Drug driving: use of legal limits

Guidance on using legal limits in the prosecution of drug-driving offences.


Section 5A Road Traffic Act 1988 created an offence of driving a motor vehicle while the concentration of any specified drug in the blood is above a limit set for that drug. The limits for a number of drugs have been established by regulations under the act.

The regulator has issued guidance on the use of the limits in contexts other than the investigation and prosecution of offences under s5A.