In the course of the planned legalisation, the traffic light coalition, in addition to the equally important demand for the legalisation of home cultivation, also has no choice but to introduce an adequate solution for driving cannabis in road traffic.

But how a reasonable and sensible (limit) regulation in driving licence law should look like is a controversially discussed question which is by far not as trivial to answer as with a regulation similar to the alcohol limit.

A "zero tolerance" policy makes little sense, because someone who smokes a dowel on Friday is fit to drive again on Monday and still runs the risk of losing his driving licence because of detectable degradation products in the blood, which ultimately do not allow any scientifically tenable conclusions about the user's fitness to drive.
In the case of cannabis patients, as Georg Wurth of the German Hemp Association recently reported in an issue of DHV News on YouTube, it is assumed that regular and constant use would quickly lead to a high tolerance on the part of the user, which would no longer allow any restriction of driving ability to be expected.

In the case of so-called recreational users, on the other hand, the alarmingly low limit of 1 nanogram THC per millilitre of blood is often enough for the delinquent to be confronted with the accusation of not being fit to drive and the consequences that usually follow under driving licence law.

The very strange development of tolerance inherent in cannabis, according to the motto "less is more", does the rest to make finding a sensible regulation of the driving licence problem more difficult. It has been proven that people who smoke pot a lot and regularly have very little to do with driving failure. In Germany, cannabis patients are not per se denied the right to drive on the basis of medical use under certain conditions, such as controlled and regular use in accordance with a doctor's prescription.  

On the other hand, those who only occasionally enjoy a fat sports cigarette are sometimes so pressed into the couch that driving a car is out of the question. In this state, some people are happy to somehow make it to the fridge in the kitchen to fight the emerging binge. And this is exactly where the dilemma in the issue of driving licences comes from. Even in the USA, the motherland of prohibition, driving under the influence of THC is a controversial topic and each "legal state" seeks and finds its own ways of dealing with cannabis in road traffic. Some states in the USA, such as Colorado, have set limits for THC and its metabolites in the blood, which can cause serious problems if exceeded.

In California, on the other hand, there are no official limits for THC in the bloodstream. The Cali cops use the same testing methods as in Germany, such as checking the pupil reaction, to determine whether the driver's ability to drive is impaired (possibly due to cannabinoids). When the legalisation of adult recreational use was passed in California, the California legislature simultaneously created a Task Force on Impaired Driving to address the issue of driving under the influence of cannabis and to discuss sensible regulations for dealing with drivers with an affinity for cannabis.

The expert panel, led by the Highway Patrol, came up with a completely new way of looking at the issue and, surprisingly, recommended that California lawmakers completely abandon the idea of setting a fixed limit for THC or its breakdown products in the blood, as can be read in an article on

According to the article, the expert panel concludes that such limits are not scientifically tenable. In reality, the driving ability of Californian road users is also checked on the spot with the usual sobriety tests in order to determine any impairment due to cannabis consumption. Here, however, the cops could definitely be trained a little more and better, the task force members said in their remarks.

Blood tests are also inherently flawed and unsuitable for determining acute driving (un)fitness, especially since blood values do not allow conclusions to be drawn about the time of consumption, nor the individual tolerance level of a cannabis user. In short: THC levels in the blood are no way to measure how stoned someone was or is at a certain point in time.

The recommendation of the expert group is therefore to completely dispense with a THC limit value regulation and to provide the law enforcers exclusively with scientifically doubtless methods for determining possible, drug-related restrictions on fitness to drive. What methods the ladies and gentlemen have in mind, however, they left completely open. Unfortunately, it is also still unclear what solutions our new federal government is striving for in order to put an end to the prevailing abuse of the driving licence law as a quasi-substitute criminal law in the course of legalisation in favour of a fair and sensible regulation. In any case, the findings of the Californian experts should be taken into consideration.