Cannabis/Marijuana State Policies and Suicide Interests in the United States

The use of cannabis is prohibited by the federal government in the U.S. and different states in the U.S. have different policies on cannabis possession and sales. The different policies are expected to affect the access and use of cannabis differently. The possible effect of cannabis policies and interests in cannabis use on suicide ideation is investigated in this paper. The suicide – cannabis/marijuana policy relationship has only been investigated at the micro or individual level of analysis; the novelty of this paper lies in the use of state level time series data to test the relationship as opposed to using individual data. Another novel aspect of this paper lies in its use of state level google trends data to measure interests in cannabis and marijuana at the state level. Google trends data measures relative search volume ranging from 0 -100 for specific google search queries. The relative search volume for a variety of variables which measure the internet based interest in the variables have been shown to be strongly correlated with the actual values of the variables (Choi and Hal, 2012). A counterfactual approach using fixed effects regression analysis is used to investigate the relationship between the interest in suicide and cannabis/marijuana state level policies.  Accounting for a variety of confounding factors, the results show that states where there is no clear legal or illegal cannabis/marijuana policy have individuals with higher interest in suicide compared to states where cannabis/marijuana is legal or illegal by law. No significant difference is found among states where cannabis/marijuana is legal and states where cannabis/marijuana is illegal.