Cannabis has likely been with humans as long as we’ve been growing crops, about 10,000 years.
The plant has always been a big part of our lives and culture because of its many uses: its seeds can be eaten, its fibers turned into materials, and its buds used for medicine, spiritual practices, and recreation. Because of its usefulness, humans spread cannabis seeds all across the globe.
So how did cannabis become illegal in the United States and throughout much of the world? And if it’s been useful to humans for millennia, why are more than 500,000 people in the US punished for growing and possessing the plant every year?
Cannabis arrived in the Americas a few hundred years ago ( relatively late compared to the rest of the world), and in that time, it went from cash crop to doctor-recommended cure-all to demon weed.
Learn how cannabis came to America, how it was prohibited, and how the country is starting to embrace it once again.
How weed came to the Americas
From its origins in Central Asia, cannabis eventually made its way to present day India, East Africa, and the Middle East through human migration. Arabic traders are thought to have spread the plant throughout North Africa and into Spain, which was part of various Arab or Berber states from the 8th-15th centuries. Eventually, Christian European kingdoms conquered Spain, and the Spanish Catholic powers first invaded the Americas beginning in 1492.
Hemp is believed to have been brought to present day Mexico by Pedro Cuadrado, a conquistador in Cortes’ army. Cuadrado and a friend started a successful business growing hemp. However, in 1550, a Spanish governor restricted production because the locals were getting high with the plant rather than using it for rope and textiles.
Hemp in the United States
Hemp was also a popular source of textiles and other materials in what would become the United States. In 1611, King James I of England issued a royal decree that colonists of the colony of Jamestown, Virginia grow hemp. The valuable crop could be used to make rope, sails, clothes, textiles, and other materials, and was sometimes more valuable than money.
In 1611, King James I of England decreed that all colonists of the 13 colonies grow hemp.
In 1839, Irish doctor William O’Shaughnessy brought cannabis as a medicine to the attention of Western medical practitioners when he published On the preparations of the Indian hemp, or gunjah after working in India and experimenting with the plant there.
Cannabis tinctures and other products then became popular in Europe and the US. Countless medicines containing cannabis claimed to cure various ailments, and the plant became so popular that more than 100 studies were conducted on it in the last half of the 19th century.
The beginnings of prohibition
After the Mexican Revolution (1910-1920), many Mexicans migrated to the US. Cannabis was more normalized in Mexican culture. White politicians opposing immigration vilified Mexican Americans and cannabis, referring to the plant as “locoweed” and by its Spanish name “marihuana,” to negatively associate it with Mexican immigrants and Mexican Americans.
In 1913, California became the first state to outlaw the plant, amending its Poison Act to include cannabis. The state was a pioneer in anti-drug laws. In 1875, San Francisco passed an ordinance against opium dens. And by 1907, the state had outlawed the sale of opium, morphine, and cocaine without a doctor’s prescription.
Utah, Texas, and New Mexico soon followed suit in prohibiting the plant, and by the early 1930s, 29 states had outlawed cannabis.
In 1930, the Federal Bureau of Narcotics was created and Harry J. Anslinger was appointed as its first commissioner. He worked for the government during alcohol prohibition and was determined to apply his lessons learned from that time toward cannabis. Anslinger would lead the charge to demonize and prohibit the plant in the US over the next 30 years.
The Marihuana Tax Act of 1937
Years of yellow journalism and scare-mongering in the newspapers owned by tycoon William Randolph Hearst helped create a sense of fear around cannabis in the 1930s in America. The plant was depicted as a dangerous drug that caused Black Americans, Mexican immigrants, and members of the lower classes to commit crimes.
The Marihuana Tax Act of 1937 levied a tax against cannabis so punitive that no one could pay it.
Fear of the plant reached the mainstream with the propaganda film Reefer Madness, released in 1936. The film was meant to warn parents of the supposed dangers of cannabis use, portraying various horrible incidents that occur to a group of teenagers all because they smoke some pot. Today, the film is a cult classic and an example of the ridiculous exaggerations of the effects of cannabis many people believed decades ago.
Congress saw how states were prohibiting cannabis and responded with the Marihuana Tax Act in 1937. At the time, the US federal government lacked the power to ban cannabis, so it levied a tax so punitive that no one could pay it. Drafted by Anslinger, the act imposed a heavy tax against anyone using the plant. Failure to comply meant a fine of up to $2,000 and up to five years in jail. The first marijuana arrest under the new federal law was a small-time weed dealer in Denver, Colorado.
More than a decade later, in 1951, Louisiana congressman Hale Boggs convinced Congress to pass the Boggs Act, which established mandatory sentences for drug offenses for the first time in the US. Originally it was only intended for hard drugs, but Anslinger testified and pushed to add cannabis to the list.
The Controlled Substances Act
In 1965, Timothy Leary (who would go on to be an advocate for psychedelics) was arrested for possession of cannabis while crossing the border from Mexico into Texas. Leary argued that the Marihuana Tax Act required him to self-incriminate—registering for the act showed intent to possess marijuana, which would violate the fifth amendment. The US Supreme Court agreed with him in 1969 and struck down the Marihuana Tax Act.
However, with the loss of the Tax Act, President Richard Nixon passed the Controlled Substances Act in 1970, setting up a framework for the federal regulation and criminalization of drugs. The Controlled Substances Act created five categories of drugs and classified cannabis under Schedule I—drugs considered dangerous with no medical use and a high potential for abuse, such as heroin and cocaine.
The Controlled Substances Act of 1970 set up a framework for the criminalization of drugs, placing cannabis in the most restrictive category.
Nixon appointed former Pennsylvania Republican governor Raymond Shafer as the head of the National Commission on Marihuana and Drug Abuse—later called “The Shafer Commission”—to review all research and literature on cannabis to correctly classify it in the Controlled Substances Act.
Shafer’s 1972 report debunked damaging myths about marijuana, found that the plant did not threaten society, and recommended decriminalizing the plant. Nixon ignored the report, and the plant stayed on Schedule I, where it remains today.
Despite the creation of the Controlled Substances Act, some individual states still began eliminating penalties and decriminalizing cannabis by themselves. By 1977, a fine—not imprisonment—was the only possible penalty in Alaska, California, Colorado, Maine, Minnesota, Ohio, and Oregon for possession of fewer than 100 grams (3.5 oz). Other states soon followed suit.
The War on Drugs
“The War on Drugs” was coined by the media after a 1971 press conference in which President Nixon declared drug abuse America’s “public enemy number one.”
Just before the Shafer report came out, in 1971, President Nixon held a press conference in which he declared drug abuse as America’s “public enemy number one.” He increased penalties and incarceration for drug offenders and increased law enforcement presence in the country, particularly with the creation of the DEA (Drug Enforcement Administration) in 1973. The media started referring to these policies as the “War on Drugs.”
Many years later, John Ehrlichman, Nixon’s domestic policy advisor, commented on the Nixon administration’s purpose with the War on Drugs:
“We knew we couldn’t make it illegal to be either against the [Vietnam] War or Black [Americans], but by getting the public to associate the hippies with marijuana, and Blacks with heroin, and then criminalizing both heavily, we could disrupt those communities. We could arrest their leaders, raid their homes, break up their meetings, and vilify them night after night on the evening news. Did we know we were lying about the drugs? Of course we did.”
President Ronald Reagan carried the torch, passing the Comprehensive Crime Control Act of 1984, a revision of the criminal code which increased federal penalties of cannabis possession, cultivation, and distribution. It also abolished parole for federal prisoners and established civil asset forfeiture.
Under Reagan, the Anti-Drug Abuse Act of 1986 enhanced federal mandatory minimum sentences for drugs, including marijuana possession. Systemic racism reared its ugly head again with significant sentencing disparities between crack, which was more associated with people of color, and cocaine, which was more associated with white people. Possession of five grams of crack carried the same penalty as 500 grams of cocaine: a minimum mandatory sentence of five years in federal prison.
The number of people imprisoned for nonviolent drug offenses in the US skyrocketed, from 50,000 in 1980 to over 400,000 in 1997.
The racial disparities continue to this day: Black and white Americans both consume cannabis at the same rate, yet Black Americans are nearly four times as likely to be arrested for marijuana possession. In some states, it’s even higher.
In 2010, more than 50% of drug arrests were for marijuana possession, and it is estimated that states waste more than $3.5 billion a year enforcing marijuana laws.
The medical and recreational cannabis eras
Hope began to emerge for the plant in the last decade of the 20th century, when marijuana legalization first took shape under medical defenses to possession and cultivation.
In 1996, California voters led the way with Proposition 215. Stricken by the AIDS crisis, San Francisco activists “Brownie Mary” Rathbun and San Francisco Cannabis Buyer’s Club owner Dennis Peron disobeyed pot laws to give cannabis to the sick and dying. They showed that cannabis could be an affordable, safe substance used to combat nausea, vomiting, wasting, spasticity, and many other AIDS- and cancer-related conditions.
In 1996, California became the first state to vote in medical marijuana.
In 1998, Alaska, Oregon, and Washington became the second, third, and fourth states to legalize medical marijuana, and Maine, Hawaii, Colorado, and Nevada followed soon after. Today over 40 US states and territories have some form of medical marijuana law.
In 2012, Colorado and Washington became the first US states to legalize cannabis recreationally for adults 21 and up. Medical marijuana laws and regulations offered a framework for recreational marijuana laws, and Colorado’s expanded its already extensive medical regulations to include adult-use rules. By contrast, Washington’s medical marijuana system lacked strong regulation, and adult use ushered better regulation of both programs into the state.
Oregon and Alaska followed with adult-use legalization in 2014. In 2016, California, Maine, Massachusetts, and Nevada legalized, then Michigan and Vermont in 2018, and Illinois in 2019. As of 2020, 68% of Americans believe cannabis should be made legal.
However, despite 18 US states and two US territories having legal, adult-use cannabis laws and 41 states and territories having legal medical marijuana laws, cannabis is still illegal at the federal level in the US.
Attitudes are shifting in the US and abroad. Still, it is imperative to build a framework inclusive of the BIPOC community, and that undoes the harms of prohibition and the War on Drugs, which have affected that community so much. Much work will still need to be done even after the plant is federally legalized.
For more information on current legalization in the US, check out Leafly’s guide to marijuana legalization.
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