Ten thousand criminal cases in England and Wales are being reviewed after it emerged that data at a forensic laboratory in Manchester may have been manipulated, causing the biggest recall of samples in British criminal justice history.



A minister said the alleged data manipulation was discovered in 2017 at a lab run by Randox Testing, but the Guardian can reveal that warnings about the lab run by a predecessor company date back to 2012.

Nick Hurd was forced to issue a statement acknowleding “the potential impact on public confidence” in forensic science of the revelations, while police said two cases involving road deaths had been referred to the court of appeal and about 50 prosecutions of drug-driving had been discontinued.

Those alleged to be involved in the scientific work under scrutiny had previously worked at a different firm, Trimega, which was criticised for the quality of its work in court judgments dating back to 2012. It was bought by Randox, and two senior Trimega employees were taken on in influential positions.



In 2012, an open judgment criticised Trimega for wrongly informing a court that the mother of a three- and four-year-old had been using increasing amounts of cocaine and opiates as as she fought to keep her children.

The court was told that following its error, Trimega had withheld an apology to the mother because it feared rivals would exploit it for commercial advantage.

“In this respect, Trimega’s attitude does no credit to an organisation entrusted with the responsibility of providing independent expert advice to the court on matters that will affect the lives of children and families,” the judgement states.

Mr Justice Jonathan Baker told the high court the children would have gone into care had the sample not been checked by another lab. He warned at the time: “Erroneous expert evidence may lead to the gravest miscarriage of justice imaginable – the wrongful removal of ­children from their families.”

In 2013, Trimega was criticised for incorrectly reporting that a mother’s blood -alcohol test was consistent with “heavy drinking”; in fact, it had been consistent with abstinence. The company only identified the mistake once it learned that the result had caused the local authority to withdraw its support for a plan to return the mother’s one-year-old child to her care.

Concerns emerged about Randox in January this year and a criminal investigation was launched that led to Tuesday’s announcements. The investigation then spread to encompass the former Trimega lab, which focused on child protection and family court cases.

Police said two people had been arrested and five more had been interviewed under caution. All worked at Randox and some had previously worked at Trimega, according to James Vaughan, of the National Police Chiefs’ Council, who is overseeing the police response.

Julia Mulligan, who leads on transparency and integrity for the Association of Police and Crime Commissioners, which oversees police forces in England and Wales, said: “Understandably, confidence in the criminal justice system will be rocked, but I am confident that chief constables and the CPS [Crown Prosecution Service] in particular are doing everything they can to deal with this unforeseeable challenge, affecting both live and historic cases.”

Three-quarters of the cases being reviewed were traffic offences, such as drug-driving, in an exercise that may take three years to complete. The rest include violent crime, sexual offences and unexplained deaths, with no impact found so far in the most serious cases.

Gillian Tully, the forensic services regulator, said: “In terms of the number of cases, it is certainly the biggest thing I am aware of in this country.”



She said extra checks on other forensic providers had not highlighted concerns elsewhere.



The current government abolished the main forensic provider, the Forensic Science Service, in late 2010, with the intention of creating a market where independent companies competed for business. It ceased to operate in 2012.

Louise Haigh, Labour’s shadow policing minister: “It is clear the chaotic reorganisation of the forensics system, including the closure of the Forensic Science Service, has left providers who were simply not fit for purpose to fill the gap. This has had devastating consequences.”

She said she was concerned that Hurd did not appear to know there had been issues about one of Randox’s predecessor companies from previous years.



“It is deeply concerning that the Minister would issue a statement that didn’t appear to include the full facts. Those affected and the public at large have a right to know the truth about this scandal.”