In a submission to the House of Commons public safety committee, Daniel Therrien says measures in the bill to guard against unreasonable loss of privacy are "seriously deficient."
In their own brief to the committee studying the bill, Therrien's provincial and territorial counterparts say the provisions significantly expand government powers to monitor and profile ordinary, law-abiding Canadians.
"Such a state of affairs would be inconsistent with the rule of law in our democratic state and contrary to the expectations of Canadians," they say.
The federal government brought in the bill — which would significantly expand the Canadian Security Intelligence Service's mandate — following the daylight murders of two soldiers last October.
The legislation would give CSIS the ability to disrupt terror plots, make it easier to limit the movements of a suspect, expand no-fly list powers and crack down on terrorist propaganda.
It would also remove many barriers to sharing security-related information, raising grave concerns on the part of the privacy commissioners.
Therrien says the bill could make available all federally held information about someone of interest to as many as 17 government departments and agencies with responsibilities for national security.
The legislation sets the threshold for sharing Canadians' personal data far too low, he says.
In addition, Therrien is concerned the bill sets no clear limits on how long the information would be kept.
"While the potential to know virtually everything about everyone may well identify some new threats, the loss of privacy is clearly excessive," Therrien's brief says.
"All Canadians would be caught in this web."
For instance, in an effort to identify people who may have become foreign fighters abroad, the Canada Border Services Agency could be asked to provide information on all individuals, including tourists and business people, who have travelled to countries suspected of being transit points to conflict areas, Therrien says.
The privacy commissioner published his submission to the committee Friday in advance of hearings slated to begin next week. MPs plan to hear from more than 50 witnesses.
Opposition MPs have repeatedly criticized the government for boosting security powers in the legislation but not giving watchdogs more bite.
Fourteen of the 17 agencies empowered to receive security information under the bill have no dedicated watchdog looking over their shoulders, Therrien said in an interview. "So I think the problems we have with review currently are exacerbated by the bill."
Therrien said while he can look into complaints about information exchanges, all he can do is make recommendations to the government if he finds a practice to be unauthorized or illegal.
Canadians would not be able to ask a court to review the information-sharing made possible by the bill, he added. "There is no judicial review of these activities and I think that is something that is clearly a flaw in the system."
Therrien recommends allowing information to be shared only out of necessity, not because it is merely relevant to an agency's interest.
He also urges a second look at the notion of sharing related to "activities that undermine the security of Canada" to ensure the wording captures only real security threats.
In their letter to the committee, the provincial and territorial privacy commissioners say the Harper government has yet to produce evidence the new information-sharing measures are needed.
They call on Ottawa to withdraw the bill or, failing that, make amendments to ensure new powers are limited and protect Canadians' constitutional rights and freedoms.
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