Cannabis Prohibition – When, Why, And How?

Cannabis first became illegal in the UK, and most of the rest of the world, on 28th September 1928 when the 1925 Dangerous Drugs Act came into force. There were no British domestic reasons, no lobbying for or against prohibition, and no Parliamentary debates.

The Act controlling ‘Indian Hemp and all resins and preparations based thereon’ had been passed after Britain signed the 1925 Geneva International Convention on Narcotics Control, organised by the League of Nations. Asked what it was all about on a slow day in Parliament, a junior Home Office Minister explained that the Convention could not be ratified without an ‘important but small’ law being passed. ‘What it does is include coca leaves under a former Act. They are the real basis of cocaine – we place them in the same category as raw opium.’ Cannabis itself was ever mentioned aloud.

How Did Cannabis Became Illegal In The US

Recreational cannabis use was also relatively popular from around 1850 onwards, with oriental-style hashish bars to be found in most major cities in the US. The major restrictions on cannabis came to be enforced through poison laws such as the Pure Food and Drug Act, passed by Congress in 1906. This law required certain drugs, including cannabis, to be accurately appropriately labeled.From there on out, individual states began to pass their own laws regarding specific labeling of drugs such as cannabis. For example, further regulations regulating the sale of cannabis and cannabis-derived products followed in Massachusetts in 1911, and in New York and Maine in 1914.

  • In 1925 the US officially supported the the regulation of Indian Hemp (essentially THC-rich cannabis) at the International Opium Convention. The convention restricted the exportation of Indian hemp and any derivative products (such as hashish) to countries that had already banned the substance.
  • By 1930, the US formed the Federal Bureau of Narcotics as a push to outlaw and control recreational drugs. The bureau was lead by Harry J. Anslinger who, as we’ll see, is often crowned the father of cannabis prohibition in the US.
  • In 1932, the US passed the Uniform State Narcotic Act, which basically called for all states to unite in their front against the traffic of narcotic drugs and manage trafficking under uniform laws. By the mid 30s, all US states had enforced some kind of regulation on cannabis.
  • The possession or transfer of marijuana for recreational uses officially became illegal across the US under federal law in 1937 under the Marijuana Tax Act.
  • In 1970, the Tax Act was replaced by the Controlled Substances Act, which officially listed controlled under 5 different schedules based on their danger and risk of addiction, with Schedule I substances deemed the most dangerous and addictive. Cannabis was listed as a Schedule I drug.

Schedule I substances are described to possess a high potential for addiction, no currently accepted medical uses, and completely unsafe.

Why Was Cannabis Criminalized?

This is where theories get very interesting and complex. Harry J. Anslinger, the head of the US Federal Bureau of Narcotics, is often noted as one of the pivotal members in cannabis prohibition in the US. Anslinger held his position as commissioner of the bureau for 32 years (until 1962) and also served U.S. Representative to the United Nations Narcotics Commission for 2 years. Prior to his role at the bureau, Anslinger also served as the head of Department of Prohibition in Washington, D.C. According to Johann Hari, author of the book “Chasing The Scream: The First and Last Days of the War on Drugs,” Anslinger began his focus on cannabis after alcohol prohibition ended in 1933. Up until this point, Anslinger allegedly said he saw no problem with cannabis, mainly as it didn’t hurt anyone nor make anyone violent.

However, Anslinger quickly changed his mind, noticing that (according to Hari) he was in charge of a huge department with nothing to do. So, Anslinger quickly came to warn people about the effects of cannabis; first it would throw you into a delirious rage; then you’d suffer from erotic dreams/hallucinations, before finally reaching the inevitable endpoint: insanity. He was quite known for his ridiculous and racist quotes on cannabis and cannabis users. Anslinger’s go-to case to demonstrate the power of the “devil’s weed” was that of Victor Licata, a boy from Florida who hacked his family to death with an axe. This case, combined with a statement from 1 doctor that cannabis was dangerous (out of 30 Anslinger contacted, 29 who apparently answered “no”), would go on to be Anslinger’s fuel to instill fear in the hearts of all Americans about the power of “the demon weed.”

In 1936, the bureau noticed an increase in the use of marijuana. This increase continued growing by 1937. At This point, Anslinger launched a campaign against cannabis (Reefer Madness!), leveraging media mogul William Randolph Hearst’s newspaper empire to demonize the cannabis plant. By 1937, cannabis officially became an illegal substance across the US under the Marijuana Tax Act.

War on drugs motivated by racial issues

In an article on, Dr. Malik Burnett and Amanda Reiman propose an interesting argument on how Mexican immigration affected the move to marijuana prohibition in the early 1900s.

While we won’t explore Burnett and Reiman’s argument in full detail, we’ll summarize it here because we think it raises a very interesting point.

The Mexican Revolution was a violent struggle that took place from roughly 1910-1920 and radically changed Mexican culture and government. The revolution lead to a large influx of immigrants to the US, especially into states like Texas and Louisiana, who brought with them new customs and cultures.
The book “Brave New Weed: Adventures into the Uncharted World of Cannabis” is a look into the American war on weed by author Joe Dolce. Dolce looks at the war on drugs as having been motivated by racial issues. Every household in America knew cannabis very well, as it was an ingredient in almost all commonly used medicines and tinctures of the 1900’s.

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At the same time, the Mexican Revolution brought many immigrants from Mexico to states such as Texas and Louisiana. The immigrants brought with them their customs, language and culture. They often used cannabis to relax and as a medicine. Mexican immigrants referred to the plant as “marihuana”. When the media at the time started spreading unfounded propaganda, marihuana became synonymous with dark colored men becoming violent and soliciting sex with white women. Americans didn’t realize they all had extracts of the same plant in their medicine chest.

Cannabis Prohibition Around The World

Cannabis laws vary from country to country. However, cannabis became illegal in most nations in 1925 after the International Opium Convention, a follow up to the first convention signed in 1912 at the The Hague in The Netherlands. The convention of 1912 essentially served as the first international drug control treaty and was particularly concerned with the growing trade and use of opium. It was signed by Germany, the United States, China, France, the United Kingdom, Italy, Japan, the Netherlands, Persia, Portugal, Russia, and Siam. A revised International Opium Convention was then held in 1925 in Geneva, Switzerland. At this convention, Egypt, China, and The US suggested a prohibition on hashish be added to the text of the treaty, which was previously mainly concerned with cocaine and opium.

A sub-committee suggested expanding the text to prohibit the production, sale, and trade of charas hashish, and various other products derived from cannabis, while restricting the use of Indian hemp strictly for scientific and medical purposes. India and a few other countries, however, objected to this, arguing that due to various social and religious customs as well as the prevalence of wild cannabis would make it difficult to enforce these restrictions. Hence, this text never made it into the final treaty, However, the exportation of Indian hemp was banned to any country where it has been illegalized. Any countries wishing to import Indian hemp had to demonstrate that its use was strictly for medical or scientific purposes. Meanwhile, all nations were expected to do their best to prevent the international trade of indian hemp and products such as hashish.

In 1961, the Convention was effectively replaced by the Single Convention on Narcotic Drugs, which became the first international treaty to officially prohibit cannabis. Held and signed in New York City, this treaty broadened the effects of those before it to control and restrict new opioid drugs and broaden the scope on cannabis. The Convention gave the Commission on Narcotic Drugs and the World Health Organization the power to add, remove, and transfer drugs between four different schedules established by the treaty.

Meanwhile, the International Narcotics Control Board was put in charge of administering controls on drug production, international trade, and dispensation, and the United Nations Office on Drugs and Crime (UNODC) was delegated to work with individuals countries and their authorities to ensure compliance with the convention. So, there you have it; a detailed look at when, how and why cannabis became illegal in the US and around the world.

Some of the Info Provided By: Wikipedia

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