FOOTPRINTS
By: Audrey O'Donnell
For many years fingerprints have been a main identifier, but recently footprints have been discovered to be an equally helpful identifier. Since criminals must enter and exit the crime scene somewhere, there is a good chance they will leave a shoe/foot print. Even though criminals make an effort to cover their face and fingerprints, they rarely remember to cover their tracks.
A foot has a set of ridges that are a print unmatched to any other person. Also with feet, shoe prints are now identifiable. The indentations a shoe leaves in the ground can be studied, recorded, and matched to other prints found in other locations.
To preserve the prints detectives first take detailed photographs that can be scanned onto a computer for analysis. Also, technicians can make a mold of the print so a duplicate is available. The basic methods of recording footwear impressions are; photography, documentation/sketching, casting, and lifting.
The size of a shoe can help detectives estimate the height/weight of a person. The forensic scientist can compare how deep the print is and how solid the oil was/whether it was damp or not at the time, investigators will have an idea on the weight of the person
Visible prints: a visible print is when the footwear steps into a substance and is contaminated by it. The shoe then comes in contact with a clean surface and the print is pressed onto that surface. This print is now visible to the naked eye. The most common footprints are left with blood, grease, oil, or water. These prints should be photographed first. Plastic prints are impressions that happen when the footwear steps into a soft surface and creates an impression. This is common in mud, snow, wet sand, or dirt. Latent prints are prints found on a generally smooth area. These prints can be recorded with powders, chemicals and forensic lights so the print can be visible and collected. These prints should once again be photographed first.
Packaging Footprints
Detectives usually take extremely detailed photographs of the print. In other cases technicians will make a casting of the print can be duplicated. The casting process involves pouring a dense liquid into the shoe imprint and after it set, the cast can be picked up in one piece. This allows for an exact replica of the shoe print.
Footprints
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