A comparison study between vinyl static cling film and gelatin lifters in the collection of footwear impressions left in dust
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Abstract
Footwear impressions are encountered frequently during crime scene investigations. They are considered quite fragile, and collection of this type of evidence after proper documentation is highly recommended1. A common method of collection for dust impressions is the Electrostatic Dust Lifting technique (ESDL), which requires an electric charge and carries a risk of shock to the user2. A footwear impression collection product that also utilizes static electricity, but without the need for any additional power source was validated in 2011: Arrowhead Forensics’ “Stat-Lift™” (Arrowhead Forensics, Lenexa, KS), also referred to as Vinyl Static Cling Films (VSCF). This previous validation study compared the quality of the VSCF collection results to those produced by the ESDL, and found that the VSCF outperformed the ESDL in the level of contrast and detail of the impression on the lift3.
Gelatin Lifters are a well-established method for collecting dust impressions at crime scenes, using a “low-adhesive gelatin” to recover the evidence4. This study compares the VSCF (specifically the Stat-Lift™) to the established Gelatin Lifters in several categories, such as contrast, detail, and completeness of impression collected on the lift.
Three common flooring materials were collected for substrates, which included vinyl tile, hardwood, and marble tile. Dust was collected via vacuuming and emptied into a container. A volunteer then stepped into the container and created dust impressions on the substrates, reapplying dust between impressions. The impressions were created in triplicate: three Stat-Lifts™ and three Gelatin Lifters for each substrate. The impressions were subsequently photographed. These photographs were randomized and anonymized before being sent to three competent forensic footwear examiners. Every photograph was evaluated by each of the examiners using a series of questions with a ranking system as a guide.
After the results were returned from the volunteers, they were organized by category and examined. Gelatin Lifters ranked higher than the Stat-Lift™ in each category, ranging from the visibility of the impression, lack of distortion, observance of delicate or fine details in the impression, and their suitability for comparison purposes.
Description
2025