We've received mixed signals from the academic world when it comes to the effects of toking and driving.

One study even argued that those under the influence of cannabis were better drivers because, perhaps, they go slower and make more deliberate decisions.

This is important stuff right here in the pot shop capital of America. The British Medical Journal this week published what authors claim is the most definitive study of getting stoned behind the wheel yet. And it's not pretty. A BMJ statement:

Drivers who consume cannabis within three hours of driving are nearly twice as likely to cause a vehicle collision as those who are not under the influence of drugs or alcohol claims a paper published today on bmj.com.


The research combed over other studies of weed-related driving and eyeballed a total of nearly 50,000 people.

What's more, the researchers from Dalhousie University say their data is better because, for the first time, they were able to, er, weed out extraneous factors such as alcohol use:

Previous studies have failed to separate the effects of alcohol and other substances from the use of cannabis, resulting in a lack of agreement.

The researchers conclude …

… that the consumption of cannabis impairs motor tasks important to safe driving, increasing the chance of collisions and that future reviews should assess less severe collisions from a general driving population.

Interestingly, a Columbia University study late last year came to nearly the same conclusion.

Now you know. But we're sure this is not the end of the debate.

[@dennisjromero / djromero@laweekly.com / @LAWeeklyNews]

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