Crime Scene Investigator Network

Crime Scene Investigator Network Newsletter

MARCH 2019
This month's newsletter is brought to you by the 2019 CSI Summer Academy

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

Criminals track dust particles to and from virtually every crime scene, but particles on a suspect's shoes are seldom used as evidence linking the accused to the crime. In this NIJ-supported project, researchers assert that investigators can use small particles from shoes to determine where a person — suspect or victim — was last walking.

After many years of examining populations of very small particles on everything from illegal shipments of elephant tusks to carpet fibers in the trunk of a murder suspect’s car, forensic investigators David and Paul Stoney have turned their attention to particles found on shoes. Specifically, they wanted to know if the three different categories of particles found on a shoe — loosely, moderately, and tightly held — could provide a narrative of where that shoe had been.

Researcher stepping on paper to knock off and collect loosely held from shoe Removal of the most loosely held particles by walking on paper.

To determine how much such particles could reveal, the two researchers walked through three test environments wearing a total of 36 pairs of shoes — half of them tennis shoes and half work boots. Walks of 250 meters were done at three sites chosen because of their different soil minerals — the Appalachian Trail, the Luck Stone Quarry, and Piney River, all in Virginia. The sites were all dry and dusty and, following each exposure, the footwear was repackaged in its original box between folds of butcher paper.

The project, supported by an NIJ grant, was designed to test the hypothesis that by separately analyzing percentages of loosely held, moderately held, and strongly held particles from a shoe, investigators could detect the sequential exposure of the shoe to different environments. If the hypothesis proved true, an investigator might be able to determine a sequence of where a shoe had been. However, after examining the particles recovered from the test walks, the researchers rejected their hypothesis.

"Under the experimental conditions, the contact surface of footwear was found to be overwhelmingly dominated by the most recent exposure," the two researchers noted in their summary report. Prior research indicated that some particles that had transferred to different types of trace evidence would be rapidly lost, while some would be retained longer, allowing for a sequential profile of the particles. That is not the case for shoes, they concluded. Walking through the test environments, they wrote, "results in the virtually complete removal and replacement of particles adhering to the contact surfaces from prior, similar exposures."

The clear implication of the research, they said, is that "although particles on the contact surfaces of footwear [loosely held particles] are removed and replaced, those that are present on the more recessed areas of the sole [moderately and tightly held particles] are not." That fact does not exclude particle evidence as potentially valuable evidence, they indicated.

"For example," the researchers said, "in cases where a body is found and may have been transported after death from one location to another, the contact surfaces of the footwear will retain unmixed small particle traces that are directly representative of the last location where the deceased walked." By examining those particles, investigators can determine if the body was moved and use the particles as clues to locate from where the victim was moved.

On footwear from a suspect, the researcher said, the loose particles will likely not match those from a crime scene and attention should be focused on the more tightly held particles in recessed surfaces. "Recessed areas of footwear are responsible for the mixtures of particles arising from activity before, during and after the crime itself," the researchers said. Examining particles in the recessed areas could allow researchers to develop a more sophisticated profile of where a shoe has been, although more work is needed to determine if that is scientifically relevant.

About This Article

The research described in this article was funded by NIJ cooperative agreement number 2014-DN-BX-K011, awarded to Stoney Forensic, Chantilly, VA. This article is based on the grantee report "Differential Sampling of Footwear to Separate Relevant Evidentiary Particles from Background Noise" (pdf, 35 pages) by David Stoney, chief scientist, Stoney Forensic.

< read the report "Differential Sampling of Footwear to Separate Relevant Evidentiary Particles from Background Noise" >

National Institute of Justice, "Determining Where A Shoe Last Walked by Measuring 'Loosely Held Particles'," November 27, 2017,
This Month's Featured Resource on the Crime Scene Investigator Network Website

Handbook of Forensic Services
Federal Bureau of Investigation

The Handbook of Forensic Services provides guidance and procedures for safe and efficient methods of collecting, preserving, packaging, and shipping evidence and describes the forensic examinations performed by the FBI's Laboratory Division and Operational Technology Division.

The successful investigation and prosecution of crimes require, in most cases, the collection, preservation, and forensic analysis of evidence. Forensic analysis of evidence is often crucial to determinations of guilt or innocence.

<View the Publication>

New CSI and Forensic Job Announcements

The most comprehensive listing of Crime Scene Investigation and Forensic
employment opportunities on the internet! We typically have over 100 current listings!

To be notified of job openings as they are posted, follow us on Twitter: Job Posting Alerts
or sign up for daily email alerts: Daily Job Posting Alert Emails

Crime Scene Investigator
North Miami Police Department, North Miami, Florida, USA

Final Filing Date: May 7, 2019
Performs advanced technical work in the detection, evaluation and preservation of crime scene evidence. Responsible for maintaining the chain of custody for the presentation of collected evidence in court.
<View complete job listing>
Evidence Officer
Monterey Park Police Department, Monterey Park, California, USA

Final Filing Date: Open until filled
Performs a wide variety of duties relating to custody, record keeping, control of property and evidence, including video evidence processing and duplication; court liaison duties, assisting investigations personnel with crime scene processing such as latent print collection, crime scene photography, and DNA collection, and other non-hazardous related duties as required.
<View complete job listing>
Firearms ID Examiner III
Institute of Forensic Sciences, Houston, Texas, USA

Final Filing Date: April 21, 2019
Evaluations and test firing of various types of firearms. Performs moderately complex and complex analysis of submitted firearms and firearms related evidence that may include hazardous biological and chemical substances. Performs serial number restorations (firearms). Performs gunshot residue / distance determination examinations. Issues reports accurately reflecting the results of examinations. Provides expert testimony in the discipline of Firearms Identification.
<View complete job listing>

Digital Forensic Analyst
Grand Junction Police Department, Grand Junction, Colorado, USA

Final Filing Date: April 12, 2019
Perform forensic computer/digital evidence recovery and analysis on a wide variety of specialized visual and/or computer based related peripheral equipment and data storage devices. Perform a variety of advanced procedures to analyze digital multimedia evidence. Perform advanced analytical procedures to determine authenticity and integrity of evidence and comparative evaluations.
<View complete job listing>
Forensic Scientist I - Latent Prints
Colorado Department of Public Safety, Bureau of Investigation, Grand Junction, Colorado, USA

Final Filing Date: April 19, 2019
Responsible for the preservation, screening/analysis and interpretation of latent print evidence collected in criminal cases for federal, state and local law enforcement agencies.
<View complete job listing>
Evidence Specialist
King County Sheriff's Office, Seattle, Washington, USA

Final Filing Date: March 31, 2019
Responsible for handling Public Safety evidence and property transactions and dispositions. Job duties include the proper disposal and storage of evidence and personal property while adhering to all legal requirements.
<View complete job listing>

Search for more job listings in Crime Scene Investigations and Forensics
<Crime Scene Investigator Network Employment Listings>

To be notified of job openings as they are posted, follow us on Twitter: Job Posting Alerts
or sign up for daily email alerts: Daily Job Posting Alert Emails

Other Resources on the Crime Scene Investigator Network Website
Not Subscribed to this Newsletter?

If you are not subscribed to this newsletter, you may subscribe with this link: SUBSCRIBE via email
or on our website by clicking here: SUBSCRIBE on our website.

To Unsubscribe

To unsubscribe from future e-mail newsletters, please click here: UNSUBSCRIBE
or email with your request to unsubscribe.

Copyright ©2019 Crime Scene Resources, Inc.

Crime Scene Investigator Network
PO Box 1043
Wildomar, CA 92595-1043