State v. Gomez
226 Ariz. 165
| Ariz. | 2010Background
- Gomez was charged with home-invasion-related offenses and DNA from crime-scene items and Gomez’s blood was analyzed in a laboratory.
- The lab used a multi-step, mostly machine-driven process; technicians performed initial screening and data generation, while the final interpretation step was done by a single analyst.
- Several technicians who performed earlier steps did not testify; only the supervising analyst testified about procedures, safeguards, and chain of custody.
- The analyst testified that multiple crime-scene DNA profiles matched Gomez’s profile, but the data were not entered as exhibits.
- Gomez was convicted; the appellate court affirmed, and the Arizona Supreme Court granted review to address Confrontation Clause concerns in this context.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Does DNA-profile testimony violate Confrontation Clause when non-testifying technicians generated the data? | Gomez argues non-testifying technicians’ data are hearsay via machine-generated profiles. | Gomez contends absence of technicians in cross-examination violates confrontation rights. | No, testimony by a knowledgeable analyst suffices; no violation. |
| May an expert base an opinion on data from non-testifying sources without violating the Confrontation Clause? | Gomez argues the analyst is a conduit for others’ findings. | Gomez contends reliance on non-testifying data should be barred. | Yes; the analyst formed independent conclusions based on data routinely relied upon by experts. |
| Is a limiting instruction under Rule 105 required when non-testifying data underpin expert opinion? | Gomez requested a limiting instruction to restrict use of non-testifying data. | Court need not give limiting instruction because data were not admitted as exhibits. | No reversible error; instruction not required since profiles were not admitted as evidence. |
Key Cases Cited
- Crawford v. Washington, 541 U.S. 36 (2004) (established testimonial nature of out-of-court statements)
- Melendez-Diaz v. Massachusetts, 557 U.S. 250 (2009) (forensic affidavits are testimonial; confrontation required)
- Pendergrass v. State, 913 N.E.2d 703 (Ind. 2009) (laboratory supervisor testimony can support DNA conclusions)
- Snelling v. State, 225 Ariz. 182 (Ariz. 2010) (expert may rely on data from others if not a conduit for non-testifying findings)
- Bullcoming v. New Mexico, 131 S. Ct. 2705 (2011) (live testimony by a qualified analyst can satisfy confrontation)