Observations of the role of science in the United States medical cannabis state policies: Lessons learnt

Background Clinical trials have shown cannabis to be effective in the treatment of some medical conditions and there is mounting public and political pressure to enact laws enabling the use of cannabis for medicinal purposes. To date, 28 United States (U.S.) states and the District of Columbia have enacted medical cannabis laws. This study sought to identify the main issues pertaining to the development of medical cannabis laws in the U.S, including the role of scientific evidence. Methods Data were collected from three groups of participants: government officials, lobbyists and medical professionals involved in the medical cannabis debate in five selected states in the U.S.; researchers from the same five states conducting funded research in the alcohol and other drugs field; and members of the International Society for the Study of Drug Policy. The data were analysed using thematic analysis. Results Six major themes emerged in relation to the factors influencing policy: scientific evidence plays a limited role in the development of policy; the available research is limited and mixed; there is a need for clearer communication and active dissemination of evidence to policy makers; researchers need to consider what research is likely to impact on policy; scientific evidence is not a major factor in policy development; and there is a need to consider evidence within a political context. Conclusion Researchers need to be aware of the political context in which medical cannabis laws are or are not enacted and consider ways in which research findings can achieve a higher profile within this context