Legal trends in the admissibility of forensic evidence. (Paul Giannelli, Case Law School)

1. Mitochondrial: United States v. Beverly, 369 F.3d 516, 531 (6th Cir. 2004).

2. Nonhuman DNA evidence. United States v. Boswell, 270 F.3d 1200 (8th Cir. 2001) (in a false statement prosecution, DNA used to compare swine blood); State v. Bogan, 905 P.2d 515 (Ariz. Ct. App. 1995) (in murder case, DNA of seed pods from palo verde trees at scene compared to those found in Bogan's truck); State v. Schmidt, 699 So. 2d 448 (La. Ct. App. 1997) (in attempted murder by injection of HIV virus, expert testified that HIV from two persons were "closely related"). But see State v. Leuluaiaii, 77 P.3d 1192 (Wash. App. 2003) (canine DNA match between sample obtained from defendant and murder victim's dog not generally accepted).

3. DNA evidence without corroboration. In State v. Toomes, 191 S.W.3d 122, 131 n.5 (Tenn. Crim. App. 2005), the court upheld a conviction based DNA alone but with a caution: "By our holding, we are not announcing an iron-clad princip[le] that DNA evidence, without corroboration, is always sufficient to support a conviction. Practically infinite factual variations can arise, and we do not intend by our opinion to prejudge other factual scenarios. For instance, this case has an unusual feature in that two separate DNA comparisons were performed. The first comparison identified the twin's DNA, and the second comparison identified the twin's and the defendant's DNA, which were identical, thereby reinforcing the integrity of the comparisons. In our opinion, it is quite sufficient in this case to recognize and respect the admissibility of DNA evidence and to conclude that the evidence was sufficient to support the defendant's aggravated rape conviction."

4. Testimony without statistics? Young v. State, 879 A.2d 44, 56-57 (Md. 2005) ("[T]here exist methods of DNA analysis employing certain markers that, when tested along a minimum number of loci, yield DNA profiles with an astonishingly small random match probability. When the random match probability is sufficiently minuscule, the DNA profile may be deemed unique. In such circumstances, testimony of a match is admissible without accompanying contextual statistics. In place of the statistics, the expert may inform the jury of the meaning of the match by identifying the person whose profile matched the profile of the DNA evidence as the source of that evidence; i.e. the expert may testify that in the absence of identical twins, it can be concluded to a reasonable scientific certainty that the evidence sample and the defendant sample came from the same person.").

5. Statistics in cold hit cases. See People v. Johnson, 43 Cal. Rptr. 3d 587(Cal. App. 2006) ("[T]he fact that many profiles have been searched increases the probability of finding a match, so that conceptually, the more populated the database, the less impressive the match. Appellant contends that there is broad scientific consensus concerning the need to determine differently the statistical significance of profile matches in a cold hit case versus a confirmation case, but says that the means of determining the statistical value of a cold hit 'is a matter of continuing and strident debate.' ").

6. Population groups. People v. Wilson, 45 Cal. Rptr. 3d 73, 81 ( Cal. 2006) ("By presenting the data for the major racial components of the population, when there is no independent evidence of the perpetrator's race, the prosecution presents the data necessary for the jury to evaluate the likelihood that the crime scene DNA came from someone other than the defendant. Presenting the objective data in the manner in which such information is collected and analyzed within the scientific community does not inject inappropriate racial assumptions or issues into the litigation. To the contrary, in presenting data for the most numerous racial groups in the population, the focus is removed from the race of the defendant.' ").

Materials

Presentation

Last modified: 03/12/10