NORML supports efforts to reduce impairment on the roads, and our own “Principles of Responsible Cannabis Use” invoke a no-driving clause. However, like with alcohol it is important to distinguish between use and impairment. Furthermore, efforts to reduce the use of drugs may actually backfire by encouraging more use of alcohol, a far more dangerous substance that encourages risk-taking behaviour.

“The New Zealand Transport Agency (NZTA) has this week begun a series of television advertisements that purport to show the reactions of secretly filmed New Zealanders when they are told the driver of the car they are in is high on drugs,” says NORML spokesperson Chris Fowlie.

“What they don’t show is that emerging scientific research indicates that cannabis actually has far less impact on the psychomotor skills needed for driving than alcohol does, and is seldom a causal factor in automobile accidents.” (click here for NORML’s research base on drugs and driving)

Furthermore, a recent study examining road deaths in US states that allow access to medicinal cannabis compared to those that maintain a tough prohibition found the medical states had lower rates of automobile deaths. Researchers said this may have resulted from more drivers choosing to use cannabis and correspondingly fewer drivers using alcohol.

“The risk for NZTA is that if their anti-drug campaign is too successful they may inadvertently encourage more drivers to drink and cause more road crashes”

In the end, says NORML, concerns regarding doped driving should not be an impediment to marijuana-law reform. Alcohol is legal, yet society maintains tough laws punishing those who choose to drive impaired by it. There is no reason why similar principles should not regulate cannabis consumption.

The key is having laws that punish impairment, not just use.

Current law in New Zealand is that it is illegal to drive with any trace of illegal drugs in the system, yet traces of cannabinoids may linger in the blood for several days, long after any impairment has worn off.

In contrast to this approach, a recent European meta study of drug-driving research, published in the journal Addiction, found a THC blood serum concentration of 7-10ng/ml “correlated with an impairment comparable to that caused by a blood alcohol concentration (BAC) of 0.05%. Thus, a suitable numerical limit for THC in serum may fall in that range.”

NORML believes a level such as this should be set so that impaired drivers are effectively detected, and non-impaired drivers are not unfairly punished.