By Joanna R. Lampe

State marijuana laws have changed significantly in recent years, and federal law appears poised to change in the coming months. At the state level, many states have enacted laws authorizing the use of marijuana for medical purposes. A smaller but growing number of states have also amended their laws to legalize or decriminalize marijuana use. At the federal level, in April 2024, news outlets reported that the Drug Enforcement Administration (DEA) planned to change the status of marijuana under the Controlled Substances Act (CSA) by moving it from Schedule I to the less restrictive Schedule III. Under current law, many cannabis-related activities that comply with state law may nonetheless violate the federal CSA. Moving marijuana to Schedule III would not bring state-legal marijuana markets into compliance with federal law. In light of recent and proposed changes to state and federal marijuana regulation, this Sidebar provides an overview of the divergence between federal and state marijuana law. It then briefly discusses the legal consequences of the divergence and outlines certain related considerations for Congress.

Washington, DC: Congressional Research Service, 2025. 5p.