Hilary Homes of Amnesty International Canada says the security certificate regime should be replaced with one that guarantees a fair trial and ensures no evidence extracted through torture is allowed.
Harkat, 44, was taken into custody Dec. 10, 2002, on suspicion of being an al-Qaida sleeper agent.
The Ottawa man denies any involvement in terrorist activities.
Security certificates have been used since 1991 to deport non-citizens accused of being terrorists or spies.
Harkat lives at home with wife Sophie, but wears an electronic tracking bracelet on his ankle, must check in with authorities regularly and cannot leave town without permission.
The person named in a security certificate receives only a summary of the case against them, which critics say makes a mockery of fundamental justice.
Harkat's case has been bound up in various legal proceedings since the former pizza delivery man's arrest.
NDP public safety critic Randall Garrison told a news conference Monday that detaining individuals for years without charge, trial or conviction "is not an acceptable practice in Canada."
Green party Leader Elizabeth May said security certificates violate "virtually every precept of our laws and system of human rights."
Harkat wiped away tears as his niece Gabrielle spoke of shopping for school supplies with her uncle while being followed by Canada Border Services Agency officers.
"I have heard many things about my uncle," she said. "But the only Moe I know cares about his family, is always there to help his neighbours, likes to cheer me on when I'm playing hockey."
The Supreme Court of Canada recently agreed to hear a challenge of the security certificate system brought by Harkat and his lawyers.
The hearing, likely to take place next year, will come more than five years after the Conservative government revamped the certificate regime in an effort to make it consistent with the Charter of Rights and Freedoms.
The government continues to defend security certificates, and notes they are used only in exceptional circumstances.
Two other security certificate cases — both originally from Egypt — remain before the courts.