Despite Marijuana Legalization, Traffic Fatalities in Colorado Continue to Fall

Last month I
noted that marijuana legalization in Colorado does not seem to
have interfered with a downward trend in traffic fatalities, which
have been falling there since 2004. That period includes the
commercialization of medical marijuana (which started to take off
in 2009) and the legalization of recreational use (which took
effect at the end of 2012). My former
Reason colleague Radley Balko, who blogs about civil
liberties and criminal justice at The Washington Post,

points out that the downward trend in deadly crashes has
continued since the beginning of this year, when state-licensed pot
stores began serving recreational customers. According to data from
the Colorado Department of Transportation, the total number of
fatal crashes in the first seven months of this year was 258, down
from 263 during the same period last year. Here are the
monthly totals for 2014, compared to the
same months in 2013:

The trend in Colorado is broadly similar to the national trend
during the last decade. Balko notes that Colorado’s drop since 2004
looks more dramatic when compared to miles traveled, which have
continued to rise in Colorado while falling nationwide.

Does the continuing decline in fatal crashes mean that
legalization is
reducing fatalities by encouraging the substitution of
marijuana for alcohol (which has a more dramatic impact on driving
ability)? Not necessarily. In fact, from January through July the
total number of alcohol-related fatalities was 91, exactly the same
as the total for the first seven months of 2013:

Still, these numbers clearly are not consistent
with warnings
from prohibitionist groups such as Project SAM, which predicted
that legalizing marijuana would mean more blood on the highways.
Perhaps that grim prophecy will be realized one day, but so far it
looks wrong.