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DNA Lab Blunder

By Louise Shorter on 01/04/12

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DNA Lab Blunder

From Inside Time April 2012

A man in court on a rape charge had his trial abruptly halted when it was revealed that a forensic blunder very nearly had him imprisoned for a crime he did not commit

Adam Scott from Exeter, Devon lived 190 miles away from the scene of a rape in Manchester but when police were told by LGC Forensics that crime scene DNA had produced a hit against Scott’s own DNA profile, he was arrested and charged. Scott vehemently denied ever having been to Manchester. New tests of the original crime scene sample by scientists at the lab, the second time did not match to Scott. Human error had led to the contamination.

In a statement, Scott said: “I am angry that I was falsely accused. I am angry about the amount of pain it has put me and my family through. I sincerely hope that justice comes for the victim and that the true rapist is caught. I am disgusted that it has taken this long for them to work out what went wrong.”

Sources told The Guardian newspaper, which exposed the contamination, that Adam Scott was unknown to the police team investigating the crime before the lab claimed they had a 1 in a billion DNA match to him. LGC Forensics told Inside Time “the root of the contamination was human error in the incorrect re-use of plastic trays as part of the robotic DNA extraction process.” It appears Mr Scott’s DNA profile was found in a crime scene exhibit from an unconnected charge of affray which was being processed in the same laboratory that was examining the crime scene stain from the rape.

The affray crime scene exhibit which contained Mr Scott’s DNA had been processed in a plastic tray which was then erroneously reused for a new, separate testing of the rape scene exhibits, giving the false illusion that he had been at both crime scenes. Mr Scott was later convicted of the affray charge but, as has now been proved, had not committed rape.
The lab at the centre of this storm added “new processes have been introduced to prevent such an error happening again and 26,000 samples that have been processed since the robotics were introduced in March 2011 have been checked to ensure they had not been contaminated. This checking is now complete and no other cases of contamination have been found.”

Yet, Adam Scott is not the first to be up against the perceived infallibility of DNA evidence. Cold case reviews of unsolved crime scene stains have led to celebrated high profile convictions but this apparent ‘barcode indicator of guilt’ is not without criticism.

Inside Justice was established in 2010 to assist prisoners who protest their innocence. So far, we’ve been alerted to 290 claims of innocence.
Three of our cases have worrying echoes of this latest case of false evidence. All are rape cases and none would have reached court
without the DNA evidence. All the men involved have no similar offending behaviour or apparent escalation of crime type leading up to a stranger rape. But the difficulty these convicted men face is proving contamination has occurred if indeed it has if the samples have been destroyed and there is no opportunity left to run a new DNA test on a retained, untested, section of a crime scene exhibit.

Establishing whether any material has been kept in archives has always been an uphill struggle for any prisoner, post conviction, as
described previously in Inside Time, and it has just become harder still. The closure of the Forensic Science Service (FSS) last month has
led to fears that already hard to access, postconviction, crime scene samples and files will become impossible to gain access to now the
laboratories and scientists no longer exist.

A letter to a firm of solicitors, seen by Inside Justice, from Chief Scientist Dr Chris Howden sets out that now the FSS has closed, all files and retained materials have been sent to a central archiving facility in Birmingham. This facility has been renamed the “Forensic Archive” and is now managed through the Home Office. Dr Howden states that prisoners and their legal representatives will no longer be able to request access and writes “it will not be possible for you to make an application for material directly to the Forensic Archive.”

He continues “applications for retrieval of materials will now only be accepted by the Police and other law enforcement agencies, the Crown Prosecution Service, the Criminal Cases Review Commission and the Independent Police Complaints Commission.”

It is understood the Association of Chief Police Officers has provided assurances that materials relating to serious offences will be retained for 30 years and less serious offences for up to 7 years.