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- June 1990
-
- FOCUS ON FORENSICS:
- LATENT SHOEPRINT ANALYSIS
-
-
- For decades, fingerprints have provided investigators
- invaluable clues to establish the identity of criminals. Yet,
- another type of print impression that could be just as valuable
- has been widely overlooked. Latent shoe prints exist in almost
- all interior crime scenes but are often ignored by investigators
- or destroyed by initial responders before the prints could be
- processed.
-
- Latent shoe prints are impressions of shoe treads left by an
- individual on a surface. While these prints cannot be seen by
- the naked eye, they can be revealed using standard fingerprint
- powders. Although investigators routinely search for visible
- shoe prints on interior surfaces and shoe impressions in
- exterior crime scenes, they often overlook the existence of
- latent shoe prints.
-
- Like fingerprints, latent shoe prints can be used to place a
- suspect at a crime scene. Though each shoe manufacturer produces
- hundreds of various styles of footwear with the same tread
- design, these identical prints quickly become unique through the
- owner's use. Wear will vary depending on individual walking
- styles and contact with different surfaces. Any scratch, nick or
- cut will result in points of comparison, making the shoe ``one of
- a kind.''
-
- Most casual shoes have rubberized soles that, when exposed
- to light amounts of moisture, react in a way similar to a finger
- leaving its mark on a surface. Vinyl linoleum, smooth tile, and
- painted floors provide the best surfaces for recovery of latent
- shoe prints.
-
- Many of the same factors that are involved in lifting
- fingerprints are to be considered in recovering latent shoe
- prints. The surface must be smooth enough to reveal the
- characteristics of the soles. Temperature and weather conditions
- must be conducive to preservation of the impressions. And, like
- fingerprints, latent shoe prints are fragile and can be damaged
- if further contact is made after the print is placed. They can
- be easily altered or destroyed by first responders and curious
- bystanders; therefore, it is important to carefully secure the
- crime scene if recovery of the prints is to be successful.
-
- Latent shoe prints have not been widely used in crime scene
- investigations. Although recovery of the prints depends on
- several unpredictable variables, they may yield valuable
- information and, therefore, should be considered a viable option
- for investigators.
- ____________
-
- Information for this column was provided by Dwain A.
- Pierce, Criminalistics Specialist, Police Department, Knoxville,
- Tennessee.