AROUND a quarter of drug-driving cases which could not be prosecuted because of toxicology backlogs involved potential repeat offenders, new analysis shows.

More than 5600 drug-driving blood samples have been tested since new legislation was introduced in 2019, which made it an offence to drive while under the influence of drugs including cocaine, morphine and cannabis.

As of May this year, 384 cases could not be prosecuted because they had reached the statutory 12-month time limit due to a delay in forensic testing, the Scottish Police Authority (SPA) said.

Fiona Douglas, director of forensic services at the SPA, told a meeting of the organisation that 99 of the missed cases involved a potential repeat offender with analogous or previous convictions.

READ MORE: Forensic labs forced to outsource drug driving tests to meet demand

However, due to the processes in place to prioritise the most serious cases, none of the cases involved fatalities and just two involved an injury, the latest report shows.

She called for long-term measures to fix the backlogs and said current methods, including outsourcing, are a “sticking plaster” amid high demand.

Initial reports for the period from May 21 to June 30, 2022, indicate that a further potential 49 cases cannot be progressed, with another 11 cases for the whole month of July.

Douglas said an agreement is being finalised to outsource the forensic contract with private firms after the Scottish Government agreed to fund a further £370,000.

The funds will be spent between September and March 2023.

She said outsourcing will help alleviate some of the pressures from the “higher than predicted” demand for drug-driving and toxicology services in Scotland.

However, members of the authority, which holds Police Scotland to account, raised concerns about tackling the issue in the long term.

Douglas said: “I think it’s important to note that these are sticking plasters that we are putting in place over the demand that exists for drug-driving toxicology analysis, which is far higher than expected since the legislation was implemented.”

She said the additional funding will go “some way to reducing and addressing the backlog situation that I’ve been reporting into the authority”.

READ MORE: Murder inquiry launched following Grangemouth death

She added: “There is a need for a long-term, sustainable solution for the delivery of toxicology analysis and work has been done and is with the Scottish Government with regards to options for what that… model could look like.”

The legislation was introduced in October 2019 and has seen Police Scotland start roadside mouth-swab testing for cannabis and cocaine on any motorist they suspect of being impaired.

It is a crime to drive in Scotland when over the limit for certain prescribed drugs. There is a zero-tolerance approach to driving after taking illegal drugs.