When implementing its topics, the federal government’s traffic light shows red more often than green. In the coalition agreement, for example, it was agreed that cannabis should be sold to adults without being punished. But although a draft law is in the drawer, politicians and scientists continue to discuss the limit values for the active ingredient in hemp, THC (tetrahydrocannabinol), the amount you own and the risk of accidents on the road. Because new studies on pot smoking drivers are alarming.
“There are initial findings from the USA that traffic accidents have increased after legalization,” says Dieter Müller, a professor at the Saxon Police University. For example, the state of Washington allowed the free trade in cannabis. “There, the proportion of drivers in fatal traffic accidents with THC in their blood increased from 9.3 percent before legalization to 19.1 percent,” says Müller. He doesn’t want to make a forecast for Germany because “other studies show the opposite”.
Zero tolerance for stoners
Around four million Germans use cannabis occasionally. While drivers are allowed to drive intoxicated with an after-work beer up to the 0.5 per thousand limit, the zero-tolerance limit applies to potheads after an after-work joint: Even one nanogram of THC per milliliter (ng/ml) of blood leads to a notification to the road traffic authority , driving license withdrawal and an expensive MPU (“idiot test”) threaten.
“The research and knowledge base on the influence of cannabis on German traffic is thin.”
Prof. Dr. Dieter Müller, University of the Saxon Police
A study at the Institute for Forensic Medicine at the University Hospital in Düsseldorf shows how illegal potheads behave in traffic. There, 4350 traffic controls by stoned drivers were evaluated. The main finding of the physicians: The breakdown of the THC active substance and its by-products is less predictable than with alcohol, critical states can still be expected many hours after cannabis consumption. Driving simulator studies showed that anyone who gets behind the wheel immediately after a joint makes various driving mistakes. After three hours the intoxication is gone, but after six hours the error rate increases again.
Experience seems to make up for cannabis-related deficiencies
The group of young people in particular, with their already increased risk of accidents and greater openness to drugs, is a cause for concern. For under 25-year-olds, a zero-tolerance solution should apply, regardless of all limit value discussions, the doctors demand. Interesting: More than half of the over 35-year-olds who were caught at the controls were driving inconspicuously. Experience seems to be able to compensate for cannabis-related deficits.
Even a THC content of 3 to 4 ng/ml in the blood should correspond to the 0.5 per mil limit for alcohol. Another very recent study of stoned drivers causing road accidents with injuries comes from Canada. According to this, after the legalization of cannabis, the number of drivers who had more than 5 ng/ml THC in their blood tripled. Traffic lawyer Müller calls for further research: “Otherwise the possible consequences for traffic safety are incalculable.”
