A simple driving-while-intoxicated case turns into an examination of evidence rules and use of expert witnesses.
Ute Guerre-Chaley was arrested after submitting to a preliminary breath test (PBT) that was administered with a portable device by a police officer in the field. Guerre-Chaley registered a .079 % blood alcohol content which is just under the state’s legal limit of .080 %. Later, during two other tests, she registered .090 % and above.
The defense argued that Guerre-Chaley was not drunk when she was initially pulled over and was intoxicated only later at the police station when the other tests were administered. An expert witness was introduced that would provide an opinion on the PBT, but the state argued that it was inadmissible. The Alaska Court of Appeals ruled that the trial judge correctly determined that the witness could not discuss the PBT without some evidence of scientific validity or reliability. Related Link: Ute Guerre-Chaley v. State of Alaska