Portugal’s drug problem began almost as a symbol of freedom, experimentation that was impossible before the country’s oppressive dictatorship ended 40 years ago. By the late 1990s, that rebellious dabbling had turned into a full-blown national addiction crisis.

One of every 100 Portuguese — 100,000 citizens — was on heroin, users were dying regularly and rates of HIV infection from dirty needles stood among the highest in Europe.

“It was a catastrophic situation,” Joao Goulao, a physician who treated many of those addicts, recalled in an interview this week. “You could see people everywhere using drugs … It was almost impossible to find a Portuguese family that did not have (drug-related) problems.”

Then, 15 years ago, Portugal came up with a response seemingly more dramatic than the actual problem: it decriminalized every illicit drug, from marijuana to cocaine and heroin.

Caught with less than a 10-day supply of any narcotic today, the worst a user can face is the equivalent of a speeding ticket. It’s more likely he or she will be diverted into treatment, and furnished with harm-reduction services like hypodermic exchanges.

As Canada’s Liberal government prepares to make its own mark in the drug world — legalizing possession of marijuana — Goulao was in Ottawa this week. Now head of his country’s addictions agency, he met with government and law-enforcement officials and spoke to activists, describing what many experts view as the clear dividends of Portugal’s eye-opening reforms.

Indeed, the rates of overdose and other drug-related deaths, of HIV infections from contaminated hypodermics and of narcotic use overall have fallen since 2001, when decriminalization was implemented alongside an array of other programs designed to improve treatment and curb poverty.

“There’s no doubt that it has been a success,” says Richard Elliott, executive director of the Canadian HIV/AIDS Legal Network. “There is no doubt that it has important lessons for other countries, including Canada.”

Goulao addressed a conference on Friday in Toronto on drug-law reform, where another of the speakers was Health Minister Jane Philpott, tasked with helping craft the government’s pot-legalization initiative.

Until recently at least, Canada had actually been moving in the opposite direction to Portugal, with the number of drug prosecutions increasing, half the 109,000 charges in 2013 for simple marijuana possession, according to Statistics Canada.

What the Trudeau government is proposing is both more radical than Portugal’s policy — complete legalization — and more limited, applying to only one illicit product and ignoring the hardest drugs.

But it flows from the same basic idea: to shift away from the prohibitionist approach that prevails in most of the world and treat drug use as a public-health problem. When users are not faced with criminal records and jail time, the theory goes, they are more likely to seek and receive help and take fewer risks.

Urged on by Mexico and other countries devastated by drug wars, a special session of the United Nations general assembly debated such concepts in April, though ultimately did little to alter the status quo.

Portugal became a sort of social laboratory where we developed this experiment

Even in Portugal, not everyone is convinced decriminalization makes sense.

Manuel Pinto Coelho, a Portuguese treatment doctor, has said the new law only encouraged drug dealers, who brazenly offer their wares on popular Lisbon streets.

“Such daring characters were inexistent five years ago in places like these,” he wrote in a 2011 paper.

And he says he has seen no evidence that criminal prosecution keeps addicts away from the help they need, and yet does act as a deterrent.

Goulao says Coelho’s criticisms put him in the minority in Portugal now, and notes there was tremendous pressure 15 years ago to take strong action on what was the country’s leading political issue.

“We had nothing to lose, so Portugal became a sort of social laboratory where we developed this experiment.”

If drug users are “intercepted” by police now and have less than a 10-day personal supply, they are delivered to a three-person “commission for the dissuasion of drug addiction.”

The panel can levy fines or community service but also tries to get to the bottom of the person’s drug problem and prescribe a response, from methadone treatment to better housing and mental-health services.

Alex Stevens, a criminal-justice professor at Britain’s University of Kent, says he has tried to take a “nuanced” approach to analyzing the hotly debated reforms — and still found a mostly positive effect.

Drug-caused deaths in the population of 10 million have plummeted from close to 80 a year in 2001 to less than 20, a rate far below the European Union’s average, he reports. The number of new HIV infections due to intravenous drug use has also plunged — from more than 1,000 in 2001 to less than 100 in 2013.

The actual use of drugs overall did appear to climb in the first years, but has since decreased, while the number of “problematic” users — cocaine and heroin addicts — has declined steadily, said Stevens.

Back in Canada, the Liberal plan seems to go beyond the European country’s criminal-justice changes, and yet misses out on the “creative” measures it took to improve addicts’ lives, argues Kevin Sabet, a former White House advisor and head of SAM, an anti-marijuana-legalization group.

Proponents of more liberalization actually agree that a package of programs — not just changing the criminal law — is essential, but stress that Portugal’s reforms spoke particularly loudly about treating drug use as a crime.

“As one of my colleagues said: ‘The most important thing about the Portuguese model is that they did this (decriminalization), and nothing bad happened,’ ” says Donald MacPherson, director of the Canadian Drug Policy Coalition. “In fact, good things happened.”

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