Even Toronto mayor Rob Ford says he's smoked pot.
Almost everyone on the political scene seems to have tried it, at one point or another, except for Stephen Harper.
The prime minister chuckled during a media scrum Thursday when asked if he too is part of the parade of politicians who've come out recently to concede they've smoked marijuana.
He took the opportunity to hammer Trudeau and the federal Liberals on the issue, accusing them of promoting pot use among children at the expense of developing an economic policy.
"Do I seem like I smoke marijuana?" Harper asked in response to a reporter's question.
"Ya know never know," the journalist replied.
Harper said his asthma precluded smoking.
"From a very young age, I have been an asthmatic and smoking anything has been out of the question since the time I was very small," he said during an event where he announced the introduction of legislation to better protect children against sexual exploitation.
The cavalcade of cannabis confessions was prompted by Trudeau's admission last week that he's smoked pot in the past, at least once since becoming an MP.
Since then, a bevy of other political leaders have joined the discussion, which has focused attention on a recent Canadian Association of Chiefs of Police proposal that marijuana possession be made a simple ticketing offence.
The association considers this would be more efficient than laying criminal charges, but it remains firmly opposed to decriminalization.
Harper said the government is studying the proposal very carefully.
He repeated his earlier criticism of Trudeau, saying the Liberal leader "displayed poor judgment" with his marijuana use.
"I look at the contrast with him promoting marijuana use for our children versus saying yesterday he will have no economic policy for several years," Harper said.
The debate comes as researchers published a new study, which concluded pot use may be riskier for teenagers than previously believed.
The research, conducted by the Universite de Montreal and New York's Icahn School of Medicine, says the nature of the teenage brain makes marijuana use particularly problematic and could lead to the development of addictive behaviours.
It reviewed more than 120 studies and concluded that pot use during adolescence interferes with natural brain development and may hardwire some addictions into adulthood.
Trudeau said that is precisely why he is proposing legalization because it would mean regulation and give authorities more opportunity to keep the drug from children.
"We're spending hundreds of millions of dollars a year on a plan that is not keeping marijuana out of the hands of our teens," Trudeau said, during a caucus retreat in Georgetown, P.E.I. "Instead, (we're) incarcerating and giving criminal records to hundreds of thousands of Canadians over the past few years in a way that's not useful, in any way, in keeping marijuana out of the hands of our teens."
—With files from Joan Bryden in Georgetown, P.E.I.
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