Can police officers testify about alcohol burn-off rates without scientific expertise? State v. Harvey Explained

In State v. Harvey, the Utah Court of Appeals addressed whether a police officer can testify as an expert about alcohol burn-off rates based solely on general training received at the police academy. The court’s decision provides important guidance on the foundational requirements for expert testimony in DUI cases.

Background and Facts

Harvey was arrested for DUI after an officer observed signs of alcohol consumption and administered field sobriety tests. His blood was drawn two hours after the traffic stop, showing a BAC between .075-.081. At trial, the officer testified that “the average burn-off rate [for alcohol] is approximately .015” per hour, stating he learned this in police academy training. Harvey objected for lack of foundation, but the trial court overruled the objection, reasoning that if the officer learned it at the police academy, “he can testify to it.” Harvey was convicted and moved for a new trial, arguing the officer gave improper expert testimony as a lay witness.

Key Legal Issues

The central issue was whether the officer was qualified to testify as an expert on alcohol burn-off rates under Utah Rule of Evidence 702(a), which requires that a witness be “qualified as an expert by knowledge, skill, experience, training, or education” to testify about “scientific, technical, or other specialized knowledge.”

Court’s Analysis and Holding

The Court of Appeals reversed, finding the officer’s testimony was improperly admitted. The court distinguished between subjects officers can observe and form opinions about based on training and experience (like signs of impairment) versus scientific testimony that “requires a formulaic calculation derived from scientific understandings of physiological processes.” The court emphasized that burn-off rate testimony is “necessarily scientific testimony derived from lab testing, based on technical training, and presented by an expert qualified in that area.” Merely learning about burn-off rates in a general police academy course was insufficient foundation for expert testimony on this technical subject.

Practice Implications

This decision reinforces that courts must carefully scrutinize the foundation for expert testimony, particularly on scientific subjects. Practitioners should examine not just whether a witness was exposed to information, but whether they have sufficient depth of knowledge to qualify as an expert. The ruling also demonstrates the importance of challenging technical testimony that lacks proper scientific foundation, as such errors may not be harmless if other evidence of impairment is weak.