Shoeprints

Shoeprints are often times recovered at crime scenes.  These impressions can be compared to the suspect’s shoes to see if those shoes could have made that impression.  Impressions at scenes can be collected in several different ways.  They can be photographed, cast, lifted, and/or the whole item with the impression might be collected.  Please see Evidence Submission for more information.

                                                    
                                                          
                                                      Suspect’s Shoe                                Sulfur cast of the Impression in Snow Left at the Scene 

 

Tire Tracks

Tire tracks can be found in snow, mud, dirt, or sand, or even on a victim at a crime scene. 

These tracks can be collected by photographing, casting, lifting, and/or collecting the clothing from the victim.  In the trace evidence section, the tire tracks from the scene can then be compared to tires or known tire impressions from the suspect’s vehicle. 

 Make and Model Determination

When unknown shoeprints and/or tire tracks are found at a crime scene, the make and model of the shoes and/or tire that made those impressions may be identified using various databases.  This information could help generate investigative leads. 

Unknown shoeprint impressions are first searched through the internal BCA Footwear Reference Collection database.  This database is made up of over 600 shoeprint impressions that have been obtained over multiple years of casework.  Similarly, unknown tire track impressions are searched using Tire Tread Design Guides®.  These guides are published annually and provide an accurate, current collection of technical tire information.

If unknown shoeprint or tire track impressions are not found using these initial resources, a second database search is completed using a software program called SICAR® (Shoeprint Image Capture and Retrieval Database).  SICAR is a database made up of thousands of shoeprint and tire tread patterns that have been submitted by manufacturing companies, forensic laboratories, and law enforcement agencies.  Specific shapes or pattern elements in the unknown impression are coded to certain areas of a shoe or tire tread in the program.  This coding process generates a list of known shoes and/or tires with similar characteristics which can then be examined to determine a potential source of the impression.

Please see Evidence Submission for more information.