
Traffic fatalities linked to marijuana are up sharply in Colorado - mcone
http://www.denverpost.com/2017/08/25/colorado-marijuana-traffic-fatalities/
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danielvf
Obviously if the percentage of drivers testing positive for marijuana went up,
but the number of fatal accidents stayed the same, then we would just be
seeing a demographic shift, but no possible causal link.

The first half of the article doesn't address this, which left me wondering
how real the effect was. However, near the end: "The 2013-16 period saw a 40
percent increase in the number of all drivers involved in fatal crashes in
Colorado, from 627 to 880"

That kind of move is at least worthy of further scrutiny.

~~~
15155
> The 2013-16 period saw a 40 percent increase in the number of all drivers
> involved in fatal crashes in Colorado, from 627 to 880

Is this number controlling for population growth? The article wasn't clear: CO
has had an overwhelming influx of new residents since 2013.

~~~
danielvf
Looks like Colorado grew by about 5% from 2013 to 2016. That would reduce the
size of the effect, but it's still huge.

Also important is that 2013 was a national low in fatal traffic accidents,
rates have been higher on average since.

Still, the Colorado increase is outsized.

~~~
lawnchair_larry
That's still quite a leap, considering the variability of traffic accident
statistics. For example a good winter storm can cause hundreds of (non-fatal)
accidents on its own, and storm patterns are highly inconsistent from year to
year. I mean, imagine what kind of "scary link" you could find by looking at
any changes made in the state of Louisiana in 2005 and forgetting to account
for Hurricane Katrina.

Has there been an increase in tourism? Specifically, folks from neighboring
states coming to buy marijuana?

Does it correlate with an increasing snapchat-using demographic reaching
driving age? Another CDOT official believes distracted driving is causing the
surge:

[http://www.denverpost.com/2017/01/31/colorado-roadway-
fatali...](http://www.denverpost.com/2017/01/31/colorado-roadway-fatalities-
surge-2016/)

(Yet the article seems to spend more time talking about a decrease in seatbelt
usage, which would also boost the fatality stat)

What do other states that legalized at the same time report?

Washington says despite the national average going up, crashes there went
_down_. They credit themselves for being strict on distracted driving.

[http://www.seattletimes.com/seattle-
news/transportation/traf...](http://www.seattletimes.com/seattle-
news/transportation/traffic-deaths-up-nationwide-down-slightly-in-washington-
state/)

Junk article really, most likely to be abused as a political tool by people
who don't understand stats.

