Absolutely not; we don't need a warrant to speak to Canadians. What we need is a suspicion that leads us to believe they might present a danger to public safety. We don't have lawyers because this isn't a criminal investigation. We talk to people; we can't arrest them or put them in prison or file criminal charges against them. What we can do with them is talk to them. In those circumstances, we don't need lawyers.
Evidence of meeting #17 for Public Safety and National Security in the 40th Parliament, 3rd session. (The original version is on Parliament’s site, as are the minutes.) The winning word was information.
A recording is available from Parliament.