The response from the Harperites has been both swift and predictable, at a time when even the Canadian Association of Chiefs of Police (see video below) are advocating handing out tickets for pot possession:
Justice Minister Peter MacKay said that smoking pot as an MP demonstrated "a profound lack of judgment" on Trudeau's part.
"By flouting the laws of Canada while holding elected office, he shows he is a poor example for all Canadians, particularly young ones. Justin Trudeau is simply not the kind of leader our country needs," MacKay said in a statement.
Meanwhile, you might like to read this AlterNet article that gives 10 frightening examples of why the 'war on drugs' is far too costly.
UPDATE: Many thanks to LeDaro for alerting me to this video, a discussion on Power and Politics about Trudeau's revelation. I couldn't help but note the short leash the party put Conservative M.P. Blake Richards on as he evades questions and only repeats points.