Catching criminals comes a step closer

19 Dec 2012

A revolutionary technique to capture shoeprints invisible to the naked eye at crime scenes has been developed by a researcher funded by the Engineering and Physical Sciences Research Council (EPSRC).

The breakthrough in forensic science gained widespread media coverage.

Dr Kevin Farrugia from the University of Abertay adapted existing print visualisation techniques so that shoeprints left on fabrics or floor coverings can be revealed clearly and in detail. The technique works on both fresh and older prints, and so could be used to solve cold cases of crime.

Dr Farrugia explains, "Footwear marks can be made in many contaminants, for instance blood, mud, urine and dust. They can be left on all sorts of different fabrics, like cotton or denim, as well as on patterned and dark material, which makes them more difficult to see.

"When someone steps in wet blood though, the first few prints they leave will be a wet smudge, so no fine detail from the footwear sole can be recovered.

"However, as the marks fade and becomes less visible, the pattern on the sole of the shoe, by contrast, becomes much clearer and better defined. And it's these prints - the ones that we can't actually see - that are the most useful at a crime scene, especially when it isn't possible to recover other types of evidence such as fingerprints and DNA, because they can tell you things like what size, and even what brand, of shoe the perpetrator was wearing when they committed the crime.