Why more than 1,700 drug-driving prosecutions could be overturned

The National Police Chiefs’ Council has announced that all drug-driving tests produced by Synlab between April 2019 and December 2020 have to be withdrawn

The Crown Prosecution Service is contacting those whose samples have been withdrawn (Getty Images)

More than 1,700 drug-driving prosecutions have been thrown into doubt after a review found the results of hundreds of lab tests were wrong.

Problems with tests carried out by Synlab Laboratory Services Limited were identified by the company in December 2020 and a review by police and the forensic science regulator has now found several hundred results will have to be withdrawn as evidence.

On Monday, the National Police Chiefs’ Council (NPCC) announced that all drug-driving tests produced by Synlab between April 2019 and December 2020 where levels were found to be above the prescribed limit must be withdrawn.