Unreliable Drug Samples Produced in Drug Drive Cases

When a driver is suspected of Drug Driving, a roadside swab may be used an a preliminary test, followed by a blood sample which is analysed and reported.

Drug driving laws were tightened in April 2015, when a specific offence of driving over a prescribed level of drugs came into effect, alongside the older offences of driving whilst unfit through drugs. It became a criminal offence to have more than minimal prescribed levels of certain drugs and their by-products in your blood. The list of drugs can be found on the government website here .

One of the laboratories used to analyse the blood samples was Synlab. In December 2020, Synlab reported an issue in and stopped processing all further samples. This led to a review in 2021, which included Police, Home Office and Prosecutors, to decide how likely it was that prosecutions and investigations had been, and would be affected

The National Police Chiefs’ Council (NPCC) and the Forensic Science Regulator (FSR) have now concluded their reviews into Synlab’s analysis of drug driving samples with worrying conclusions about the quality assurance process, which safeguarded against inaccurate or misleading results.

It has been agreed that all results produced by Synlab between April 2019 and December 2020, where a positive result was reported (above the limit) must be withdrawn as evidence. No evidence was found during the review of any malicious intent but that makes it none the less worrying.o

During the first half of 2021 the results were subject to initial reviews and these led to a number of them being rescinded. In September 2021, the NPPC and partners, instructed a further significant review of Synlab’s processes and data for the remaining results. The findings of this work concluded that the analysis and processes were not conducted to the appropriate standard and as a result the remaining evidential results also needed to be withdrawn.

Between April 2019 and December 2020, Synlab undertook Section 5A drug drive analysis of 4,255 samples. Of these samples:

• 2,181 had a negative report of no drugs or below the prescribed limit.

• 296 samples were from cases with a positive result but no conviction.

• The remaining 1,778 samples had drug levels reported by Synlab as above the prescribed limit resulting in successful prosecutions. They are now reported to have been rescinded, which would involve applying to re-open convictions. Drivers will still have suffered periods of disqualification, impact of conviction and sentence on work and family life.

National Police Chiefs’ Council Lead for Forensics, Chief Constable Nick Dean, said:

“This has been a lengthy and in-depth review, which I know has been hugely challenging for those individuals who are impacted by the results. I would like to commend their patience while we have worked through the data. The reviews were done, at such a detailed level, because we are committed to ensuring evidence entering the courts is reliable. We take any issues seriously and wanted to ensure due diligence was taken to achieve the correct outcome.

“Synlab have been very forthcoming and open during the reviews, which we welcome. I want to thank all our partners who have spent many hours reviewing and working hard to try and get this right.

“It is hugely regrettable, whenever evidence that has been submitted to the courts in good faith has to be withdrawn.  We know that this will have significant knock-on effects for people. The CPS have been or will be contacting all those whose samples have been rescinded.”

This is the final outcome and marks the conclusion of the NPCC led review.