Professor Linacre’s trademark rigour was developed during 17 years of crime scene investigations in Glasgow, and has not waned since commencing his research career with Flinders in 2010. “We can’t afford for any of this to be wrong or have errors. These can’t just be bright ideas. The research results have to be peer reviewed and irrefutable. It has to stand up in a court of law,” he says, noting that the Flinders team has been teaching the system to crime scene investigators from the NSW and WA police forces, and attracted recent international attention from Finland Police.
Professor Linacre’s team is now researching the so-called shedder status of different people, measuring the propensity of a person to shed skin cells and deposit their DNA. Three grades of shedders have been identified, from heavy shedders depositing many cells with every touch, to very light shedding. Rigorous testing has also shown that a person’s shedding status is consistent across all parts of their bodies (from both left and right hands, for example) and does not change over time.
“To identify someone’s shedder status is another means of more accurately identifying a DNA profile that will be able to stand as irrefutable evidence in court.”
Professor Linacre is also confident of unlocking information about secondary DNA transfer to trace the history of DNA on an object and identify specific timelines of when each deposit was made, leading to positive identification of people in exact locations at specific times.
“It’s a very significant piece of the larger forensic puzzle,” he says. “Our work brings closure. It’s a relatively immediate science. Each piece of research leads us through another door – and onward.”