As cultural attitudes change, governments around the world are looking to update their policies on drugs more generally.
Uruguay, a small nation of around 3 million people in South America, set a global precedent when former president Jose Mujica signed a law to legalise marijuana in December of 2013.
The global shift on drug policy even includes conservative countries like Lebanon, which is seeking to legalise medical marijuana after the consulting firm McKinsey suggested it as an approach to revitalizing the country's sluggish economy.
Colombia, which has suffered from decades of narco-related violence, took a different approach: rather than legalizing marijuana and other drugs outright, the country made it unconstitutional to criminalise the consumption of any drug.
"There is a major shift in approaches to medical marijuana across the Americas," Robert Muggah, the co-founder and research director of the Igarapé Institute, told Business Insider.
"Almost every country in the Americas recognises the medical potential of the plant. This is more radical then it seems."
These are the five countries with the most progressive drug policies in North and South America according to the Igarapé Institute, a Brazilian think tank that focuses on drug policy and security:
Uruguay became the first country to legalise marijuana in December 2013 after former President Jose Mujica signed the legislation.
While it broke new ground as the first country to legalise the drug at the federal level, Uruguay's roll-out of a recreational marijuana industry has been bumpy, to say the least.
According to John Hudak, an expert on cannabis policy at the Washington DC-based Brookings Institution, Uruguay's legal cannabis providers have been marked by supply shortages and distribution problems, forcing some consumers to rely on the illegal black market.
Canada made history in June when it became the first G7 nation to legalise marijuana at the federal level. While the law doesn't go into effect until October 17, countries around the world are watching Canada's rollout closely.
"Canada's decision to legalise marijuana is unprecedented among wealthy nations," Muggah, the co-founder and research director of the Igarapé Institute said.
Canada's legal marijuana industry has already given rise to large public corporations that are inking billion-dollar deals to sell and export Canadian marijuana all over the world. And because of the federal government's coherent stance on marijuana, big banks, and major institutional investors are jumping into the industry.
It remains to be seen, however, whether Canada's marijuana policy can achieve the stated goals of reducing youth access and keeping marijuana consumers from turning to the black market.
On top of that, another 30 states have some form of medical marijuana laws on the books, including Oklahoma, one of the most conservative states in the US.
Neither Congress nor President Donald Trump's administration have legalised marijuana at the federal level (though there are a number of bills circulating around the House and Senate), so some questions still remain over whether the US will legalise marijuana outright.
While multiple states have set up successful markets for recreational marijuana, Muggah said that some policies lack proper consideration for communities who were hurt most by drug prohibition.
"While there have been important advances on the public health front, states and cities across the US are still lagging when it comes to criminal justice reform," Muggah said.
Colombia has been a leader in experimenting with different approaches to drug policy for decades.
The country has long struggled with violence resulting from black market cocaine and marijuana consumption. Prohibition didn't help.
So in 1988, Colombia became one of the few countries to back out of the United Nations' Narcotics Convention, a document that escalated the prohibition approach to drug manufacturing and consumption.In 1994, Colombia made it unconstitutional to criminalise the consumption of all drugs.
Colombia does not yet have legal marijuana.
Chile's government recognised the medicinal value of marijuana in 2013.
As of this year, Chileans are permitted to grow up to six plants per household and possess up to ten grams for personal consumption – as long as they have a prescription from a doctor, according to the Igarapé Institute.
Chile has the highest cannabis consumption rates per capita of any nation, according to Marijuana Business Daily, a trade publication.
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This article was originally published by Business Insider.
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