Identifying sexual offenders may now get easier with the help of a new method that can detect fingerprints containing condom lubricants left behind.
British researchers have developed a technique that could be used to prove suspects had contact with a condom, thus placing them at the scene of the crime, reports the Sydney Morning Herald.
It may also be able to identify the unique ridge pattern of offenders' fingerprints.
Assailants were becoming increasingly aware of forensic issues, such as their DNA being transferred, and it was common for condoms to be used and removed from the scene, wrote the Sheffield Hallam University researchers.
"In addition, one of the first instincts of a sexual assault victim is to try and expel the sense of violation by washing themselves and their clothes," they wrote.
However, sexual offenders were less likely to consider the possibility of lubricant transferring onto their fingertips and then into fingermarks left at the scene, said the authors.
The team successfully detected lubricant from two common condom brands left behind by fingermarks, even several weeks after it had been deposited.
The researchers used MALDI-MSI (matrix-assisted laser desorption/
ionisation mass spectrometry imaging), a technology that can map fingermark ridge patterns.
One of the study's authors, Simona Francese, said if condom lubricant could be detected in fingermarks it would improve the evidence for the prosecution by establishing the assailant's presence at the scene and, crucially, having had contact with a condom.
"This would enable forensic scientists to provide further support to the evidence in alleged cases of sexual assault," she said.
The findings were published in the journal Rapid Communications in Mass Spectrometry.