Michael Doucet, executive director of the Security Intelligence Review Committee, says the watchdog will see a smaller slice of CSIS's activities in coming years.
Two bills before Parliament would reinforce the spy agency's long-standing ability to operate abroad and give it extensive new powers to disrupt security threats, rather than just gather information.
Doucet told the Senate national security committee that his agency's annual budget has essentially been flat over the last number of years at about $3 million.
He says the agency has enough resources to handle complaints about CSIS, certify the spy service's annual report to the public safety minister, and carry out seven or eight reviews of various issues.
However, Doucet wonders whether that will be sufficient to "cover the waterfront" of CSIS's activities as the spy agency does more.
"Is that enough in the future given the complexity of the service's operations, is the question that we would have to ask ourselves," he told the senators Monday.
"I would say we would be seeing over time a smaller slice of their activities on a yearly basis."
The amount of discretionary funding to do new things is "diminishing in size," Doucet said.
For instance, the review committee examines one of CSIS's foreign posts a year, but would not have the money to visit two, he said.
The government has consistently praised the review committee as providing robust scrutiny of CSIS.
However, Doucet's comments come amid concerns — voiced by many critics of the government's proposed anti-terrorism measures — that existing review and oversight are inadequate to properly monitor the intelligence activities of CSIS and other security agencies.
The legislation would give CSIS the ability to actively thwart terror plots, make it easier for police to limit the movements of a suspected extremist, expand no-fly list powers, crack down on terrorist propaganda, and remove barriers to sharing security-related information.
Canada’s real-time oversight of spy agencies is "imperfect" and its after-the-fact review of security activities is perhaps "close to broken," law professors Craig Forcese and Kent Roach said in a recently published analysis.
The "poorly constructed" anti-terrorism bill introduced last month will only make things worse because it expands spying and information-sharing powers, they added.
Doucet said Monday the review committee cannot pursue an investigation beyond CSIS to other agencies because the committee's mandate does not permit it.
"We feel encumbered by the fact that, as information is passing, and continues to pass amongst organizations, we cannot see that thread through to other organizations."
Expansion of the review committee's reach could be accomplished through legislative change, Doucet told the senators.
"That would probably be a good way to do it."
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