Amid the tragedy, it is difficult to miss the none-too-subtle jousting and positioning.
The Conservative government says the assault by a man who rammed into the pair with a car underscores the growing danger of homegrown radicalism — just as it prepares to introduce legislation to give Canada's spy agency more powers.
NDP Leader Tom Mulcair chided Prime Minister Stephen Harper for taking "everyone by surprise" by divulging unconfirmed information about the attack in the House of Commons a day earlier.
A backbench MP had asked Harper a scripted question, citing "unconfirmed reports of a possible terrorist attack" well before it was clear what had happened in St-Jean-sur-Richelieu, Que.
"A tragic event like the one in St-Jean-sur-Richelieu should be a moment to rise above partisanship," Mulcair said during the Commons question period Tuesday. "If this is an incident that threatens the national security of Canada, when will the government offer a full briefing to parliamentarians on this situation?"
Harper ducked the issue of a briefing and brushed aside any suggestion of political advantage, saying he informed the House "as soon as I learned of the situation."
Soon after, in response to Liberal Leader Justin Trudeau, Harper appeared to tie the events directly to the coming legislation.
"There are a number of individuals who are under surveillance for possible terrorist activities," Harper said, adding the government was examining ways to "give more tools to our security organizations to bring charges as soon as possible."
The government has raised its internal threat level due to an increase in "general chatter from radical Islamist organizations" such as the Islamic State of Iraq and the Levant, said Jason Tamming, a spokesman for the public safety minister.
This level means that intelligence has indicated that an individual or group within Canada or abroad has the intent and capability to commit an act of terrorism, but it is not the result of a specific threat, he added.
The government has already heavily previewed the coming bill — which could be tabled as early as Wednesday — touting it in a television interview and at a news conference in Banff, Alta., during the recent Commons recess.
The Conservatives plan to amend the law governing the Canadian Security Intelligence Service to give the spy agency greater ability to track terrorists overseas as well as take steps to ensure CSIS can protect the identity of its sources.
The proposed measures appear designed to address court rulings that went against the intelligence establishment.
A Federal Court judgment took CSIS to task for being deceptive about plans to rely on allies in the Five Eyes intelligence network to keep tabs on Canadian suspects abroad.
A Supreme Court decision on the national security certificate system — a tool for deporting suspected terrorists — said there should be no overarching privilege for CSIS sources.
The high court said the security certificate regime generally ensures that their identities remain "within the confines of the closed circle" formed by the reviewing judge, federal lawyers and special advocates — security-cleared counsel appointed to test the government evidence against a terror suspect.
Critics have expressed wariness about both ideas. They say denying judges and special advocates the opportunity to scrutinize CSIS sources in the closed-door setting could lead to a miscarriage of justice.
CSIS, on the other hand, would clearly welcome the changes. The spy service has pointed to the threat of homegrown radicals fighting overseas as justification for the new powers, including a source shield.
"The service relies extensively on information that is provided to us by human sources. We can't do our job without it," said Jeff Yaworski, CSIS's deputy director of operations.
Testifying at a Senate committee Monday, Yaworski said CSIS informants are "operating against some very nefarious groups" such as the Islamic State of Iraq and the Levant, whose members are terrorizing civilians in Syria and Iraq.
"So for them to discover a perceived traitor in their midst who is providing information or intelligence to CSIS would be extremely risky for that individual as well as that individual's family."
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