Prime Minister Justin Trudeau agrees the minimum age to smoke marijuana should be 18 or 19, in line with each province's drinking laws, endorsing one of the most controversial recommendations from a federal task force on legalization this week.
Mr. Trudeau said the task force, which was chaired by former Liberal cabinet minister Anne McLellan, settled on the appropriate age to limit the role of the black market in Canada. With these comments, Mr. Trudeau rejected the calls of public health experts to set the minimum age in the early or mid-20s to protect developing brains.
"I think the proposal for the age of 18, or 19 in some provinces, to align with the [legal drinking age] across the country, is a reasonable compromise," Mr. Trudeau said at a news conference. "We know the main harm that comes from the consumption of marijuana occurs at a younger age than 18 or 19, and I think this is a reasonable approach that is balanced, practical and useful."
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Mr. Trudeau's statements indicate the Liberal government is in overall agreement with the task force's 80 recommendations.
"I want to thank the task force for the excellent work that they put in the report, to make recommendations on the best way to move forward while protecting our children from the easy access they currently have to marijuana, and to remove criminal elements from the marijuana market," he said.
The task force urged the government to allow Canadians to buy or carry 30 grams of marijuana for personal use, and to grow up to four plants at home. The system it recommended would feature storefront sales and mail-order distribution, and allow a wide range of producers to operate legally, including "craft" growers and the current producers of medical marijuana.
The Liberal government has promised to table legislation to legalize marijuana in the spring of 2017.
A senior federal official said the time frame for launching the recreational marijuana market in Canada will depend on the "readiness of the provinces," which will regulate wholesale distribution and retailing. The official said aiming for 2018 would be ambitious, with 2019 being more feasible.
Ms. McLellan's task force said an older age limit could fuel illicit sales of cannabis, as people between 18 and 24 are among the highest consumers.
Medical groups had argued against age 18.
The Canadian Medical Association, pointing out that the brain develops until about age 25, while acknowledging concerns about the potential black market, recommended a legal age of 21 as a compromise.
The Canadian Paediatric Society called for limits on the concentration of tetrahydrocannabinol in cannabis products available to people 18 to 25 because of its effect on developing brains. It expressed disappointment that no limit will be placed.
Regardless of the legal age, medical experts agree the federal government must adopt a strong public education and awareness campaign to counter the myth that marijuana is safe. A 2013 Unicef report found that Canadian youth are the highest users of cannabis compared with those of other developed nations.