The government filed a statement of defence this week in a lawsuit launched by the B.C. Civil Liberties Association, which maintains much of the intelligence-gathering activity of Communications Security Establishment Canada, or CSEC, violates the rights of Canadians.
The lawsuit comes amid heightened scrutiny of the clandestine world of international spying, particularly in the United States, where a massive leak by former intelligence contractor Edward Snowden has offered an unprecedented look inside the National Security Agency.
Specifically, the association's lawsuit objects to instances in which foreign spying sweeps up Canadians' communications, as well as the collection of electronic metadata. Both activities, the group claims, violate the charter rights of Canadians.
CSEC is forbidden from intentionally collecting or analyzing information from Canadian citizens, whether they are in Canada or abroad.
However, the National Defence Act allows the defence minister to give CSEC written authorization to unintentionally intercept private communications while collecting foreign intelligence.
In those cases, CSEC can retain and use such communications "if they are essential to international affairs, defence or security," the government's statement of defence notes.
Such authorizations have been issued dozens of times in the past decade.
The federal government says it is impossible to know, in advance, whether foreign spying will inadvertently capture Canadians' private communications.
"Despite the fact that CSEC is directing its activities at non-Canadians outside Canada ... the complexity of the global information infrastructure is such that it is not possible for CSEC to know ahead of time if a foreign target will communicate with a Canadian or person in Canada, or convey information about a Canadian," says the government's statement of defence.
"There may be circumstances in which incidental interception of private communications or information about Canadians will occur."
The document said such activity is conducted within the law and with the rigorous oversight of the independent CSEC commissioner.
The statement of defence notes the minister issued 78 authorizations between 2002 and 2012, all of which were valid for a year and have expired. In 2013, four were issued, and they remain active.
As an example, the government says there were six authorizations issued in 2011.
Of those, five did not result in the interception of Canadians' private communications, the document says. The sixth authorization did capture a "small" number of private communications, according to the statement, though it doesn't offer specific details.
The collection of metadata is taking place under a ministerial directive, which, unlike a formal authorization, does not give CSEC any additional powers, the government says.
"The acquisition and use of metadata is critical to the fulfillment of CSEC's mandate," says the statement of defence.
The government says CSEC's foreign communications spying and its collection of metadata have prevented attacks against Canadians, both in the country and abroad, though it does not offer any specifics to back up that claim.
"CSEC's ability to acquire metadata, as well as its ability to carry out activities ... that risk the incidental interception of private communications, has contributed to the prevention of attacks against Canadians, both in Canada and Canadian Armed Forces members abroad," the document says.
A spokesperson for CSEC declined to comment about the lawsuit. In the past, the agency has limited its public comments to brief statements that simply point out it is illegal for CSEC to target Canadians.
Last August, Robert Decary, who at the time was CSEC's independent commissioner, delivered a report to Parliament that suggested ordinary Canadians may have been illegally spied on, but he complained that poor record keeping meant he couldn't be sure.
Decary also issued a public statement in June of last year that said CSEC's collection of metadata was within the law. Still, he said the commissioner's office was in the process of reviewing the practice to assess its impact on Canadians' privacy.
A spokesman for the current commissioner, Jean-Pierre Plouffe, declined to comment on the lawsuit but confirmed Plouffe is continuing to review the metadata program.
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