EducationWhy was cannabis banned in the UK?

Why was cannabis banned in the UK?

8 min read

Lucy MacKinnon

Why was cannabis banned in the UK?

Historians and researchers have worked to unveil the complex history of the cannabis plant within the UK, from its cultivation and consumption, to its numerous changes regarding legal standing. We know that cannabis hemp plants were grown relentlessly in the UK for industrial purposes during the reign of King Henry VIII, and were often made into ropes, bindings, and sails used by the British Navy.


Around 300 years later came the emergence of cannabis-based medical treatments. The practice of using cannabis medicinally is said to have been introduced to Britain in the 1830s by the Irish Physician, William Brooke O’Shaughnessy after he returned from studying in India. When cannabis became commonly used, the public became aware of its intoxicating effects, and somewhat unsurprisingly, recreational applications followed.

Up until the start of the twentieth century, cannabis consumption was completely legal in the UK and was even reportedly consumed by members of the Royal Family. So, you may be asking, ‘Why was cannabis banned in the UK?’

Gradually, pressures surrounding international drug reform grew, and the topic was debated amongst the League of Nations. Initially, delegates from the United Kingdom opposed the criminalisation of cannabis because the production and cultivation of hemp played a large role in the economic stability of the British Empire. However, due to fear and political pressure, in 1928 the UK agreed to conform with its allies and prohibited recreational cannabis use.

Why was cannabis made illegal in the UK in 1928?

The two main reasons for the ban on cannabis in the UK are simple: fear and pressure. British policymakers feared counterculture movements that challenged traditional values, and there was also fear of being estranged politically from European allies. At the same time, Britain was facing building pressure to follow in the footsteps of other powerful countries and fulfil their obligation in drug reform, as a member of the League of Nations.

On the 9th of January 1920, The UK announced the creation of The Dangerous Drugs Act, their first attempt at drug reform, in a memorandum issued by The British Home Office. The law came into effect in September 1920 and restricted the use of certain drugs exclusively to medical practitioners, who were allowed to prescribe cocaine, heroin, and morphine in certain circumstances that they deemed appropriate. In 1928, this act was amended and cannabis was added to this list, this was to fall in line with the treaty the UK signed at the 1925 International Opium Convention which criminalised the recreational use of cannabis.

The International Opium Convention eventually came to the decision to regulate cannabis after it was proposed by Egyptian officials in 1924. Some accounts report that delegates agreed to the reform because they didn’t know much about cannabis, whilst others say it was to speed up debates to reach their original topic: opium. Regardless of why this was decided - because this agreement was signed by every member of the League of Nations, each country then had a responsibility to impose restrictions and regulations on cannabis usage.

The moral panic surrounding cannabis use was amplified within the media, which continued to perpetuate anti-cannabis messages. In 1936, the infamous US propaganda film Reefer Madness came out and was quickly broadcast around the world with a range of different titles. 

Originally commissioned by an American church under the name Tell Your Children, this, now highly parodied, propaganda film served as a morality tale, spouting untruths about the dangers of cannabis. This film is argued to have influenced the enforcement of the US Marihuana Tax Act in 1937 which prohibited recreational cannabis use, and then made its way around the globe to influence parents and politicians.

The 1960s and the rise of counterculture

During the 1960s and 70s, anti-cannabis sentiment began to spread across Britain. The plant’s association with youth rebellion, the hippie movement, alternative celebrities, and immigrant subcultures, challenged traditional social constructs and values within the UK and instilled fear in lawmakers. Large anti-cannabis propaganda campaigns about the use of cannabis contributed to moral panic and institutionalised racism, as well as the enforcement of stricter regulations surrounding the cannabis plant.

In 1964 the Dangerous Drugs Act was amended again, this time banning the cultivation of cannabis in the UK to coincide with decisions made at the 1961 UN Convention on Narcotic Drugs. Three years later in 1967, this law was altered again to allow only doctors who had been licensed by the Home Office prescription rights to restricted drugs, which included cannabis.

These strict laws caused a stir in cannabis activism, and the counterculture movement campaigned in full force to try to achieve the liberalisation of drug laws. One example that gained large scale attention was a full-page advert printed in The Times in 1967. This ad was a petition addressed to the Home Secretary asking him to implement a five-point programme for cannabis law reform, which was signed by every member of The Beatles.

Modern day prohibition

A few years later, in 1971, the British Government unveiled their latest prohibition proposal: The Misuse of Drugs Act. This Act categorised different narcotic drugs into schedules and classes, establishing a hierarchy of perceived harm or danger, and became fully operational in 1973. Cannabis and cannabis resin, cannabinol, and cannabinol derivatives are all listed as Schedule 2, Class B drugs.

In 2002 The Misuse of Drugs Advisory Council recommended the classification of cannabis should be reconsidered, and two years later in 2004 the status of cannabis was officially changed, making it a Class C drug. This was decided on the grounds that the potency and inherent toxicity of cannabis are disproportionate in relation to the other substances categorised in Schedule 2, Class B, such as amphetamines or ketamine.

However, not everybody agreed with this decision and many campaigned for this decision to be reversed. In 2009, cannabis was rescheduled again back to class B, and later that year a £2 million national anti-cannabis campaign was rolled out, with adverts featuring on prime-time TV and radio slots.

Currently, in the UK, cannabis is classed a Schedule 2, Class B drug. Although medical cannabis was legalised in the UK in November 2018, this only protects patients with a valid prescription from prosecution. Patients who are self-medicating or people using cannabis recreationally can be sentenced to up to five years in prison if they are found to be possessing cannabis. Those found to be cultivating or supplying street cannabis can receive a 14-year prison sentence.

Recent developments in the political climate

Since the legalisation of medical cannabis in the UK, certain political parties have proposed the legalisation of recreational cannabis. In 2019, The Green Party updated their drug policy to show its support for the decriminalisation of possession and cultivation of cannabis. 

Should they win a general election, The Green Party announced they would allow small businesses to sell cannabis, grant licences to cannabis social clubs and make herbal cannabis available on NHS prescription.

The Liberal Democrats are another British political party advocating to change the strict laws surrounding cannabis. The Lib Dems suggest a legal, regulated cannabis market for those over the age of 18. By enforcing potency restrictions and a licencing system for cannabis outlets, this party argues crime rates will diminish because criminal gangs will have less power.

In 2020 the public sent a petition to the British Government, appealing for the legalisation of cannabis across the board for all adults over the age of 18. The home office issued a statement in reply that read:

“The Government has no plans to legalise cannabis for recreational use. There is clear scientific and medical evidence that cannabis is a harmful drug which can damage users’ mental and physical health.”

Even with the support of smaller political parties like The Green Party and The Liberal Democrats, and a host of data that demonstrates the economic benefit the legalisation of cannabis could potentially cause, such as reports from the Institute of Economic Affairs, the British Government have remained firm on their stance towards recreational cannabis consumption.


The introduction of medicinal cannabis to the UK in the 19th century, and its subsequent journey through strict laws and regulations that have shaped our current political climate, has been a long one. It is clear that anti-cannabis sentiment continues to be prevalent amongst British lawmakers, even with recent developments such as the legalisation of medical cannabis. 

So, while cannabis may never be totally decriminalised, it is likely that attitudes towards its use will continue to shift over time. 

If you need an alternative approach to manage your health condition, Releaf is here to help. Our monthly packages are based on your cannabis prescription, and we offer specialist consultations for medical cannabis and a unique medical cannabis card for protection. 

It is important to seek medical advice before starting any new treatments. The patient advisors at Releaf are available to provide expert advice and support. Alternatively, click here to book a consultation with one of our specialist doctors.

Elevate your wellness with medical cannabis

Get comprehensive care, convenience, and confidence with an all-in-one treatment plan.

Check your eligibility

With five years of journalism and healthcare content creation under her belt, Lucy strives to improve medical cannabis awareness and access in the UK by producing high quality, credible content.

Our articles are written by experts and reviewed by medical professionals or compliance specialists. Adhering to stringent sourcing guidelines, we reference peer-reviewed studies and scholarly research. View our editorial policy.

Further reading

The Continental Cannabis Guide: Medical cannabis-friendly countries

For some patients, medical cannabis really is a lifeline and is therefore a necessary component in the holiday of a lifetime. So that you don’t have to choose between your health and a holiday, we’ve put together this guide that explains which countries currently have medical cannabis policies in place.

Lucy MacKinnon

Medical cannabis on holiday: The basics

Here at Releaf we understand that holidays should be about relaxation, but travelling with medical cannabis sounds like a stressful voyage. We’re doing what we can to absorb that stress so that you can soak up the sun, and so, we’ve designed a series of articles to cover the subject: medical cannabis on holiday. 

Lucy MacKinnon

How long does it take to feel the effects of THC oil?

The time it takes for you to feel the effects of THC depends on the methods of administration as well as your own physiology. Fortunately, there are fast and slow-acting options, as well as ways to take low or high doses in order to facilitate control over the way your body reacts to your medicine.

Editorial Team