FORENSIC breakthroughs have helped to secure more than 500 years' jail time for offenders convicted of rape and serious sexual assaults.
A West Yorkshire Police team was set up 20 years ago - in October 2004 - to investigate non-recent sexual offences.
Since then, it has helped to bring about more than 100 convictions for such crimes, including in the Bradford district.
Codenamed Operation Recall, the dedicated West Yorkshire Police squad is part of the force's Major Investigation Review Team (MIRT).
Detectives work closely with experts at Eurofins Forensic Services to best use advancements in DNA technology to progress investigations into non-recent cases of rape and serious sexual assault.
The team predominantly relies on materials and paperwork retained by forensic scientists from their original examination of exhibits.
They are currently investigating around 80 offences, with some dating back as far as 1974.
"Forensic science is continually developing and allowing us to make advances in investigations where we were unable to do so before," said Detective Sergeant Richard Ord, of the MIRT.
"We consult with the scientists to see what can be done to establish a DNA profile from evidence that was sometimes captured decades ago.
"In most of these cases, the forensic science was not advanced enough to get a DNA profile at the time the offence was committed or reported to us."
When the team gets a DNA profile, detectives work to try and find a match on the national DNA database.
This contains millions of DNA profiles of offenders which have been collected by UK police over the years.
Past cases covered by the Telegraph & Argus
In 2006, the Telegraph & Argus reported how work by Operation Recall detectives in Bradford led to 10 years' in jail for a 44-year-old Keighley man who had "brutally" raped a mother in 1989.
Martin Done was caught after his DNA linked him to the sex attack on the 22-year-old mum of a six-week-old baby in her home.
He sneaked into her home wearing a Ku Klux Klan-style hood with diamond-shaped eye holes and threatened her and her baby with a knife.
Done, a band-knife operator who was living in Ingrow at the time, was arrested in June 2005 after the Operation Recall detectives made a "hit" on the national DNA database.
At the time of his conviction, Detective Superintendent John Parkinson said it was advances in DNA technology that had led detectives to Done and in securing the verdict.
He praised the victim - who cannot be named for legal reasons - for showing great perseverance with the investigation, and her courage and dignity.
He said the case demonstrated the importance of their work, adding: "It sends a very important message to offenders that we don't forget, we never give up and they must be looking over their shoulders to see if we are going to knock on their door.
"With every new advance we come a step closer to catching those responsible for the most serious crimes."
At the time, Judge Stephen Ashurst said but for the diligence of police officers, the crime may have remained undetected.
He told Done he would be put on the sex offenders' register for an indefinite period.
Meanwhile, in 2010, 48-year-old paedophile Terry McVicar was given a life sentence for child sex offences committed in 1990.
McVicar kidnapped a four-year-old girl from a playground in Bradford and took her to his bedsit in Undercliffe, where he subjected her to prolonged sexual abuse.
After the case was reopened, forensic scientists used advances in DNA technology to link McVicar to the crime through a hair from the victim's clothing.
'We never give up on seeking justice'
Det Serg Ord said: "We're very proud of what we've been able to achieve as part of Operation Recall.
"It was established back in 2004 so that we could take full advantage of scientific progress to seek justice for our victims.
"As officers we never give up on seeking justice for victims, so the opportunity to further investigate cases like this has been a real benefit to us.
"Sometimes it's a case of waiting for the science to catch up with us so that we can deliver justice for victims.
"And I have no doubt there will be further scientific developments in the coming years."
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