This week new research seems to contradict that analysis.
The study by Guohua Li of Columbia University's Mailman School of Public Health says that drivers who toke up before getting behind the wheel are twice as likely to crash as those who don't. According to a Mailman statement:
... Drivers who test positive for marijuana or who report using marijuana are more than twice as likely as other drivers to be involved in motor vehicle crashes.
And, for connoisseurs of L.A.'s fine, medical-grade bud, there's this warning:
The researchers also found evidence that crash risk increases with the concentration of marijuana-produced compounds in the urine and the frequency of self-reported marijuana use.
The research comes at a time when medical pot has been legalized in 16 states and Washington, D.C. and has become "the most commonly detected non-alcohol drug in drivers," according to Columbia.
Nearly one-third (28 percent) of drivers involved in fatal accidents tested positive for non-alcoholic drugs, of which marijuana is number one, according to the study, published in Epidemiologic Reviews.
Given the ongoing epidemic of drug-impaired driving and the increased permissibility and accessibility of marijuana for medical use in the U.S., it is urgent that we better understand the role of marijuana in causing car accidents.
In California cops have a hard time proving you were under the influence of marijuana at the time you were behind the wheel because elements of pot remain in your system long after your high has warn off.
That means you might have had your medicine in recent days, but it will be hard to prove in court that your medicine was in effect when you were behind the wheel.
Still, you could get charged with driving in possession of marijuana if you have weed on you and are stopped by police.
And there's that whole issue raised here -- of possibly dying and all.
So don't get high on your own supply ... before you drive.