What pot-smoking Canadians can expect when crossing the U.S. border

Although cannabis is becoming legal in Canada, its use and possession remains a federal crime in the U.S. That can pose problems for Canadians crossing the border. Canadians who admit to American customs officers that they have ever used marijuana can be denied entry or be banned from the U.S. for life. The border prohibition applies even to Canadians authorized to use cannabis for medical purposes.