Since 2nd March 2015 in the UK it has been an offence for a driver to have in excess of 2µg of Delta-9-tetrahydrocannabinol (THC) per 100ml of blood. THC levels above this limit are considered to be a positive test and will very likely lead to prosecution.
UK Police have the power to conduct a roadside swab test for cannabis on any driver they suspect of having THC in their system. Either saliva or sweat can be tested and a positive test will result in the driver being arrested on “suspicion”.
A blood sample for evidential purposes will be taken at the police station.
In court, the prosecution does not have to prove that a person’s driving was impaired, the presence of THC in excess of the prescribed limit is sufficient evidence. The minimum penalty upon conviction is to be disqualified from driving for one year and a fine up to £5,000.
Drivers who are prescribed Sativex have a medical defense. However, how the plant derived THC in Sativex is any different from THC in a joint escapes me.
A recent study demonstrating that cannabidiol (CBD) can be converted by the gastric system into tetrahydrocannabinol (THC) could be a potential defense in court.
“It is still not clear whether the human stomach can convert CBD into THC, but this study provides important confirmatory evidence that this may be the case,” says Editor-in-Chief Daniele Piomelli, PhD,University of California-Irvine, School of Medicine.
The findings of this study are from conclusive, however the possibility that CBD can be converted to THC in the body could be used as a defence as it raises “reasonable doubt”
NOTE: If you admit to smoking a cannabis joint then there is no “reasonable doubt”, and if you don’t feel confident in answering a police officer’s questions, remember you have a right to silence.