Research indicates that traffic fatalities are on the decline in states like Michigan, where medical marijuana is legal.

Economists Daniel Rees of the University of Colorado Denver and Mark Anderson of Montana State University conducted the study, and found that fatalities are down an average of 9% in the thirteen states that have made doctor-prescribed pot acceptable.

The reasons?

Researchers have two theories:  Drunk drivers don't realize how impaired they are, they drive faster, and take more risks. Drivers under the influence of marijuana tend to drive slower, and take fewer risks.

They also theorize that people under the influence of pot don't go out as much.

The Beer Institute indicates that beer sales have dropped in states where medical marijuana is legal.

[ABC]