Scientists from the University of San Diego in California have published a study that found that being under the influence of cannabis is not associated with poor driving performance.
Released May 26, the study was funded by the state of California and used specially trained law enforcement officers.
After consuming cannabis via a “cannabis cigarette” containing 5.9% THC or 13.4% THC, or a placebo, the 191 participants assessed their ability to drive via a simulator driving, a real car, and were also subjected to Standard Sobriety Tests (SSTs) by specially trained police officers.
Saliva samples were taken at the same time as driving was assessed, including the ability to sit upright, over a 5-hour period.
Although field sobriety tests conducted by police officers correctly identified participants in the cannabis control group in 81% of cases, they also incorrectly identified 49% of participants in the placebo group as being intoxicated, suggesting a lack of reliability of the tests carried out by the police. Officers performed several tests, including walking and turning, a Romberg test, or standing on one leg and putting their finger to their nose.
The researchers’ analysis of participants’ mouth swabs, blood samples, and breath after using the car and simulator found no link between substandard driving and fuel consumption. cannabis.
The researchers stated in their study: “In the largest trial to date involving experienced users smoking cannabis, there was no correlation between THC (and related metabolites/cannabinoids) in blood, oral fluid or breath and driving performance. The complete lack of relationship between the concentration of the centrally active component of cannabis in blood, saliva and breath is strong evidence against the use of laws per se for cannabis.
These findings are consistent with a recent meta-analysis that found THC levels to be “relatively poor predictors of cannabis-induced impairment.”
