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Pioneering forensic technique could bring more rapists to justice

police
police

A pioneering new forensic technique that could help bring more rapists to justice, even when they use a condom, has been developed by British scientists.

While DNA technology allows police to identify attackers in most cases, investigations can be frustrated if the assailant has used a condom.

But now scientists at Loughborough University have developed a method of confirming that a condom has been used and even identifying the type and brand.

The development could signal a major breakthrough in the way some sexual offences are investigated and could also help improve poor prosecution rates.

The technique uses a small needle surrounded by a solvent to collect minute chemical traces from a crime scene or victim.

Scientists then use mass spectrometry to identify a chemical fingerprint belonging to the type of condom.

Stephanie Rankin-Turner, a postdoctoral research associate, who helped develop the technique said she hoped the work would see more attackers brought to justice.

She said: “As more perpetrators of sexual assault crimes are using condoms to prevent leaving behind DNA evidence, trace residues from the condom or any lubricants used may be left behind.

“The ability to detect these traces could be useful in confirming that a condom was used and potentially providing information as to the type of condom used.

“Although this evidence can't identify the offender in the same way DNA evidence can, it can still provide chemical evidence that could prove incredibly valuable to an investigation in the absence of biological evidence.”

Using the same technique, scientists have also developed a way of detecting, gathering and identifying semen from a crime scene more quickly and reliably.

Ms Rankin-Turner said the breakthrough would help speed up the process and lessen the victim’s anxiety of waiting to know if there was DNA evidence available.

She said: “This technique was developed to provide a faster and more reliable means of analysis, with the ultimate aim of speeding up investigations.

“Evidence backlogs have been a major problem in the past, with samples sitting in evidence lockers waiting to be analysed.

“By allowing investigators to quickly confirm whether or not a substance is semen, the time spent waiting for analysis of potential semen samples can be reduced, ultimately speeding up an investigation.

“Long, drawn-out investigations can obviously be very stressful to victims, so we want to provide technology to make investigations and evidence analysis more efficient”

The team at Loughborough believe portable kits could be developed allowing police officers to carry out analysis at a crime scene or police station without having to send the samples off to a laboratory.

Prosecutors are under increasing pressure to improve the number of successful convictions after the latest figures revealed that they had hit a record low.

In 2019-20, 1,439 suspects in cases where a rape had been alleged were convicted of rape or another crime - half the number three years ago.

The Crown Prosecution Service (CPS) has announced a five year blueprint to try to improve the number of successful prosecutions.