Analytical technique could lead to better crime scene investigation
As forensic evidence goes, gunshot residue can be full of holes. But a new technique could provide a more definitive link between suspect and gun. A tool that employs lasers may allow investigators to match residue alone to a specific caliber of firearm, scientists report in two recent papers in Analytical Chemistry.
“Anything that’s going to enhance or expedite the detection of gunshot residue and provide stronger evidentiary value is a way forward,” says analytical chemist Jason Birkett of Liverpool John Moores University in England. “This work is very good and very novel and will do nothing but assist.”
Along with the bullet, a cartridge or round also contains a propellant (usually gunpowder) and a primer. When the firing pin strikes the primer cap, the primer ignites, igniting the propellant and expelling the bullet from the gun. “It’s a very complicated chemical reaction involving extremely high tempera