by Carrie Soderberg
Every day we leave behind traces of who we are. Every surface we touch, every item we hold. There is not one fingerprint in the world that is alike, unless you count one chance in 64 billion that your fingerprint will match another. Not even identical twins share the same fingerprints. And a fingerprint’s uniqueness is what makes it so appealing to law enforcement.
Marks on a glass, door handles, office desks, even bank notes can be detected, making it easier for forensic scientists to find the owner of the fingerprints. But there is one surface impossible to take a fingerprint from. Human skin.
Imagine a detective investigating a gruesome homicide. He is chasing a killer who strangles his victims. No traces are found, not even DNA. But what if we were able to catch him by lifting his fingerprints off the skin of the victim?
Often referred to as the holy grail of fingerprint technology, finding and taking a finger mark from someone’s skin is something most scientists in the field of chemical forensics dream of.
But last year, Dr Xanthe Spindler, a Chancellor’s Post Doctoral Research Fellow at the University of Technology Sydney (UTS) Centre for Forensic Science made a breakthrough. She developed an immunogenic method with the potential to recover usable fingerprints from skin and old evidence. It was a first that received worldwide acclaim. Ever since her paper into antibodies was published, interest in her research has grown, both in academia and publicly.
She is hoping that her work using antibodies designed to target amino acids present in sweat, which are deposited in most fingerprints, can eventually be used by forensic police in the field.
“With a bit of tweaking hopefully we can get it to work on any evidence,” she says.
Dressed in a tulle skirt, white top and boots, Xanthe Spindler could pass for any young graduate at UTS, where she works in the laboratory at The Centre for Forensic Science. But even without the laboratory coat, it is clear that fingerprints are her passion.
Fingerprints have been used by forensic investigators for more than 100 years and it is still one of the most widely used methods in the business of crime fighting. For many years though, there were almost no new techniques in fingerprint technology. Powdering remained the main method. Then something happened.
“In the last 20 years the research into fingerprints has just skyrocketed,” Dr Spindler says.
She is now part of that foray into the future, and a member of an elite group of scientists internationally who specialise in fingerprint technology.
Dr Paul Kirkbride, Chief Scientist, Forensic and Data Centres at the Australian Federal Police, hopes that Dr Spindler’s research may be used one day in the field.
“It is a very difficult technique to achieve but this may well be one way of addressing the finger marks on skin issue,“ he says
The hope is that, apart from being able to detect fingerprints on skin, the application can be used on many other surfaces that are currently too difficult. But cracking the human skin it is still no easy task.
“You have got the problem that the background is almost identical to what you are trying to target,“ she says.
Dr Paul Kirkbride, agrees. “We’re trying to find a human deposit on human skin so it is a very high degree of difficulty.”
The Australian Federal Police and UTS are now combining forces in an attempt to find more funding to support an in depth investigation into Dr Spindler’s work.
In the meantime her work continues.
“Hopefully if the proposal we’ve put forward is successful then the research could commence next year here at the laboratories at the AFP,” Dr Kirkbride says.
Over the years, the AFP has collaborated with a number of universities in the area of fingermark research. Most notably, the first collaboration between AFP and UTS resulted in a protocol for developing fingerprints on polymer bank notes, through research by former PhD student Naomi Speers. It is a standard technique used in the field today.
“No matter what level of sophistication, every police agency around the world will conduct fingerprint detection. It is a core part of operations,“ Dr Kirkbride says.
“My role as chief scientist is to identify scientists in academia that have something to offer and then in partnership develop a research proposal.”
He says that can involve something as simple as engaging an honours student or PhD student or in the case of Dr Spindler, attempting to put forward a proposal that seeks funding from the government for research.
“We have a number of ways of engaging with universities depending on the type of outcome that we desire.”
But in a world where DNA is all the rage, is there still a place for fingerprint detection?
Professor Claude Roux, Director of the Centre for Forensic Science at UTS, is another passionate advocate for fingerprint technology.
“The view that fingerprints are so twentieth century, and now there is DNA instead, is a very short-sighted view,“ he says. “There are many cases where fingerprints give better results. Overall it is a holistic approach to traces that we deal with in forensic science, not just one method.”
Australian research into fingerprint identification started at the Australian National University in the early eighties. Professor Chris Lennard was one of the research fellows at the time. He later joined the AFP before becoming head of the forensic studies discipline at the University of Canberra, which is a collaborative partner with the UTS Centre for Forensic Science.
Coming from an AFP background, Professor Lennard is adamant that applied research in areas like forensic science should never be done in isolation, away from the industry.
“We desperately need support from industry partners such as the AFP to make sure the research we do is relevant. And there has to be a reason for doing it.”
He says the value in forensic science should never be undersold. “Not only does it provide evidence and link someone to a crime, often forensic evidence excludes people from scene.”
Xanthe Spindler’s method of detecting fingerprints on skin and old surfaces could be a reality in years. Cold cases could be opened, even Jack the Ripper would be out in the open.
Dr Spindler has managed to develop fingerprints that were up to 12 months old. “Provided you are not seeing any sort of mechanical damage or the samples have been left out in the open, there is really no upper limit to what we could do.”