Monia Mazigh speaks with reporters on Saturday.
(CBC)

Demonstrators in about a dozen Canadian cities Saturday demanded an end to "secret trials" and the controversial security certificate process after the federal Conservatives signalled in last Tuesday's throne speech plans to introduce new measures to the country's anti-terrorism laws.

Activists in Ottawa accused the government of crafting a "two-tiered" justice system after the Conservatives vowed in the throne speech to respond to the Supreme Court decision on security certificates through legislation that would add new measures to the Anti-terrorism Act.

"My concern is that the new legislation will not provide the immigrants and the non-status people with a fair trial," Monia Mazigh told a crowd of about 60 people gathered at a human rights monument in downtown Ottawa. "We never expected something like this."

Mazigh led a public fight to free her husband, Maher Arar, from a prison in Syria, where he says he was tortured while being held for nearly a year.

Arar, an Ottawa telecommunications engineer, was detained during a stopover in New York in 2002 by U.S. officials who claimed he had links to al-Qaeda. They later put him on a flight to Syria. He was not present at the Ottawa event.

The demonstrators called on Public Safety Minister Stockwell Day and Immigration Minister Diane Finley to immediately withdraw all security certificates that have been issued and to release detainees currently in jail or under house arrest.

They also demanded an end to deportation proceedings against five men being held under security certificates.

In an e-mail to the Canadian Press, Day's communications director, Melisa Leclerc, wrote that the Conservatives plan on bringing forward legislation in the coming week to "address the particular issues the Supreme Court has asked the government to give attention to.

"The only way a person could be subject to a security certificate would be a person that is not a Canadian citizen who represents a serious threat to Canada," she wrote.

She also took a shot at the Liberals, calling them "soft on terror," while insisting the Conservatives "will not waiver when it comes to safeguarding the security of Canadians."

In February, the Supreme Court overturned the current system of security certificates used by Ottawa to detain and deport non-citizens on public safety grounds, saying it violates the Charter of Rights and Freedoms.

The country's highest court also suspended the full legal effect of the ruling for one year, giving legislators time to rewrite the law and comply with constitutional principles that guarantee fundamental justice and prohibit arbitrary detention.

At a rally outside a CSIS building in downtown Toronto Saturday, organizer Matthew Behrens questioned the credibility of the "secret evidence" CSIS has on the security certificate detainees, given the revelations that arose out of the Arar and Air India inquiries about how CSIS operates.

Rallies were held in Ottawa, Toronto, Montreal, Edmonton, Vancouver, Fredericton and Halifax, and the Ontario communities of Kitchener-Waterloo, London, Durham, Orillia, Midland and Sudbury.