Marijuana playing larger role in fatal crashes

But, hey, we're getting tax revenue in exchange for all the extra fatal accidents:


As more states are poised to legalize medicinal marijuana, it's looking like dope is playing a larger role as a cause of fatal traffic accidents.

Columbia University researchers performing a toxicology examination of nearly 24,000 driving fatalities concluded that marijuana contributed to 12% of traffic deaths in 2010, tripled from a decade earlier.

NHTSA studies have found drugged driving to be particularly prevalent among younger motorists. One in eight high school seniors responding to a 2010 survey admitted to driving after smoking marijuana. Nearly a quarter of drivers killed in drug-related car crashes were younger than 25. Likewise, nearly half of fatally injured drivers who tested positive for marijuana were younger than 25.

A National Highway Traffic Safety Administration study found that 4% of drivers were high during the day and more than 6% at night, and that nighttime figure more than doubled on weekends.

Colorado has seen a spike in driving fatalities in which marijuana alone was involved, according to Insurance.com. The trend started in 2009 — the year medical marijuana dispensaries were effectively legalized at the state level.

http://www.usatoday.com/story/money/cars/2014/06/09/marijuana-accidents/10219119/

 

Its a victimless crime?

 

Call me when alcohol is banned.

 

Colorado fatal accidents by year
2005 - 554
2006 - 485
2007 - 508
2008 - 473
2009 - 437
2010 - 409
2011 - 407
2012 - 433

 

So?

 

So if marijuana use since 2009 is causing more fatal crashes, we'd expect to see the number of fatal crashes in Colorado go up, not go down. It's obviously a fairly basic look at things, but there's no evidence that increased marijuana use since 2009 is leading to more fatal crashes. (I don't have death per 100 million vehicle miles traveled numbers for pre-2009 so I can't compare using that. Maybe people were just driving less. But since 2009, Colorado has ranked below average as a state in number of deaths per 100 million vehicle miles traveled.)

 

Traffic deaths involving marijuana are up.

It matters little if overall traffic deaths are down. The numbers would be down more if not for marijuana.

 

Colorado fatalities per 100 million miles traveled by year, 1997-2011
1.74 1.84 1.71 1.62 1.60 1.54 1.63 1.73 1.71 1.48 1.45 1.26 1.10 1.14 1.15 1.01 0.96 0.96

No jump since 2009 (2009 is the 1.01 number).
Part of a nation-wide trend in reduced fatalities since 1997.
Average state has seen fatalities drop 36% per 100 miles traveled since 1997. Colorado at 45% drop.

 

Maybe. Maybe not. That's my point.
I bet traffic deaths while one or more of the cars involved were listening to Katie Perry are up, starting in roughly 2009, too.

 

What do you think is in dispute:

 

Mostly I'm pissed off at the lazy use of statistics in the USA Today article. I'm half-heatedly disputing the correlation. It might be there, but the Colorado fatality numbers don't show it at a glance.
Anything that's been increasing in usage will have increasing number of people killed right after doing it, since it's trend line is going up.
Hence the Katie Perry example - Katie Perry became big in the late 2000s, as far as I know (I'm not that musically hip). As a result, more people were listening to her right before crashing their car. that doesn't mean Perry caused the crash.
I would bet money that since 2009, we've seen a sharp increase in the number of drivers in fatal car crashes who'd had a gluten-free meal that day.
These are the same as the Colorado number the author quoted.
Without more statistical context, it's just not a damning indictment of marijuana use.
That damning indictment might be out there, but it's not in this article.


(The article from nbcnews also has this fun tidbit:
A separate study — also based on FARS data — found that in states where medical marijuana was approved, traffic fatalities decrease by as much as 11 percent during the first year after legalization. Written by researchers at the University of Colorado, Oregon and Montana State University, the paper was published in 2013 in the Journal of Law & Economics.)

 

in which marijuana alone was involved !!

Learn to read, please. My gout is flaring up again