Why do policies with the stated purpose of protecting national security often exclusively target non-citizens as security threats? This article examines how prevalent ideas about security and citizenship impact on the rights of non-citizens through an analysis of the Canadian security certificate procedure and the Supreme Court’s decision in Charkaoui. A multidimensional understanding of citizenship and statelessness shows that the security certificates detainees share complex vulnerabilities that remain unacknowledged in Charkaoui. Instead, Charkaoui reiterates and exploits the detainees’ rightlessness by placing them outside of Canadian society and investing them with a fictional agency in choosing between detention and deportation.