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Harvesting madness: the unintended consequences of cannabis prohibition

posted on 2023-06-09, 22:01 authored by Nicholas Sinclair-HouseNicholas Sinclair-House
The global prohibition of Cannabis was comprehensively enshrined in the 1961 UN Single Convention on Narcotic Drugs, a measure rooted in the unfounded belief that it was a drug with no medical benefit which was known to cause mental illness. This association with insanity was promulgated in significant measure by the US administration during the early 20th century as part of its drive to form international consensus in favour of prohibition. Criminalizing the drug had the inadvertent effect of promoting domestic production over import in Western countries, as clandestine cultivators in these traditionally non-producer nations sought to breed varieties which would flourish in cooler northern climes. Though representing very different interpretations of the 1961 Single Convention, the US and Dutch prohibition regimes acted in concert to accelerate this process, resulting in domestically-produced, hybridized ‘Skunk’ Cannabis variants which quickly found favour throughout the Western world due to the facility of their clandestine domestic production and their markedly increased potency. Cannabis producers in the West have seen the advantage in selectively breeding in favour of significantly increasing the amount of THC present in the plant. However, increasing THC comes at the cost of reducing the amount of Cannabidiol, a potent anti-psychotic, leading to speculation that this changing ratio is impacting the mental health of users. It is this new form of Cannabis which almost exclusively dominates the medical and latterly recreational marijuana market in the US today. It is also this new form of Cannabis which has been the subject of scientific scrutiny for its genuine, demonstrable link to mental illness. Prohibition, founded in large part on the false association of Cannabis with mental illness, is directly responsible for its metamorphosis into a drug which genuinely merits this association. Any move to revisit Cannabis regulation must take account not only of the increased potential for harm emerging from its modern guise, but, crucially, also consider that the one thing guaranteed to perpetuate the trend is continued criminalization.


Publication status

  • Published


AJOB Neuroscience

Presentation Type

  • other

Event name

International Neuroethics Society Annual Conference

Event location


Event type


Event date

22-23 October 2020

Department affiliated with

  • Sociology and Criminology Publications

Research groups affiliated with

  • Sussex Addiction Research and Intervention Centre (SARIC) Publications
  • Crime Research Centre Publications

Full text available

  • No

Peer reviewed?

  • Yes

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