NCJ Number
189669
Journal
Crime Victims Report Volume: 5 Issue: 2 Dated: May/June 2001 Pages: 19-21,30
Date Published
2001
Length
4 pages
Annotation
This second part of a two-part series on the admissibility of DNA evidence discusses the admissibility of mitochondrial DNA (mtDNA), which is found in mitochondria, organelles contained within the cytoplasm of a cell and serve as the cell's energy factories.
Abstract
Unlike nucleus DNA that contains genetic material inherited from both the mother and the father, mtDNA only contains genetic material inherited from the mother. Two advantages of mtDNA are that there are many more copies of mtDNA in the cell than there are copies of nuclear DNA, since each cell contains many mitochondria but only one nucleus, and mtDNA is much more stable than nuclear DNA. In the case study presented in this article, the trial judge found mtDNA evidence to be admissible, and the defendant was found guilty based largely on the mtDNA analysis of hair and semen found at the murder scene. The defendant appealed his conviction [South Carolina v. Council (1999)], claiming among other things that the trial judge erred in admitting mtDNA evidence at trial. Council's attorneys argued that the forensic application of the mtDNA testing process had not yet gained general acceptance in the scientific community. In affirming the reliability of the evidence, the appeals court referred to the expert testimony presented at the trial and findings of the trial court. This article also examines mtDNA issues in Tennessee v. Scott (1999). Scott argued on appeal that the trial court denial of expert assistance in the field of DNA analysis to obtain instruction on the underlying methodology of DNA testing and the appropriate potential lines of questioning deprived the defendant of the process and effective assistance of counsel. The appeals court affirmed the trial court's determination, referring to a U.S. Supreme Court decision that enumerated the relevant factors in determining whether an individual defendant is entitled to services. Scott also argued that the trial court denied him due process by failing to conduct a pretrial hearing on the admissibility of mtDNA evidence. In affirming the ruling of the trial court, the appeals court gave a short history lesson on the admissibility of scientific evidence at criminal trials.