"Medical experts emphasize the need to reclassify marijuana as a Schedule II drug to facilitate rigorous scientific evaluation of the potential therapeutic benefits of cannabinoids and to determine the optimal dose and delivery route for conditions in which efficacy is established.2 This research could provide the basis for regulation by the Food and Drug Administration. Current roadblocks to conducting clinical trials, however, make this more rational route of approval unlikely and perpetuate the development of state laws that lack consistency or consensus on basic features of an evidence-based therapeutic program."
Hoffman, Diane E., and Weber, Ellen, "Medical Marijuana and the Law," New England Journal of Medicine (Boston, MA: Massachusetts Medical Society, April 22, 2010), Vol. 362, No. 16, p. 1457.