They could declare users inadmissible - perhaps for life. He also noted that sniffing dogs can smell residue weeks after it's been used so people crossing should not lie if the questions are asked.
Canada is set to become the world's only major industrialized nation to legalize retail marijuana sales, starting October 17. Owen said if travelers lie about past drug use during questioning, that's "fraud and misrepresentation, which carries a lifetime ban".
Not every traveller will be asked whether they use marijuana, but Owen also outlined several signs of pot use that officials will not ignore.
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The Ravens defense shot themselves in the foot with penalties, committing four on third-down, three of which extended drives. It wasn't fancy, but they exploited matchups against the Bengals linebackers who struggled in coverage.
Meanwhile, during an interview with CBC Manitoba earlier this week, Prime Minister Justin Trudeau said the federal government is working with us officials to ensure that travel to the States doesn't become an issue when marijuana is legalized in Canada next month.
He will then be giving the opportunity to "voluntary withdraw" from the border-or face "expedited removal".
Owen gave Politico a detailed preview of how the US Customs and Border Protection agency will continue to apply long-standing US federal laws that treat marijuana as a banned substance and participants in the cannabis industry as drug traffickers. The waivers are only granted at the discretion of CBP.
"I think it's incredibly risky for someone to [lie], especially if they are somebody who works in the industry and their affiliation with the industry is readily available online", said Enenajor.
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Now more than ever, sport has gone from recreation for the masses to a battleground in the increasingly unavoidable culture war. Williams was issued a warning for coaching, something her coach sitting in the stands, Patrick Mouratoglou, admitted to doing.
Anyone who travels to the USA regularly knows that a common question at the border is "what do you do for a living?"
"We don't recognize that as a legal business", Mr. Owen added. "Facilitating the proliferation of the legal marijuana industry in USA states where it is deemed legal or Canada may affect an individual's admissibility to the U.S.".
"I wouldn't presume to have any other country tell me how or who we can let into Canada, and I certainly won't work to assume to impress upon the USA who they have to let in or not".
"A lot of people don't understand that they are still going to have problems after legalization", said Henry Chang, a partner at Blaney McMurtry LLP in Toronto who handles immigration law on both sides of the border. Justin Trudeau's government and travel agents are warning Canadians to make sure they have no trace of the drug in their cars or luggage.
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Boarding up his home in Myrtle Beach, South Carolina , Chris Pennington watched the forecasts and tried to decide when to leave. In other words, this hurricane will basically stall - pounding the same parts of the Carolinas over and over again.