In Canada, the Arar affair spawned a lengthy judicial inquiry that probed state secrets. The findings led to a multimillion-dollar compensation package for a citizen unlawfully imprisoned overseas.
In the United States, judges have determined that Maher Arar's complaint of CIA "extraordinary rendition" is merely a potential case of "graymail" against Washington - the equivalent of blackmail against government agencies in the shades-of-grey intelligence world.
In dismissing the lawsuit known as "Arar v. Ashcroft" yesterday, a U.S. appellate court expressed fear that going forward could prompt dangerous disclosures of state secrets.
"This feature of such claims opens the door to graymail," a 7-4 majority of judges ruled. They explained the concept by saying that Washington could feel obliged to pay huge settlements simply out of fear that "any effort to litigate the action would reveal classified operations that might undermine ongoing covert operations."
The majority of judges added that, "it is not for nothing that Canada ... paid Arar $10-million."
A vocal - and seemingly outraged - minority on the Second Circuit complained that their colleagues' disregard for Mr. Arar's rights smacked of "utter subservience" to presidential authority.
Lost in the talk of "graymail," they said, was the suffering of a torture victim. "A person - whom we must assume a) was totally innocent and b) was made to suffer excruciatingly and c) through the misguided deeds of individuals acting under color of federal law is effectively left without a U.S. remedy," dissenting judge Guido Calabresi wrote.
The U.S. ruling amounts to the mirror image of the kinds of verdicts bedevilling security agents in Canada, who complain that judges tilt too much toward transparency. Last week, Canada's top spymaster lamented that his agency was all but forced to scuttle an important case (the so-called security certificate against Adil Charkaoui) after a judge ordered intelligence revealed.
"To disclose information, that would have given would-be terrorists a virtual road map to our tradecraft and sources," Dick Fadden said in a speech last week. "... We chose the path that would cause the least long-term damage."
In Canada, Mr. Arar's legal battles - which have prompted thorny secrecy battles - won him vindication and near-record compensation. Yet the U.S. agents who played a more direct role in his ordeal have never been held to account for branding him a terrorist and then putting him on a plane to face torture in a police state.
Extraordinary rendition - the U.S. practice of arranging to have presumed terrorists jailed and interrogated in third countries - remains a tool that agents of the president can use at will. The U.S. Central Intelligence Agency is often the unseen hand in rendition, a shadowy and "extra-legal" approach to fighting terrorism.
CIA renditions were pioneered by the Clinton administration, greatly expanded by the Bush presidency after the Sept. 11, 2001, terrorist attacks, and remain an option for the Obama administration.
The Second Circuit ruled yesterday that Congress, and not the judiciary, is best suited to rein in rendition. The decision had been anticipated for more than a year, since its judges decided to take a rare collective look at the case, which it had already once dismissed.
It has been five years since Mr. Arar, a Syrian-Canadian, launched his torture-by-proxy suit against former attorney-general John Ashcroft and other Bush administration officials.
After the Sept. 11 attacks, Canadian and U.S. officials branded the engineer a threat. In 2002, he was arrested in JFK Airport in New York while on his way to Montreal from Tunis.
Mr. Arar spent two weeks in U.S. custody before he was hustled onto a CIA jet.
For most of the next year, he was held in a Syrian prison - the facility where two other Canadian-Arab suspects had already ended up. A Canadian commission of inquiry led by Mr. Justice Dennis O'Connor found that Mr. Arar and the others were severely tortured during interrogations in Syria.
The judge found no substance to the suspicion Mr. Arar was an al-Qaeda member.