Quantifying Randomly Acquired Characteristics on Outsoles in Terms of Shape and Position

• NCJ Number: 255196
• Date Published: September 2016
• Length: 13 pages
• Author(s): Jacqueline A. Speir; Nicole Richelelli; Michael Fagert; Michael Hite; William J. Bodziak
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical), Report (Study/Research), Report (Grant Sponsored), Program/Project Description
• Grant Number(s): 2013-DN-BX-K043
• Award: A Quantitative Assessment of Shoeprint Accidental Patterns with Implications Regarding Similarity, Frequency and Chance Association of Features

Annotation

The aim of this study was to clarify the discrimination potential of footwear as a source of forensic evidence by further characterizing the chance association in position, shape, and geometry of randomly acquired characteristics (RACs) of a semi-random selection of footwear.

Abstract

Footwear evidence has tremendous forensic value; it can focus a criminal investigation, link suspects to scenes, help reconstruct a series of events, or otherwise provide information vital to the successful resolution of a case. When considering the specific utility of a linkage, the strength of the connection between source footwear and an impression left at the scene of a crime varies with the known rarity of the shoeprint itself, which is a function of the class characteristics, as well as the complexity, clarity, and quality of randomly acquired characteristics (RACs) available for analysis. In addressing this issue, the current study developed a partially automated image processing chain, including steps for automated feature characterization. This article details the methods, procedures, and type of results available for subsequent statistical analysis after processing a collection of just over 1,000 shoes and 57,426 randomly acquired characteristics. (publisher abstract modified)