As part of the “War on Drugs,” the Controlled Substances Act of 1970, signed into law by President Richard Nixon, repealed the Marijuana Tax Act and listed marijuana as a Schedule I drug—along with heroin, LSD and ecstasy—with no medical uses and a high potential for abuse.
In 1972, a report from the National Commission on Marijuana and Drug Abuse (also known as the Shafer Commission) released a report titled “Marijuana: A Signal of Misunderstanding.” The report recommended “partial prohibition” and lower penalties for possession of small amounts of marijuana. Nixon and other government officials, however, ignored the report’s findings.
California, in the Compassionate Use Act of 1996, became the first state to legalize marijuana for medicinal use by people with severe or chronic illnesses. Washington, D.C., 29 states and the U.S. territories of Guam and Puerto Rico allow the use of cannabis for limited medical purposes.
As of January 2018, nine states and Washington, D.C., have legalized marijuana for recreational use. Colorado and Washington became the first states to do so in 2012. Adults also can light up without a doctor’s prescription in Alaska, California, Maine, Massachusetts, Nevada, Vermont and Oregon.
Cannabis is still illegal under U.S. federal law, however, and the evolving legal status of marijuana is a subject of ongoing controversy in the United States and around the world.