2013 COA 161
Colo. Ct. App.2013Background
- Victim was sexually assaulted in her home; William Anthony Tunis was charged, tried, and convicted of sexual assault and second-degree burglary and sentenced to 12 years to life, with a sexually violent predator (SVP) designation.
- Identification at trial relied on victim testimony and DNA evidence, including Y‑STR analysis from a mixed male/female sample recovered from the victim's inner thigh; a partial Y‑STR profile (7 of 17 loci) matched Tunis.
- The CBI analyst used the YFiler database (about 8,561 profiles) and the counting method to estimate exclusion percentages (≈99%+ by major racial groups); assay used ~0.8 ng of DNA and a 3:1 peak ratio rule to call major/minor contributors.
- Pretrial Shreck hearing admitted the Y‑STR evidence under CRE 702/403; analyst was qualified and court found methodology and statistics sufficiently reliable and not unfairly prejudicial.
- During trial a juror was repeatedly observed nodding off and was replaced with an alternate; defendant moved for mistrial alleging prejudice from the replacement.
- After sentencing the court designated Tunis an SVP under §18‑3‑414.5, relying on findings that he "promoted a relationship primarily for the purpose of sexual victimization." The court of appeals reconsidered the SVP finding in light of People v. Gallegos.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility/reliability of Y‑STR evidence | Y‑STR is methodologically similar to autosomal STRs; expert qualified; database/counting method and lab practices reliable | Y‑STR unreliable due to partial profile, small database, low DNA amount, and analyst discretion in mixture interpretation | Admitted: no abuse of discretion. Expert qualified; 3:1 major/minor rule, database size, counting method, and amount (.8 ng) were sufficiently reliable under CRE 702. |
| Replacement of sleeping juror | Court acted properly to preserve trial integrity; alternate was acceptable | Dismissal denied right to particular juror and alternate was biased favoring DNA | No abuse of discretion. Dismissal/replacement appropriate; defendant failed to show actual prejudice or bias. |
| SVP designation based on "promoted a relationship" | Screening-in findings supported designation | Designation improperly relied on conduct during the assault (and other insufficient facts); Gallegos excludes conduct "during the commission" from promoting-a-relationship analysis | SVP designation vacated. Court's findings relied on conduct during the assault and other insufficient inferences; remand limited to correcting mittimus to remove SVP label. |
Key Cases Cited
- People v. Shreck, 22 P.3d 68 (Colo. 2001) (framework for admissibility of scientific expert evidence under CRE 702/403)
- People v. Gallegos, 307 P.3d 1096 (Colo. 2013) (definition/limits of "promoted a relationship" for SVP determinations)
- People v. Rector, 248 P.3d 1196 (Colo. 2011) (standard of review for admission of expert testimony)
- People v. Wilkerson, 114 P.3d 874 (Colo. 2005) (separate reliability analysis for statistical/numerical evidence under CRE 702)
- Golob v. People, 180 P.3d 1006 (Colo. 2008) (liberal standard for qualifying experts under CRE 702)
- People v. Tixier, 207 P.3d 844 (Colo.App. 2008) (examples of conduct showing "promoted" a relationship)
- Daubert v. Merrell Dow Pharm., 509 U.S. 579 (1993) (factors for scientific evidence reliability cited in admissibility analysis)