Convictions in doubt as data manipulation claims hit lab run by Northern Ireland company
Scores of prosecutions across the UK have been dropped and several convictions hang in the balance after 10,000 potential cases of data manipulation were identified at a forensics lab run by a Northern Ireland company.
The National Police Chiefs' Council (NPCC) said forensic tests across 42 police forces, including some relating to rape and murder cases, were being considered possibly unreliable and needed re-examining.
Three-quarters of the cases were traffic offences such as drug driving - with the rest including violent crime, sexual offences and unexplained deaths, dating back to 2013.
Toxicology tests are carried out to detect the presence of drugs or alcohol in someone's hair, blood or urine and can be relied on as evidence in court.
As a result of the suspected breach in standards, around 50 drug driving investigations have been discontinued, while two road death convictions have been referred to the Court of Appeal.
Retests have so far found no impact on cases of sexual offences, violence or murder, the NPCC said.
The Forensic Science Regulator said that in terms of numbers of cases, it was the biggest issue of its kind ever to happen in the UK.
Two men have been arrested and five interviewed under caution by Greater Manchester Police over the alleged manipulation by individuals working at a Randox Testing Services (RTS) site in Manchester.
The alleged misconduct emerged earlier this year when a data anomaly in a drug driving case was reported to RTS.
RTS is based in Crumlin, Co Antrim, and has offices in London and Manchester.
Deputy Chief Constable James Vaughan, the NPCC forensic expert, said: "This is of grave concern to me, it is of great concern to policing and our partners in criminal justice, and we are taking it extremely seriously and provided a nationally co-ordinated and very swift, robust response, to understand more detail."
"Forensic science in criminal justice is paramount and vital to confidence in the criminal justice system."
Potential data manipulation at a separate facility, Trimega Laboratories, is also being investigated by Greater Manchester Police - affecting child protection and family court cases, the NPCC said.
It is understood the two suspects arrested in connection with the alleged malpractice also worked for Trimega.
All 50 drug driving offences which were dropped had been due to go on trial, Mr Vaughan said. Some were discontinued because there was no sample available for retesting, the sample was insufficient in quality or quantity to allow retesting or there had been degradation of evidence.
Not every court was sympathetic to requests for proceedings to be adjourned, leading to further cases to be ditched, he said.
The NPCC revealed retesting was either complete or under way for around 70% of the 900 highest priority cases, with the rest expected to be completed by mid-2018.
These include live investigations approaching or in trial, those convicted but not sentenced, those bailed in advance of trial or sentence, and convictions where the defendant was in prison. A total of 275 murders and around 900 rape cases are being reappraised.
RTS's Manchester lab had its accreditation suspended on March 21 and has voluntarily suspended accreditation at its Northern Ireland site.
RTS Toxicology manager Dr Mark Piper said: "We will do all that we can to ensure this situation is resolved and deeply regret the distress that has been caused."