U.S. flag

An official website of the United States government, Department of Justice.

Determining Where A Shoe Last Walked by Measuring "Loosely Held Particles"

NCJ Number
251404
Date Published
November 2017
Length
2 pages
Annotation
This is a summary of the report on a NIJ-funded project in which researchers determined that crime investigators can analyze small particles adhering to a victim's or suspect's shoes to determine where he/she last walked.
Abstract
The two researchers, David and Paul Stoney, had spent many years examining populations of small particles on items that ranged from illegal shipments of elephant tusks to carpet fibers in the trunk of a murder suspect's car. In the current project, they used their expertise to determine whether three different categories of particles on a shoe could provide a narrative of where that shoe had been. The three categories of particles examined were classified as loosely, moderately, and tightly held. The hypothesis tested was that by separately analyzing percentages of these three categories of particles on a shoe, investigators can detect the sequential exposure of the shoe to different environments where the shoe wearer had walked. After examining the particles recovered from the test walks, the researchers rejected the hypothesis, concluding that "under the experimental conditions, the contact surface of footwear was found to be overwhelmingly dominated by the most recent exposure." They also concluded, however, that shoe-particle evidence is potentially valuable. They cited a case in which a body is found and may have been transported after death from one location to another. In such cases, the contact surfaces of the shoes will retain unmixed small particle traces that are directly representative of the last location where the deceased walked. An examination of those particles can determine whether the body was moved, and the particles can be used as clues to locate the spot from where the victim was moved.