Can Utah courts admit testimony about witness confidence in eyewitness identification? State v. Guzman Explained

In State v. Guzman, the Utah Court of Appeals addressed whether courts may admit testimony about a witness’s confidence in eyewitness identification, clarifying the distinction between constitutional admissibility standards and jury credibility determinations.

Background and Facts

Following a home invasion robbery, the victim identified Guzman as the gunman from photo arrays and a lineup. During pretrial identification procedures, she rated her confidence as “10” on a scale of one to ten and stated she was “100 percent positive.” Guzman moved to exclude testimony about the victim’s confidence level, arguing that certainty has no correlation with accuracy and should be deemed inherently unreliable. The trial court denied the motion, and Guzman was convicted of aggravated robbery and aggravated kidnaping.

Key Legal Issues

The primary issue was whether admitting testimony about witness confidence in eyewitness identification violates due process under Utah and federal constitutional standards. Guzman also argued the testimony violated Utah Rule of Evidence 403 because its prejudicial effect substantially outweighed its probative value.

Court’s Analysis and Holding

The court distinguished between the judge’s role in determining constitutional admissibility and the jury’s role in weighing credibility. Under federal analysis following Neil v. Biggers, certainty is specifically recognized as a valid reliability factor. Under Utah’s more stringent Long factors analysis, the court confirmed that while certainty is not considered in determining constitutional reliability for admissibility purposes, it remains relevant evidence for jury consideration once identification testimony is properly admitted.

The court rejected Guzman’s argument that certainty testimony must be wholly excluded, explaining that such testimony can assist juries in evaluating credibility and determining appropriate weight. The court also found no Rule 403 violation, noting the presumption favoring admissibility.

Practice Implications

This decision reinforces that practitioners challenging eyewitness identification should focus on the Long factors for constitutional reliability rather than seeking broad exclusion of certainty testimony. Defense attorneys should recognize that juries remain entitled to consider witness confidence as one factor in credibility assessment. When representing the state, prosecutors may introduce witness confidence testimony as probative evidence, though they should be prepared to address challenges based on the distinction between admissibility standards and credibility factors.