In a brief to the UN committee, the human rights group says it is "profoundly concerned" that Canada has not heeded the committee's call to provide redress to Abdullah Almalki, Ahmad El-Maati and Muayyed Nureddin.
The three Arab-Canadians were brutalized in Syrian prisons, in part due to lapses by Canadian agencies documented by a federal inquiry in 2008.
All three are suing the federal government, though the cases have dragged on in court for years.
In a June 2012 report on Canada's compliance with the United Nations Convention against Torture, the UN committee recommended Ottawa "take immediate steps" to compensate the men.
However, the government is no closer to making reparations, said Alex Neve, Amnesty International Canada's secretary general.
"At every turn since then, what we have seen is defiant insistence on the part of Canada that they will do no such thing," Neve said Wednesday in an interview.
"All we've seen over the past year is further obstruction and unwillingness on the part of the government in various court appearances and court applications — refusing to hand over documents and battling every motion and application up and down the court system in as protracted and drawn-out a manner as possible."
At a court hearing on the cases last year, federal lawyers argued the UN convention was irrelevant to the legal proceedings, pointing instead to Canadian civil law.
In its report last June the UN committee also criticized planned federal measures affecting refugee claimants, which have since become law, as well as the continuing use of national security certificates to detain non-citizens suspected of terrorism or espionage.
In addition, it chastised Canada over a ministerial direction to the Canadian Security Intelligence Service allowing the spy agency, in some cases, to use information that may have been gathered through torture, or to share information even if it might lead to abuse.
It later emerged that Canada had sent similar directives to the RCMP and the Canada Border Services Agency.
"The government has taken no steps to revise these directives to bring them into conformity with international human rights requirements," says Amnesty's brief.
The committee asked Canada to provide followup answers to key concerns and recommendations by June 1 of this year. It plans to hold a meeting Friday in Geneva to review Canada's progress.
Canada insisted during an appearance before the committee in May 2012 that it is aware of — and takes seriously — its international treaty obligations.
Neve said that with the exception of Omar Khadr's return from the U.S. naval base at Guantanamo Bay, Cuba, Canada has not acted on the committee's June 2012 report.
"Not only have we not seen progress towards compliance with the recommendations the committee's made, in many respects the concerns have worsened since the review," Neve said.
As of late Wednesday, the UN had not posted Canada's latest written representations to the committee.