This presentation of the National Institute of Standards and Technology’s (NIST’s) Footwear Impression Comparison System guides the forensic analyst through the workflow of footwear impression comparison from crime-scene footwear impressions through comparison of an impression with a particular shoe sole, using current forensic capabilities and then noting what advancements are needed for improvement in footwear impression comparison.
Figures first show the manual annotation of the test impression footprint with the questioned impression, accompanied by a figure that shows the automated alignment and comparison of the design, size. and wear of the two impressions. The system then proceeds to “revamp with casework focus” with photos of shoe impressions from a crime scene alongside a lineup of test impressions of a “lineup” of sole impressions from suspicious shoes of supposed “persons of interest” or suspects. Markups are then shown of a test impression from a suspect shoe alongside a markup of the crime-scene shoe-print. An alignment procedure is then outlined, and a size metric of the markup is portrayed. This is followed by procedures and illustrations of capturing design and wear metrics and RAC metrics. Relevance metrics are then displayed in figures and photos. Data visualization contains figures and captions for the clarity of the crime-scene impression and its similarity to the test shoe, with steps outlined. Suggestions for future research and development for footwear comparisons are to 1) develop automated tools to assist with markup; 2) use images from black box studies to evaluate and improve FICS; and 3) use NIST FICS outputs and black box response to predict distribution of conclusions across examiners.