The number of drug driving charges has risen by 125% to record levels in the last year. The significant rise in the number of charges was found after a Freedom of Information (FOI) request to police forces by to investigate the impact of new drug driving laws introduced five years ago. Of the 27 police forces across England and Wales that responded, the total number of charges increased from 4,122 in 2015/16 to 9,270 in 2019/20.

The below infographic shows how the number of charges in each of these forces has fluctuated between 2015 and 2020.

Notably, forces in Essex, Merseyside and West Yorkshire have seen steep increases in drug driving charges in recent years. Essex police charged the most people for drug driving in the last year, with 1,828 charges between March 2019 and February 2020, while Merseyside Police had the second highest number at 1,605.

While most forces have seen an increase in the number of charges between 2015/16 and 2019/20, others have seen notable decreases.

For instance, the Metropolitan Police saw a peak number of charges in 2016/17 of 1,152 but this has since decreased to just 339 charges in 2019/20. Sixteen police forces also provided data on the number of drivers who had tested positive for drug driving at the roadside, with the cumulative number of positive tests in these areas more than tripling from 2,619 in 2015/16 to 9,074 in 2019/20.

Not all positive tests necessarily result in the driver being charged, for instance where a roadside test shows as positive, but a police station test comes back as negative.

Drug driving became a specific offence in 2015, meaning police could charge someone for drug driving if they had at least one of 16 specified drugs in their blood above a certain limit. Half of the 16 drugs listed are ‘medicinal’ and so drivers are just as likely to be prosecuted for having a legal drug in their system as they are an illegal drug whilst behind the wheel.


Legal Medicinal Drugs
Drug Blood threshold limit (mg/L)
Clonazepam 50
Diazepam 550
Flunitrazepam 300
Lorazepam 100
Methadone 500
Morphine 80
Oxazepam 300
Temazepam 1000


Illegal Drugs
Drug Blood threshold limit (mg/L)
Benzoylecgonine 50
Cocaine 10
Cannabis 2
Ketamine 20
Methylamphetamine 10
Heroin 5


Drugs that drivers can be charged for if found to be above the specified limit. Data sourced from: Head of Marketing, Jessica Potts, said: “Most people are aware of the ongoing problems surrounding drink driving but far fewer people know that drug driving is just as much of a problem. “Although the data suggests the new police powers are enabling forces to arrest and charge more people, it’s alarming that the overall number of drug driving charges continue to rise despite its potential to cause devastating outcomes.

“Motorists should be especially aware that the law doesn’t just apply to illegal drugs. Medicinal drugs, such as those prescribed to treat insomnia or even some pain killers, feature on the list so it’s crucial drivers always check their medication to see if it impairs their ability to drive.”