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Reefer Madness: Driving High Doubles Likelihood of Fatal Crash

New research finds that high drivers are twice as likely to cause a fatal crash as sober drivers

February 9, 2012 RSS Feed Print

Driving with a doobie is now officially a bad idea: According to Canadian researchers, people who smoke marijuana within three hours of driving are twice as likely to cause a crash than someone who is sober.

The researchers, from Dalhousie University, examined and analyzed nine previous studies and determined that people who drove high are slightly more than twice as likely to be involved in a fatal crash. They are about 1.75 times as likely to cause a non-fatal collision.

"The impact of acute cannabis consumption on the risk of minor crashes remains unclear," according to the authors. "These results converge with those from experimental studies suggesting that cannabis impairs performance of the cognitive and motor tasks necessary for safe driving."

[Debate Club: Should federal authorities be able to close medical marijuana dispensaries?]

In 2006, more than 10 million people admitted to driving under the influence of illegal drugs; 30.5 million people admitted to driving under the influence of alcohol, according to the United States Department of Health and Human Services.

Marijuana legalization advocates say that although driving while high is more dangerous than driving while sober, it's less dangerous than driving while drunk. According to the CDC, about a third of all traffic-related deaths involve alcohol, while other drugs account for closer to 20 percent of all traffic deaths.

According to the Canadian researchers, drivers with a blood-alcohol content of .08 are about 2.7 times as likely to be involved in a car accident as a sober person.

[Half in U.S. Support Legalizing Marijuana]

A recent article written by NORML, an organization working to reform marijuana laws, concedes that driving high is more dangerous than driving sober, but says it is better than driving drunk.

"Although acute cannabis intoxication following inhalation has been shown to mildly impair psychomotor skills, this impairment is seldom severe or long lasting," author Paul Armentano writes. "Unlike subjects impaired by alcohol, individuals under the influence of cannabis tend to be aware of their impairment and try to compensate for it accordingly, either by driving more cautiously or by expressing an unwillingness to drive altogether."

jkoebler@usnews.com

Twitter: @jason_koebler

Tags:
driving,
marijuana

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The thing that I'm actually upset most by in this article is the fact that these people really think the American people are this stupid. I can't believe they sincerely wrote this drivel.

Helen of CA 3:32AM February 15, 2012

ADDITIONAL DATA:

* Relative risk of vehicle collision whilst under the 'acute' influence of cannabis is 1.92 whilst the relative risk of a similar vehicle accident with a blood alcohol content of 0.8 g/100 mL (the legal limit in many places) is 2.69.

* A 2002 review of seven separate studies involving 7,934 drivers reported, "Crash culpability studies have failed to demonstrate that drivers with cannabinoids in the blood are significantly more likely than drug-free drivers to be culpable in road crashes."

REFERENCE: G. Chesher and M. Longo. 2002. Cannabis and alcohol in motor vehicle accidents.

* A driver with a blood alcohol concentration (BAC) of 0.10 or greater is seven times more likely to be involved in a fatal motor vehicle crash than is a driver who has not consumed alcoholic beverages, and a driver with an alcohol concentration of 0.15 or greater is about 25 times more likely.

* In a 60 km/h zone the risk of involvement in a vehicle accident with casualties increases exponentially (doubles) with each 5 km/h increase in traveling speed.

* Talking on a Cell phone while driving Increases accident risk by a factor of 4.

* Texting while driving Increases accident risk by a factor of 23.

* Eating and drinking is a factor in more accidents than DUI, cell phone use or texting while driving.

* The smokers of cigarettes - even if they do not smoke while driving - have an increased accident risk of 1.5

* Smoking cigarettes while driving Increases accident risk by a factor of 2.

* Alcohol-related accidents are so prevalent, an estimated 40 percent of all persons in the United States will be involved in a traffic mishap blamed on alcohol at some point in their lives.

*** It is important to note that once marijuana is 'Legalized and Regulated', it will still be an offense to drive while impaired - DUI laws already apply to marijuana just like they do alcohol. The fact that being under the influence of a substance makes you a worse driver should have no bearing on its legality in general - otherwise we would be forced to hand the market in alcohol back to machine-gun tooting bootleggers.

malcolm kyle of DE 1:25PM February 10, 2012

ADDITIONAL DATA:

* Relative risk of vehicle collision whilst under the 'acute' influence of cannabis is 1.92 whilst the relative risk of a similar vehicle accident with a blood alcohol content of 0.8 g/100 mL (the legal limit in many places) is 2.69.

http://www.bmj.com/content/344/bmj.e536

* A 2002 review of seven separate studies involving 7,934 drivers reported, "Crash culpability studies have failed to demonstrate that drivers with cannabinoids in the blood are significantly more likely than drug-free drivers to be culpable in road crashes."

REFERENCE: G. Chesher and M. Longo. 2002. Cannabis and alcohol in motor vehicle accidents.

* A driver with a blood alcohol concentration (BAC) of 0.10 or greater is seven times more likely to be involved in a fatal motor vehicle crash than is a driver who has not consumed alcoholic beverages, and a driver with an alcohol concentration of 0.15 or greater is about 25 times more likely.

* In a 60 km/h zone the risk of involvement in a vehicle accident with casualties increases exponentially (doubles) with each 5 km/h increase in traveling speed.

http://www.infrastructure.gov.au/roads/safety/publications/1997/pdf/Speed_Risk_1.pdf

* Talking on a Cell phone while driving Increases accident risk by a factor of 4.

* Texting while driving Increases accident risk by a factor of 23.

* Eating and drinking is a factor in more accidents than DUI, cell phone use or texting while driving.

http://www.montlick.com/accident-blog/754-studies-show-eating-a-drinking-while-driving-may-be-a-greater-distraction-than-cell-phones

* The smokers of cigarettes - even if they do not smoke while driving - have an increased accident risk of 1.5

* Smoking cigarettes while driving Increases accident risk by a factor of 2.

http://www.ncbi.nlm.nih.gov/pubmed/2331646

* Alcohol-related accidents are so prevalent, an estimated 40 percent of all persons in the United States will be involved in a traffic mishap blamed on alcohol at some point in their lives.

http://alcoholism.about.com/cs/drive/a/aa070297.htm

*** It is important to note that once marijuana is 'Legalized and Regulated', it will still be an offense to drive while impaired - DUI laws already apply to marijuana just like they do alcohol. The fact that being under the influence of a substance makes you a worse driver should have no bearing on its legality in general - otherwise we would be forced to hand the market in alcohol back to machine-gun tooting bootleggers.

malcolm kyle of DE 1:22PM February 10, 2012

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