Tom Darnell

Tom Darnell testified for the State about his laboratory examination of firearms, ammunition, and a phone.

Darnell explained the methods used to develop and compare latent prints, including Superglue fuming, fluorescent staining, alternate light sources, and photography. He observed no fingerprint evidence on six .300 Blackout casings, two shotshells, the Benelli shotgun, or the individual cartridges from a loaded magazine. Other firearms and the magazine produced results of no value for comparison, while the phone showed finger contact but lacked enough clear detail for comparison. He identified the phone only through laboratory records as an evidence item and did not independently confirm its owner.

Darnell also collected touch-DNA swabs from selected firearm surfaces, two shotshell head stamps, and the phone. His examination did not supply the later DNA-analysis results.

Cross-examination established that Darnell processed only evidence delivered to the laboratory, did not attend the homicide scene, and had not reviewed the scene team's notes. He could not say what investigators processed at the scene. He explained that contact does not necessarily produce a recoverable print and that heat, friction, weather, later handling, and insufficient perspiration can affect recovery. He also distinguished an item with no observed fingerprint evidence from one bearing print evidence that lacked value for comparison.

On redirect, Darnell explained that crime-scene personnel and latent-print examiners worked in separate departments and that scene personnel were trained to process items that could not be transported. He testified that no bloody prints were submitted to him, but did not offer a conclusion about whether any were found or processed at the scene.