"At this point, we have not been invited," a spokeswoman for Privacy Commissioner Daniel Therrien told CBC News on Wednesday.
"The commissioner has said that, given the significant implications for privacy, he would welcome an opportunity to appear to discuss his submission in more detail with committee members," Valerie Lawton added.
"He remains hopeful that the committee will be able to hear from him."
It's not clear precisely how Therrien ended up not making it onto the final witness list, as the selection process takes place behind closed doors.
But his name was near the top of the proposed witness lists provided to CBC News by the New Democrats and the Liberals.
Tories block bid to add Therrien
During Tuesday's meeting, New Democrat MP Randall Garrison attempted to get unanimous consent for a motion to add a one-hour session with Therrien to the meeting schedule, but was rebuffed by the Conservatives.
But Public Safety Minister Steven Blaney stated, in response to a question, that his office had "consulted" with the commissioner on the bill, and added that he intends to meet with Therrien.
"As you know, this bill is about the protection of the rights and freedoms of Canadians and their privacy," he noted.
"There are embedded mechanisms in Bill C-51 and already within government, such as the privacy impact assessment, that will apply to the measures planned in this bill."
In the meantime, committee members will, however, be able to peruse the written commentary submitted by Therrien last week, in which he delivers a starkly worded warning on the implications for privacy rights:
"While the potential to know virtually everything about everyone may well identify some new threats, the loss of privacy is clearly excessive," he writes.
"All Canadians would be caught in this web."
In his submission, Therrien explains how the bill could give as many as 17 federal departments and agencies access to every bit of data, personal and otherwise, that any department might hold on Canadians.
Language 'extremely broad', watchdog warns
The language used to establish those new powers is "extremely broad," he notes before offering several examples of how the new provisions could affect all Canadians, not just those suspected of harbouring terrorist ambitions, or even sympathies.
"For instance, all the tax information held by the Canada Revenue Agency, which historically has been highly protected information, would be broadly available if deemed relevant to the detection of new security threats," he warns.
"As well, all information that departments hold about young persons that was obtained for a specific purpose could be further shared with these 17 departments and data mined with a view to identifying those at risk of being radicalized. "
And the Canada Border Services Agency "could be asked to provide information on all individuals, including tourists and business persons, who have travelled to countries that are suspected of being transit points to conflict areas."
'Virtually limitless powers … to profile ordinary Canadians'
The result, he says, would be to give the 17 government institutions currently involved in national security "virtually limitless powers to monitor and, with the assistance of Big Data analytics, to profile ordinary Canadians, with a view to identifying security threats among them."
The submission includes several recommended amendments, including raising the threshold required to trigger the new sharing powers, imposing strict new retention limits on the data.
Therrien also adds his voice to the chorus calling for a more vigorous oversight regime, and backs the idea of giving parliamentarians a central role in ensuring "independent and effective review."
While Therrien may not have made the short list, it's likely that at least some of his concerns will be put forward by other witnesses.
"[We] will definitely be raising privacy issues, including some of the same ones raised by the current privacy commissioner, as well as previous ones," Paul Champ told CBC News.
He's slated to appear before the committee on behalf of the International Civil Liberties Monitoring Group Thursday morning.
Other scheduled witnesses include Assembly of First Nations Grand Chief Perry Bellegarde, professors Craig Forcese and Kent Roach and former Progressive Conservative MP and one-time employment minister Ron Atkey, who was the first-ever chair of the Security Information Review Committee.
On Tuesday, the committee heard from Blaney and Justice Minister Peter MacKay, as well as RCMP Commissioner Bob Paulson and CSIS head Michael Coulombe.
The full witness schedule for Thursday:
Morning session (8:45-10:45 a..m. ET)
British Columbia Civil Liberties Association counsel Carmen Cheung
Greenpeace Canada executive director Joanna Kerr and energy campaign head Keith Stewart
Former Security Information Review Committee (SIRC) chair Ron Atkey
Assembly of First Nations National Chief Perry Bellegarde
International Civil Liberties Monitoring Group lawyer Paul Champ
University of Calgary political science professor Barry Cooper
Evening session (6:30-8:30 p.m. ET)
National Airlines Council of Canada executive director Marc-Andre O'Rourke
University of Ottawa professor Craig Forcese and University of Toronto professor Kent Roach
National Council of Muslims executive director Ihsaan Gardee
Amnesty International Canada secretary general Alex Neve
Carleton University professor Elliot Tepper
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