Driving and Cannabis

Marijuana’s impact on driving has for a long time been under researched, there is of course ample evidence about the negative impact of drinking and driving but when it comes to marijuana there seems to be a lack of research.

One article for instance claimed that by smoking marijuana your chances of having an accident increases by double or even triple. The study that the article was based on took into accounts all accidents where THC was found in the blood of the driver that includes those who have taken both alcohol and marijuana.

The effects of marijuana on driving have been reported to include:

1. Compensation: Most marijuana smokers realise that their ability is impaired and therefore compensate by driving slower.
2. Impairment of “Road-tracking performance” this however is not unusual ‘compared to many medicinal drugs'’
3. Increased reaction times
4. Inability to maintain headway

The fact that marijuana smokers are aware that their driving may be compromised means that unlike those who have drunk too much they actually compensate by slowing down and being more careful. This compared to people who drink and drive where the opposite effect can generally be observed with drivers with high blood alcohol content being overconfident and more reckless.

From the research done on marijuana and driving there seems to be two different opinions some have found that marijuana has a negative impact on driving and could potentially cause accidents however they also found that alcohol is far more dangerous and a larger contributing factor in crashes. Others (though they are a minority) have found that marijuana is not associated with accidents and in some cases may (due to people high being more cautious) be less accident prone than sober drivers.

One thing that must be taken into account is also the fact that marijuana is often not the only substance found in accident victims often alcohol is found the systems of accident victims. Alcohol causes reckless behaviour and has been proven to be a contributing factor in accidents so in accidents where marijuana and alcohol are both found in the system of a person in an accident it is more likely that alcohol is the problem.

There is also the apparent positive indirect impact marijuana has on accidents, one report which was released near the end of 2011 mentioned that states with medical marijuana had less accidents than states without medical marijuana. In states with medical marijuana there was a 9% decrease in accidents this was put down to the fact that those on medical marijuana are less likely to drink alcohol.

Even the US department of transport has it’s reservation about how much impact marijuana has on driving. In a report (The Incidence and Role of Drugs in Fatally Injured Drivers) by the US department of transport when it came to cannabis the report said that “In comparisons with the drug free drivers, statistically significant elevations in responsibility rates were found in drivers with alcohol alone and with all high-BAC-drug combinations. The responsibility rates of drivers with THC-only or cocaine-only were not higher than the drug free rates.”

This report seems to admit that the impact of accidents relating to cannabis consumption is limited. It does however point out something else and that is taking multiple drugs cannabis by itself might have less of an impact on driving but when taken with alcohol the effects can be damaging. Alcohol is known as a contributing factor in many accidents if cannabis and alcohol is found in someone’s body it doesn’t mean that cannabis was the cause of their reckless behavior it is more likely that it was caused by the alcohol. 

There is also evidence suggesting that anti-depressants can impact driving too one study by Ramaekers, Swijgman, and O'Hanlon hinted that some anti-depressants can impact driving with “impaired driving and tracking performance and decreased critical flicker fusion.” There are indeed many mind altering substances that are prescribed and yet it is still thought alright to drive with them.

In an ideal world people would not take drugs or drink whilst driving many substances can and do have an impact on driving legal and illicit, prescription and non prescription. The idea however that cannabis is a completely dangerous drug which rivals that of alcohol is however baseless and untrue.

As Robbe said in a paper in 1994 “the many psychotropic drugs, licit and illicit, that are available and used by people who subsequently drive, cannabis may well be among the least harmful.” There are many licit drugs which campaigners seem to forget when they aggressively focus on the detrimental impact of cannabis on driving. No one is denying the fact that cannabis does have some impact on driving but at the same time if cannabis is considered dangerous to drive with perhaps focus should be expanded.

For instance a Surrey University study in 1999 found that some anti-depressants can delay reaction times by up to twice that of someone with 80mg percent alcohol in their system. Another study by Dassanayake T, Michie P, Carter G, & Jones A in 2011 backed up the 1999 study by saying prescription drugs like Benzodiazepine increased the risk of a traffic accident by 60-80%!

So where exactly is the boundary drawn? As Robbe said many licit drugs impact driving more than cannabis yet no one makes a big deal about them. Surely if cannabis is considered a safety risk then prescription drugs which potentially have a bigger impact on driving should be investigated.

The question therefore has to be raised where is the boundary to be drawn? There is talk about a new drug-driving law in the UK.  No doubt cannabis would be considered a drug that will be actively cracked down on but will prescription drugs which have the same or more impact on driving be tolerated?

In all likelihood they will tolerate prescription drugs but won’t tolerate cannabis. It has been stigmatized by the decades of prohibition; it has been tarnished as an evil drug with terrible consequences. These claims that cannabis is deadly have no scientific backing whatsoever. Thousands die from alchohol each year while no one has ever died from cannabis consumption so how is it that alcohol is legal whilst cannabis remains illegal.

It is true that you prescription medicines are more of a necessity whilst cannabis is in general for recreational means. That however is not the point of this mini-rant it is more about showing how unequal and unscientific drug laws are. No one would doubt the road worthiness of someone who was on something like Benzodiazepine’s yet the minute cannabis is mentioned it is somehow different.

No one can condone driving whilst under the influence of any substance yet at the same time it would be nice if the laws of the land actually involved a sense of rational and science behind it.