People v. Bullard-Daniel
2016 NY Slip Op 26313
New York County Court, Niagara...2016Background
- Defendant charged with predatory sexual assault (Penal Law § 130.95[1][a]) and first-degree burglary; prosecution intended to introduce DNA evidence and STRmix-generated likelihood ratios.
- Erie County Forensic Lab performed STR analysis on crime-scene items and a red-stained sock from defendant’s bedroom; Lab began using STRmix in July 2015.
- Defense sought a Frye hearing challenging admissibility of STRmix-based probabilistic genotyping and related expert testimony; court held a multi-day Frye hearing.
- People’s sole live witness: Dr. John Simich (Lab director/DNA technical leader) who testified to STRmix validation, Lab internal validation, and Commission/DNA Subcommittee approval.
- Defense’s witness: Dr. Gary Skuse (bioinformatics) criticized human intervention, variability between runs, and objectivity; conceded limited forensic-DNA experience and no STRmix use.
- Court evaluated general acceptance under Frye, considered Lab validation, peer-reviewed literature, Commission/DNA Subcommittee approvals, and existing case law on probabilistic genotyping.
Issues
| Issue | People’s Argument | Defendant’s Argument | Held |
|---|---|---|---|
| Whether STRmix probabilistic genotyping is generally accepted in the relevant scientific community (Frye admissibility) | STRmix implements accepted probabilistic genotyping, validated internally and externally; recommended by SWGDAM/NIST and approved by NY DNA Subcommittee/Commission; used by several labs | STRmix not generally accepted; community is insular and biased toward prosecution; software involves subjective inputs and yields variable LR results across runs | Admissible: court finds general acceptance by preponderance of evidence and admits STRmix-based results |
| Reliability of STRmix validation and Lab implementation | Lab performed internal validation, followed SWGDAM guidance; external audits and accreditation support reliability | Validation tautological and insufficient; variability across runs undermines objectivity and reproducibility | Validation adequate for Frye; variability noted but goes to weight, not admissibility |
| Weight vs admissibility of probabilistic LR results | Statistical evaluation affects evidentiary weight, not admissibility | Variability and human choices in setup affect fundamental reliability and should bar admissibility | Court treats statistical nuances as matters for cross-examination and jury weight, not Frye exclusion |
| Role of NY Commission/DNA Subcommittee approvals in Frye analysis | Subcommittee/Commission approval evidences general acceptance and carries significant weight | Such institutional approval may be insufficient to establish community-wide acceptance | Court gives substantial weight to Subcommittee/Commission approvals in finding general acceptance |
Key Cases Cited
- Frye v. United States, 293 F. 1013 (D.C. Cir. 1923) (establishes general-acceptance standard for novel scientific evidence)
- People v. Hughes, 59 N.Y.2d 523 (N.Y. 1983) (New York Frye framework and sources of proof for scientific acceptance)
- People v. Wesley, 83 N.Y.2d 417 (N.Y. 1994) (court should determine general acceptance within the relevant scientific community)
- People v. Wakefield, 47 Misc. 3d 850 (N.Y. Sup. Ct. 2015) (upheld probabilistic genotyping—TrueAllele—finding general acceptance and superiority over qualitative methods)
- People v. Collins, 49 Misc. 3d 595 (N.Y. Sup. Ct. 2015) (contrasting decision that more skeptically weighed validation and expert dissent in evaluating genotyping software)