DO MEDICAL-MARIJUANA LAWS REDUCE HIGHWAY DEATHS?

Medical-marijuana laws reduce traffic deaths, according to a new
study, probably because people in states with such laws partly
substitute marijuana for alcohol - and alcohol is more deadly when
combined with driving.

Fifteen states plus the District of Columbia have passed
medical-marijuana laws since 1996. Examining National Highway Traffic
Safety Administration data before and after the passage of those laws,
the researchers found a nearly 9% decrease in overall traffic
fatalities. (The calculations also took account of trends in
neighboring states.) That decline was caused entirely, or nearly so,
by a drop in alcohol related traffic deaths.

In states that have legalized medical marijuana, the researchers found
evidence of an increase in marijuana consumption-beyond prescription
uses - among people over 18 (but not under 18).* According to their
analysis of data collected by the Centers of Disease Control and the
states, those states have also seen a slight drop in alcohol
consumption. Taken as a whole, the data suggest that marijuana is
being used as a partial replacement for drinking, and not only a
supplement to drinking.

Like alcohol, marijuana hinders physical coordination. People who are
high, however, tend to be more aware of their intoxication, and less
aggressive and reckless, than people who are drunk, the researchers
said. Another factor in the fatality drop may be that people consume
marijuana in private, rather than in bars (or sports stadiums) they
drive home from.

Source: "Medical Marijuana Laws, Traffic Fatalities, and Alcohol
Consumption," D. Mark Anderson and Daniel I. Rees, Institute for the
Study of Labor working paper (November)

*That medical-marijuana laws lead to more marijuana use among adults
was the general trend, but it wasn't universal. Montana, where nearly
3% of the population has a marijuana prescription (!), and Rhode
Island, where only some 3,000 people do, both saw increases in pot
consumption. Vermont, however, with a medical-marijuana patient roster
measured in the hundreds, did not see an increase in pot consumption.