ShoeCase: A data set of mock crime scene footwear impressions

This project's main objective is to create an open-source database containing a sizeable number of high-quality images of shoe impressions. The team at the Center for Statistics and Applications in Forensic Evidence (CSAFE) worked to collect images that could be representative of those found at crime scenes and made publicly available to the broader forensic and research communities. With mixed impression types (full blood impression, partial blood impression, and dust), flooring (vinyl and tile), lift techniques (gel lifts), and digital file types (TIF, XMP, CR3, and JPG). Our data was collected with the intention of reproducibility, using simple but specific protocols and easily accessible materials. The complete dataset includes 936 unique shoeprint images contained in 3,275 digital files. Data collection consisted of trained volunteers making shoe impressions on flooring with the 2 mediums: Spatter blood and graphite powder. They would wear the shoe, step in the material, and then walk on the flooring. For the blood prints a separate “lighter” step was made for a partial print. The blood prints were brought to the photography station where researchers labelled it and took a photograph. Graphite prints were covered with a gel lifter before being brought to the photography room. There the researchers removed the lift, then labeled and photographed it. We hope that our data will be of significant use for researchers, examiners, and anyone that could benefit from the use of a large dataset like this. Footwear datasets are often difficult to find, especially ones that resemble crime scenes, so our data can help fill that gap.