Section 34 of the Immigration and Refugee Protection Act provides that a permanent resident or foreign national is inadmissible to Canada for security reasons. It states:
34. (1) A permanent resident or a foreign national is inadmissible on security grounds for
(a) engaging in an act of espionage that is against Canada or that is contrary to Canada’s interests;
(b) engaging in or instigating the subversion by force of any government;
(b.1) engaging in an act of subversion against a democratic government, institution or process as they are understood in Canada;
(c) engaging in terrorism;
(d) being a danger to the security of Canada;
(e) engaging in acts of violence that would or might endanger the lives or safety of persons in Canada; or
(f) being a member of an organization that there are reasonable grounds to believe engages, has engaged or will engage in acts referred to in paragraph (a), (b), (b.1) or (c).
(2) [Repealed, 2013, c. 16, s. 13]
A Citizenship and Immigration Canada has produced a useful internal document summarizing the jurisprudence (up to about 2010) on the interpretation of this section, and I have reproduced it below. More recent jurisprudence can be found throughout my blog, but the CIC document is a very useful summary.
Please note that what I have reproduced below should not be viewed as legal advice. I obtained a copy of this internal Citizenship and Immigration Canada training guide through an Access to Information Act request (the “ATI”). The reproduction of question and answer has not occurred with the affiliation of the Government of Canada, nor with the endorsement of the Government of Canada. (I have decided not to reproduce the names of the Service Canada officers involved.) Please e-mail me if you want a copy of the original question and answer contained in the ATI.