State v. Simmer, 935 N.W.2d 167

In 2007 Joy Blanchard was murdered; investigators swabbed the crime scene (knife handles, a broken spindle, interior doorknob) for DNA.
UNMC testing (2015–2016) identified mixed male Y-STR profiles on the knife and spindle (Simmer and/or his brother could not be excluded) and an autosomal mixture on the doorknob that included Simmer.
The State used Cybergenetics’ TrueAllele probabilistic genotyping (Perlin) to analyze the low‑quantity/mixed samples; TrueAllele produced likelihood ratios: ~3.71×10^3 for the knife and ~4.22×10^18 for the doorknob.
Simmer moved in limine under Daubert/Schafersman to exclude TrueAllele evidence, arguing general unreliability and case‑specific application problems (lack of software‑engineering validation, no independent source‑code review, and limits identified in some external reports).
After evidentiary hearings (testimony from UNMC analyst Helligso, Perlin for Cybergenetics, and defense consultant Adams), the district court admitted the TrueAllele evidence; Simmer was convicted and appealed on the sole ground of evidentiary admission.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Admissibility of TrueAllele under Daubert/Schafersman (general reliability)	Simmer: TrueAllele lacks adequate validation from a software‑engineering perspective; source code not independently reviewed; Perlin has financial interest in results.	State: TrueAllele rests on established math (Bayesian/MCMC), complies with SWGDAM guidance, backed by 34 validation studies and peer‑reviewed publications, and enjoys broad practical acceptance.	Court: Affirmed admission — district court did not abuse discretion; validation studies, peer review, SWGDAM compliance, and practical use supported reliability.
Application of TrueAllele to this case (mixture weights/low minor contributor)	Simmer: External reports (Virginia study; PCAST) show limitations for low minor‑contributor weights (knife minor contributor ~2%), so TrueAllele is unreliable here.	State: The cited studies either do not apply (Virginia study addressed 3‑person mixes), were not in the record (PCAST not in record), and TrueAllele’s output reflects reduced certainty for low mixture weight (properly considered in LR).	Court: No abuse of discretion — the studies did not show TrueAllele unreliable for the facts here; any reduced certainty was a weight issue for the jury, not a bar to admissibility.

Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579 (U.S. 1993) (trial‑court gatekeeping for scientific evidence; factors for assessing reliability).
Schafersman v. Agland Coop, 262 Neb. 215 (Neb. 2001) (adopting Daubert framework in Nebraska and permitting re‑examination of previously admitted scientific evidence).
Kumho Tire Co. v. Carmichael, 526 U.S. 137 (U.S. 1999) (Daubert reliability inquiry is flexible and applies to all expert testimony).
State v. Tucker, 301 Neb. 856 (Neb. 2018) (standard of review for admissibility of expert testimony: abuse of discretion).
State v. Casillas, 279 Neb. 820 (Neb. 2010) (burden on proponent to establish admissibility under Daubert/Schafersman).