University researchers have announced that “bullet fingerprinting” technology has taken another step forward.
The technique of “visualising fingerprints” from metal surfaces, such as fragments of bullet casing, has already proved a huge success in the world of forensic investigation.
Developed by Dr John Bond, from Northamptonshire Police Scientific Support Unit, in collaboration with scientists from the University of Leicester – it allows scientists to find prints even after they have been removed.
The discovery was named last year as one of Time Magazine’s top 50 inventions of the year and Dr Bond’s assistance has already been sought by police forces across the world to crack “cold cases”.
Today researchers at the university’s chemistry department announced developments of the technology, uncovering new ways of recovering prints from metal surfaces.
Researcher Alex Goddard has uncovered a natural technique that he believes is so simple it has been overlooked until now.
It involves studying chemical and physical interactions between the metal and fingerprint sweat deposit.
Using advanced surface imaging techniques, such as an Atomic Force Microscope, nanoscale observations of fingerprinted brass samples can identify the optimum conditions to promote the natural enhancement of the fingerprint and improve the recovery rate.
It has also proven that components of the sweat deposit survive washing and wiping of the surface.
Mr Goddard said: “Once a finger has touched the metal surface, a residue remains behind, this starts to react with the metal and an image of the fingerprint can be developed by use of elevated temperature and humidity, with the resultant image becoming a permanent feature on the surface of the metal.
“Currently, fingerprint recovery from bullets is very low; less than one per cent, This uses a natural process and even if it only leads to small increase in success rate, then that would be significant.
“Previous recovery methods include applying powder to the material which can actually damage the evidence.
“This new technique promotes a naturally occurring process which does not involve adding anything to, or damaging, the evidence.
“Instead, it employs heat and humidity to promote the enhancement of the fingerprint image, there are also indications that it could be used after other techniques have failed, perhaps as a last resort.”
Mr Goddard recently presented his findings at the University of Leicester’s Postgraduate Research Festival.
Dr Bond, also an Honorary Research Fellow at the university’s Forensic Research Centre, added: “I am delighted that this research in the chemistry department is producing really interesting and useful results.
“This is an important area of forensic research and Northamptonshire Police is proud to be associated with the University.
“I look forward to further developments.”