The use, possession, sale, cultivation, and transportation of cannabis is illegal under federal law in the United States. However, the federal government has articulated that if a state passes a law to decriminalize cannabis for recreational or medical use, they can do so, under the condition that a regulation system for cannabis is in place. Cannabis is listed as a Schedule I substance under the Controlled Substances Act of 1970, the highest classification under the legislation. Part of the reason marijuana remains illegal at the federal level is because it is classified as a Schedule I drug. A Schedule I drug, as defined by the Drug Enforcement Administration, is a substance that has a high potential of being abused by its users and has no acceptable medical uses.
Individual state laws do not always conform to the federal standard. State-level proposals for the rescheduling of cannabis have met with mixed success. As of November 9, 2016, the use of both recreational and medicinal marijuana has been legalized in the states of Alaska, California, Colorado, Maine, Massachusetts, Nevada, Oregon, and Washington. The District of Columbia has fully legalized recreational and medical marijuana, but recreational commercial sale is currently blocked by Congress. Twelve states have both medical marijuana and decriminalization laws (three of them being CBD only). Twelve states, Guam, and Puerto Rico have legalized psychoactive medical marijuana, while another twelve have only legalized non-psychoactive medical marijuana. One state and the U.S. Virgin Islands have only decriminalized possession laws. In the remaining five states and two inhabited territories, marijuana possession and sales are illegal and prohibited entirely.