Can DNA evidence be excluded based on chain of custody issues? Griffin v. State Explained

In Griffin v. State, the Utah Supreme Court addressed significant challenges to DNA evidence in a decades-old murder case, ultimately affirming that even imperfect chain of custody does not automatically exclude critical genetic evidence.

Background and Facts

In 1984, Bradley Perry was brutally murdered while working at a Texaco gas station. Two college students encountered a suspicious man at the station shortly after the crime and received bloody dollar bills from him. The case went cold until 2005, when DNA testing matched blood on one of the dollar bills to Glenn Griffin. Additional mitochondrial DNA testing of hairs from the crime scene could not exclude Griffin as a contributor. Griffin was convicted of murder and sentenced to life without parole.

Key Legal Issues

Griffin challenged the admissibility of both the nuclear DNA blood evidence and mitochondrial DNA hair evidence on multiple grounds. He argued that gaps in the chain of custody made the evidence inadmissible, that foundational evidence violated hearsay rules and his confrontation clause rights, and that the statistical testimony about DNA frequency was unreliable. Griffin also claimed his counsel was ineffective for failing to challenge the DNA evidence more aggressively.

Court’s Analysis and Holding

The court applied established Utah precedent requiring that evidence be in “substantially the same condition” when introduced as when the crime was committed. Importantly, the State need not “eliminate every conceivable possibility” of alteration. Instead, once evidence is in state custody, there is a presumption of regularity absent affirmative proof of tampering or bad faith.

The court found Griffin had merely identified “weak links” in the chain of custody but failed to prove actual contamination. While Detective Beard’s field notes were used to establish foundation, this did not violate evidence rules because Rule 104(a) permits consideration of otherwise inadmissible evidence when determining preliminary admissibility questions.

Practice Implications

This decision reinforces that chain of custody challenges require more than speculation about possible contamination. Practitioners must develop evidence of actual tampering or bad faith to overcome the presumption of regularity. The court’s analysis also demonstrates that even decades-old evidence can be admitted if properly authenticated, making thorough investigation of handling procedures critical in cold cases involving DNA evidence.