Colorado’s second-highest court upheld a defendant’s conviction for aggravated motor vehicle theft last week, even though it was unclear how the Thorton Police Department estimated the value of the stolen car.

Officer Marc Faivre encountered Ashley Shelee Gibbens-Martinez in a stolen Kia Sorento in a parking lot. There was visible damage to the door and the ignition, but Gibbens-Martinez maintained that an acquaintance had just let her borrow the car.

At trial, the prosecution did not argue that Gibbens-Martinez stole the Kia, but only that she knew she was operating a stolen car.

The severity of the crime was tethered at the time to the value of the vehicle, with $20,000 being the dividing line between a class 5 and a class 6 felony.

Adams County jurors heard from the vehicle’s owner that the original purchase price was $56,000 several years earlier. Faivre testified about a Kelley Blue Book estimate placing the Kia’s value somewhere between $22,000 and $25,000, based on the year, make, and model.

The prosecution acknowledged that Faivre did not generate the estimate, and it was unclear who did. The defense argued that Kelley Blue Book estimates require many variables beyond the basic ones captured in the report.

Then-District Court Judge Robert W. Kiesnowski Jr. allowed the prosecution to use the estimate. Jurors convicted Gibbens-Martinez for theft of a car whose value exceeded $20,000.

On appeal, the defense argued that the Kelley Blue Book report was inadmissible as evidence because no one could speak to its creation.

“Officer Faivre did not create the valuation, nor did he testify as to the name or role of the individual who did. He did not testify that he personally observed anyone create the valuation. Indeed, he did not even testify that he had seen the valuation prior to taking the stand,” wrote public defender Andrew Vierra. Faivre was allowed to “simply read off a sheet of paper he may have never seen before.”

By 2-1, a three-judge Court of Appeals panel disagreed.

Faivre’s testimony about the basic characteristics of the car “was sufficient, albeit minimally, to authenticate the report,” wrote Judge Craig R. Welling for himself and Judge Steve Bernard in a Sept. 3 opinion.

Welling added that the defense could have cast doubt on the accuracy of the estimate at trial.

“For example, if Gibbens-Martinez was concerned that the condition of the car was worse than what was used to generate the report — which would have meant that the value of the stolen car was lower than what was reflected in the report — she could have asked what condition of the car the report was based on or if the report accounted for the condition Officer Faivre found the car in, including the damage to the driver’s side door and ignition,” Welling wrote. “She didn’t cross-examine Officer Faivre about this or any of the concerns she raises about the reliability of the report to establish the value of the stolen car.”

The panel’s majority also determined the estimate did not violate Gibbens-Martinez’s constitutional right to confront the witnesses against her.

Judge Katharine E. Lum disagreed, believing Faivre’s testimony was insufficient to establish the report was an authentic piece of evidence.

“While I acknowledge that the bar for authentication is low, it is not, in my view, this low,” she wrote. “If the majority’s opinion is the rule, then all that is required to authenticate a document is for a witness who has apparently never seen it before to testify about what it ‘appears to be’ based on nothing more than reading the document itself. That effectively makes any document self-authenticating, which is particularly troubling in an age when AI-generated evidence has created unprecedented authentication challenges for courts.”

Lum added that the Kelley Blue Book report likely affected the verdict because it enabled jurors to determine more precisely whether the $20,000 threshold for the more serious felony was crossed. She would have ordered a resentencing for Gibbens-Martinez on the less severe felony or allowed prosecutors to try Gibbens-Martinez again.

The case is People v. Gibbens-Martinez.