Medical Marijuana: The Supremacy Clause, Federalism, and the Interplay Between State and Federal Laws [March 6, 2012] [open pdf - 269KB]
"As part of a larger scheme to regulate drugs and other controlled substances, federal law prohibits the cultivation, distribution, and possession of marijuana. No exception is made for marijuana used in the course of a recommended medical treatment. Indeed, by categorizing marijuana as a Schedule I drug under the Controlled Substances Act (CSA), the federal government has concluded that marijuana has 'no currently accepted medical use in treatment in the United States.' Yet 16 states and the District of Columbia have decriminalized medical marijuana by enacting exceptions to their state drug laws that permit individuals to grow, possess, or use marijuana for medicinal purposes. In contrast to the complete federal prohibition, these 17 jurisdictions see medicinal value in marijuana and permit the drug's use under certain circumstances. [...] This report will review the federal government's constitutional authority to enact the federal criminal prohibition on marijuana; highlight certain principles of federalism that prevent the federal government from mandating that states participate in enforcing the federal prohibition; consider unresolved questions relating to the extent to which state authorization and regulation of medical marijuana are preempted by federal law; and assess what obligations, if any, the U.S. Department of Justice (DOJ) has to investigate and prosecute violations of the federal prohibition on marijuana."
CRS Report for Congress, R42398