Uruguay legalized marijuana in 2013. Canada legalized it last week. In doing so, both countries put themselves in clearly violation of the UN anti-drug treaties that are the legal backbone of global drug prohibition. The US arguably continues to do so through state-level legalization accommodated by federal practice.

Not much has happened. That's because the treaties are toothless; they have no effective enforcement mechanisms that apply to most countries. If a country that grows opium for the global medicinal market, the International Narcotics Control Board can threaten to revoke its rights under the global quota system, for example. But while the global anti-drug bureaucrats at the INCB can write irate memos criticizing Ottawa and Montevideo, that's about it. They have done so, and Canada and Uruguay have blithely ignored them.

Still, the 1961 UN Single Convention on Narcotic Drugs and its 1971 and 1988 follow-ups are global agreements, and while an argument can be made that countries that want to legalize marijuana or other drugs should just ignore that provision -- say, on the basis that they are prioritizing the human rights treaties -- there is a counterargument to be made that it is better to modify or creatively interpret the existing global framework than to merely brush aside the anti-drug treaties.

The good folks at the Transnational Institute's (TNI) Drugs and Democracy program have come up with what they call "an elegant way" to end global prohibition agreements. It's called inter se modification. Instead of ignoring the tension between national-level legalization and the treaties, using this strategy would "resolve those treaty tensions and enable progressive and sustainable change at the global level."

What inter se modification does is allow two or more signatory states to the UN conventions to enter into an agreement among themselves alone. As TNI explains in the video below, a group of countries -- say Canada, the Netherlands, and Uruguay -- could agree to an inter se modification agreement on how marijuana cultivation should take place, how international commerce should be conducted, and education and public health policies, among others.

"These three countries would basically create a mini-treaty of their own, while at the same time respecting the rights and obligations of all state parties that do adhere to the UN drug control conventions," TNI explains. "If other countries wish to legally regulate cannabis after this mini-treaty is agreed on, they are free to join the group and enjoy the benefits accordingly."

Here we have a way to legalize marijuana or other drugs at the national level which at least acknowledges what the UN treaties say about that, and which seeks to minimize the tension that legalization generates in the treaty system. The treaties' provisions calling for prohibition would simply be hollowed out over time as country after country eventually joins the inter se modification agreement. Maybe then there will come a tipping point where the treaties themselves can be amended to reflect the new global reality.

Here's how TNI explains it all: