Forensic testing for crime scene DNA has improved massively, a jury has heard, since a man was wrongly jailed for a 2003 rape in Salford.
Andrew Malkinson was jailed the year after the attack and spent 17 years behind bars, after he was picked out in an identity parade in error by three witnesses, even though none of his DNA was found linking him to the attack in Little Hulton.
The rape victim, a woman in her 30s, had been dragged from the street beside a motorway embankment, brutally beaten and raped twice, in the early hours of July 19, 2003.
A DNA sample was later recovered from clothing of the victim in 2007, which was not linked to Mr Malkinson, and the source was designated “Unknown Male 1”, Manchester Crown Court heard.
This discovery “ought to have set alarm bells ringing” the court has heard, but it was only in 2022 that police matched the DNA sample left on a vest top of the rape victim, to the DNA profile of the defendant, Paul Quinn, a man who lived less than a mile away from the crime scene at the time of the attack.
Quinn, 51, denies the attack.
Emma McCarthy, a forensic scientist and DNA and crime scene expert, said a sample from a vest top worn by the victim was tested in 2003, and no DNA present was linked to Mr Malkinson.
Ms McCarthy told the jury: “Because we know techniques, and our techniques have improved massively in 20 years, we re-extracted to see if we could remove any more DNA.
“We know all of our techniques have improved, our way of recording DNA is better. Also, testing is much more sensitive.”
Jurors heard later that testing of DNA recovered from the victim’s vest top estimated the findings would be at least one billion times more likely if Quinn’s DNA was a contributor to the sample, than if he was not.
Ms McCarthy, asked to quantify the statistics, said, as a comparison, a million seconds amounts to about 11 days, while a billion seconds amounts to 35 years.
Earlier, John Price KC, prosecuting, told jurors the emergence of DNA evidence linking Quinn to the attack had been a “slow burn” process over the years, as techniques had developed.
Mr Malkinson, now 60, and originally from Grimsby, Lincolnshire, was released from jail in 2020.
He had made multiple appeals for authorities to review his case before his final attempt led to his appeal against his conviction being granted by the Court of Appeal.
Father-of-five Quinn, who moved from Salford to Exeter, Devon, after he separated and divorced in 2016, has pleaded not guilty to two counts of rape, grievous bodily harm and attempting to choke or strangle his victim to render her unconscious while he carried out the attack.
The trial was adjourned until Monday.
By Pat Hurst, Press Assocaition.
