Researchers in the University Department of Chemistry and the Police's scientific support unit have developed the method that enables scientists to 'visualise fingerprints' even after the print itself has been removed. They conducted a study into the way fingerprints can corrode metal surfaces. The technique can enhance – after firing– a fingerprint that has been deposited on a small calibre metal cartridge case before it is fired.
Dr John Bond, Honorary Fellow at the University of Leicester and Scientific Support Manager at Northamptonshire Police said: "For the first time we can get prints from people who handled a cartridge before it was fired."
"Wiping it down, washing it in hot soapy water makes no difference - and the heat of the shot helps the process we use.
"The procedure works by applying an electric charge to a metal - say a gun or bullet - which has been coated in a fine conducting powder, similar to that used in photocopiers.
"Even if the fingerprint has been washed off, it leaves a slight corrosion on the metal and this attracts the powder when the charge is applied, so showing up a residual fingerprint.
"The technique works on everything from bullet casings to machine guns. Even if heat vaporises normal clues, police will be able to prove who handled a particular gun." (Full Story at eurekalert)
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