UCSF

Objectives

To determine whether state medical marijuana laws "send the wrong message," that is, have a local influence on the views of young people about the risks of using marijuana.

Methods

We performed multilevel, serial, cross-sectional analyses on 10 annual waves of the US National Survey on Drug Use and Health (2004-2013) nationally and for states with marijuana laws using individual- and state-level controls.

Results

Living in medical marijuana states was associated with more permissive views regarding marijuana across 5 different measures. However, these associations became non-statistically significant after we adjusted for state-level differences. By contrast, there was a consistent and significant national time trend toward more permissive attitudes, which was less pronounced among children of middle school age than it was among their older counterparts.

Conclusions

Passing medical marijuana laws does not seem to directly affect the views of young people in medical marijuana states. However, there is a national trend toward young people taking more permissive views about marijuana independent of any effects within states.