forensic use of DNA evidence and associated areas, including band shifting. Although we need not rely upon the conclusions of the report in deciding the assignment of error presented in this case, the report is nevertheless illustrative of the issue. The NRC directly addresses the problem of band shifting as follows: Testing for band shifting is easy, correcting for it is harder. The best approach is to clean the samples ... and repeat the experiment in the hope of avoiding band shifting. When that is impossible because too little sample is available or it fails ..., it is possible in principle to determine the molecular weights of polymorphic fragments in a sample by comparing them with monomorphic human bands in the same laneso called internal molecular weight standards. These monomorphic fragments are expected to have undergone the same band shift, so they should provide an accurate internal ruler for measurement.... In practice, however, the use of internal standards presents serious difficulties. Accurate size determination requires a number of internal standards. If band shifting caused all fragments to change their mobility by the same percentage, one would need only a single monomorphic fragment to determine the extent of shift. But band shifting appears to be more complex than that. Different regions of the gel shift by different amounts. Little has been published on the nature of band shifting, on the number of monomorphic internal control bands needed for reliable correction, and on the accuracy and reproducibility of measurements made with such correction. For the present, several laboratories have decided against attempting quantitative corrections; samples that lie outside the match criterion because of apparent band shifting are declared to be inconclusive. The committee urges further study of the problems associated with band shifting. Until testing laboratories have published adequate studies on the accuracy and reliability of such corrections, we recommend that they adopt the policy of declaring samples that show apparent band shifting to be inconclusive.