Security certificates and secret evidence
CBC News, Updated: September 5, 2012

What is a security certificate?

It is a legal tool that allows the Canadian government to detain and deport permanent residents or foreign nationals considered to be a security threat using secret evidence that the accused is not allowed to see. The certificate’s use is outlined in the Immigration and Refugee Protection Act.

… The certificates have been part of Canada’s immigration law since 1978. Since 1991, at least 29 security certificates have been issued …

On Feb. 23, 2007, the Supreme Court of Canada unanimously voted 9-0 that the security certificate system was unconstitutional, but suspended judgment for a year so that Parliament could draw up a new law ….

Lawyers for lead litigant Charkaoui and two other detainees — Harkat and Almrei — had argued before the court that security certificates locking people up without charge violated both Canadian and international law …