Cannabis Critics Assail Study Linking Drop in Traffic Fatalities to Medical Marijuana Laws

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Last week, an independent research institute in Germany released a report by two university economics professors showing that deaths from traffic accidents have actually declined 9% in states that passed medical marijuana regulations.

As we said in our article on the study, it was only a matter of time before critics emerged. And emerge they have.

Arthur Dean, the chairman and chief executive officer of the Community Anti-Drug Coalitions of America, wrote in a blog post that the study is fatally flawed, saying researchers didn’t take into account the fact that traffic deaths had already been decreasing. He also takes issue with the study’s conclusion that medical pot laws lead people to drink less alcohol – therefore resulting in fewer accidents involving drunk drivers – by calling it a “spurious and coincidental relationship.”

“Just because A happened when B happened does not mean that A caused B,” Dean wrote. His other concerns center on the methodology of the study – some of the research only involves three MMJ states with miniscule patient numbers at the time – and a failure to account for the effects of driving while stoned.

Kevin A. Sabet, a former senior adviser to the director of the White House Office of National Drug Control Policy, raises similar criticisms in a column published yesterday in the Huffington Post, saying that drawing firm conclusions from the study is “disingenuous and dangerous.”

Aside from the methodology and the lack of context, Sabet takes issue with the fact that the report is a discussion paper, “not a peer-reviewed study in a scientific journal.” He also faults the mainstream media for writing about it as if it is fact and argues that researchers ignored other data that run counter to their conclusions.

This is par for the course when it comes to studies about medical marijuana and the industry in general. No matter the results, one side or the other debates the credibility of the study, as happened recently with another controversial study on the effects of MMJ on crime in Los Angeles.