In Canada, Liberal Leader Justin Trudeau's call for legalization has spurred the discussions, while in the United States, it's Colorado and Washington moving in that direction and Alaskans voting next year on doing so.
Internationally, Uruguay is close to becoming the first country to legalize pot, although in most countries it was legal until some time in the 20th century.
Eleven years ago today, a Senate committee issued a major report recommending that Canada legalize marijuana, as well as explaining how to go about it.
"Whether or not an individual uses marijuana should be a personal choice that is not subject to criminal penalties, but we have come to the conclusion that, as a drug, it should be regulated by the state much as we do for wine and beer," committee chairman Pierre Claude Nolin said at the time.
Eleven years later, the Conservative Senator tells CBC News he still stands by his committee's report. "The public is already there," Nolin observes, adding that the challenge is with the politicians.
Washington, Colorado experiment with legalization
Since then, Liberal governments twice took steps on changing marijuana laws (which went nowhere), while Colorado and Washington voters opted to legalize recreational marijuana use.
In March, Washington state named UCLA drug policy expert Mark Kleiman its marijuana guru. He sees an advantage for Canada "to hang back and see how the experiment comes out" in the two states.
But not for long. "We'll know a lot more two years from now than we know now about the risks and benefits," he tells CBC News. Kleiman does not think "legalization is going to be any screaming triumph."
David Malmo-Levine, one of Canada's best-known pot activists, says legalization will be easy. "The right way to legalize marijuana is to focus on the legitimate concerns of harm from misuse of marijuana and of excluding people from the market."
The harms he has in mind are impaired driving and health problems from substandard, mouldy or contaminated cannabis.
Decriminalization not a recommended route
Nolin, Kleiman and Malmo-Levine all say that decriminalization as an interim measure is not the route to take toward legalization.
Even though he notes that about 60,000 Canadians face possession charges every year, Nolin says "I would keep the bad system we have, keeping in mind we must change it."
"We're kidding ourselves with decriminalization, because we're keeping it illegal" he argues, and that makes it more difficult to prevent problematic use.
Decriminalization would be equivalent to prohibition of alcohol in the 20th century and Kleiman notes that certainly wasn't a success.
He also says decriminalization would do nothing to get rid of the illicit market, have very little impact on consumption or address the issue "about people getting products that are completely untested, unlabelled, with no idea about what's actually in them."
"I'm not sure inching in through decriminalization matters one way or the other," he argues.
Malmo-Levine, who has studied the international record, says "decriminalization is worse than nothing at all." His view is that "harmless people don't need to be harmed less, they need to stop being harmed."
Applying a wine model to marijuana
Malmo-Levine also favours using a system similar to what Canada has in place for wine, at least initially, for marijuana legalization.
He says parents would be able to set the rules over their teenage children's use and, as with wine, there would be no monopoly on production or sales. People would be able to grow their own marijuana, the same way they can make their own wine at home or at a commercial operation.
Kleiman sees some problems with the wine model. He wants liquor boards to "take a much broader view of the public interest and hold themselves accountable for the total damage done by alcohol, both drunken misbehaviour and the health consequences of heavy drinking.
"And I think that applies to cannabis as well."
He's against "a purely commercial market in cannabis, like the one we now have with alcohol," because he expects it would result in the same pathologies. "I would much rather have people grow their own or form co-ops or get it from a state monopoly, where the people in charge won't have a strong vested interest in fostering addiction."
He recommends Canada allow private cultivation, but require that growers only sell their cannabis to the government retailer. That idea sounds like the old Canadian Wheat Board.
The advantage of this approach, Kleiman says, is the state can keep control of the marketing effort and hinder "the development of an economically and politically powerful industry that then can't be moved, like the existing beer industry."
He lists off some more advice. "You want to keep the price high, you want to keep the marketing down, you want to make sure that consumers know what they're getting, not just in the sense of knowing what the chemistry is, but knowing what the likely effect is, so I'd want to have very strong vendor training in place."
A binding quota for pot users
Kleiman also recommends requiring marijuana consumers to set a binding quota for how much they can buy each month, though they would be able to revise their quota with a month's notice.
"Cannabis is not a bad habit for most people who use it, any more than food is but ... we shouldn't have a laissez-faire approach towards selling it" because a limited number of people will have their bad habits run away with them.
Kleiman and Malmo-Levine both stress the need for a system of quality control, both for impurities such as pesticide residues and mould, and for the active agents in the cannabis. That requires testing and labelling.
As he did in the 2002 Senate report, Nolin today recommends that as a first step toward legalization the prime minister should appoint a special envoy on marijuana (and all psychoactive substances) who would join the Privy Council Office and convene a conference of key stakeholders. Canada should also seek amendments to United Nations conventions and treaties governing illegal drugs.
As for legislation, in the words of the report, it "should stipulate the conditions for obtaining licences as well as for producing and selling cannabis; criminal penalties for illegal trafficking and export; and the preservation of criminal penalties for all activities falling outside the scope of the exemption scheme" for cannabis.
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