The use, sale, and possession of cannabis containing over 0.3% THC by dry weight in the United States, despite laws in many states permitting it under various circumstances, is illegal under federal law.[5] As a Schedule I drug under the federal Controlled Substances Act (CSA) of 1970, cannabis containing over 0.3% THC by dry weight (legal term marijuana) is considered to have "no accepted medical use" and a high potential for abuse and physical or psychological dependence.[6] Cannabis use is illegal for any reason, with the exception of FDA-approved research programs.[7] However, individual states have enacted legislation permitting exemptions for various uses, including medical, industrial, and recreational use.[8][9]
Cannabis for industrial uses (hemp) was made illegal to grow without a permit under the CSA because of its relation to cannabis as a drug, and any imported products must adhere to a zero tolerance policy.[10][11] The Agricultural Act of 2014 allows for universities and state-level departments of agriculture to cultivate cannabis for research into its industrial potential.[12] In December 2018, hemp was permitted to be grown in the U.S. under federal law after the Hemp Farming Act was included in the passed 2018 Farm Bill.[13]
As a psychoactive drug, cannabis continues to find extensive favor among recreational and medical users in the U.S.[14][15] As of 2023, twenty-four states, three U.S. territories, and the District of Columbia have legalized recreational use of cannabis. Thirty-eight states, four U.S. territories, and D.C. have legalized medical use of the drug. Multiple efforts to reschedule cannabis under the CSA have failed, and the U.S. Supreme Court has ruled in United States v. Oakland Cannabis Buyers' Cooperative (2001) and Gonzales v. Raich (2005) that the federal government has a right to regulate and criminalize cannabis, whether medical or recreational. As a result, cannabis dispensaries are licensed by each state;[16] these businesses sell cannabis products that have not been approved by the U.S. Food and Drug Administration,[17] nor are they legally registered with the federal government to sell controlled substances.[18] Although cannabis has not been approved, the FDA recognizes the potential benefits and has approved two drugs that contain components of marijuana.[19]
The ability of states to implement cannabis legalization policies was weakened after U.S. Attorney General Jeff Sessions rescinded the Cole Memorandum on January 4, 2018, and issued a new memo instructing U.S. attorneys to enforce federal law related to marijuana.[20] The Cole memo, issued by former Deputy Attorney General James Cole in 2013, urged federal prosecutors to refrain from targeting state-legal marijuana operations.[21] Regarding the medical use of cannabis, the Rohrabacher–Farr amendment still remains in effect to protect state-legal medical cannabis activities from enforcement of federal law.[22][23] On May 1, 2024, the Associated Press reported on federal plans to change marijuana to a Schedule III drug.[24]
^"State Industrial Hemp Statutes". National Conference of State Legislatures. April 18, 2018. Archived from the original on December 20, 2020. Retrieved July 5, 2018.
^"State Medical Marijuana Laws". National Conference of State Legislatures. June 27, 2018. Archived from the original on May 29, 2019. Retrieved July 5, 2018.