we conclude that medical marijuana legalization does not appear to lead to changes in suicide rates. Instead, it appears that medical marijuana legalization is correlated with changes in other factors that contribute to suicide risk, such as the demographic makeup of states and tobacco control policies. Medical marijuana legalization also corresponded with changes in age of state populations and per-capita mental health spending. These variables were not associated with suicide risk in our study, but may be relevant to other public health outcomes. Thus, extant studies of medical marijuana policy and public health outcomes that have not accounted for these differences should be interpreted cautiously, and future studies should take these factors into account.
