Emails in the Prime Minister's Office are at risk of disappearing forever, and need to be better monitored to prevent staff from improperly deleting them.

That's the conclusion of a 16-month probe by Canada's information commissioner, triggered by the temporary disappearance of emails crucial to the RCMP's criminal investigation of Senator Mike Duffy over inappropriate expenses and housing allowance claims.

"There was no evidence of [an] oversight mechanism in place to ensure that emails were being retained and saved as appropriate," says a report on the investigation.

"As such, it is possible for an employee to delete sensitive information, records with business value and other records that they feel are superfluous with or without intention."

Benjamin Perrin, a UBC law professor, was special adviser and legal counsel to the prime minister from 2012 to 2013. His lost-and-found emails, which were crucial to the RCMP's investigation into Senator Mike Duffy, triggered a probe by the information commissioner. (CBC) Information commissioner Suzanne Legault concludes that the Privy Council Office, Prime Minister Stephen Harper's own department, needs to regularly audit whether emails and other records are being erased improperly — and should make those audits public.

Almost 700 pages of heavily censored documents related to the probe were obtained by CBC News under the Access to Information Act. They provide an unprecedented peek at a key section of Legault's annual report to Parliament, which will be tabled this summer.

Her investigation was triggered in late 2013 by the sudden re-appearance of a series of sensitive emails by Benjamin Perrin, senior legal counsel to Harper, which the RCMP required as evidence for its probe of the Duffy affair.

Triggered by missing emails

Duffy was later charged with 31 offences, including fraud, breach of trust and bribery, in a case that involved Harper's inner circle, including Perrin and Nigel Wright, the prime minister's then chief of staff.

The Mounties had earlier been rebuffed by the Privy Council Office, which said all of Perrin's emails had been erased as a matter of course on his leaving the Prime Minister's Office in late March 2013. But the missing Perrin emails, in fact, had been preserved for potential use in an unrelated legal case, and were later turned over to the Mounties.

Perrin, who will be called as a witness in the Duffy trial later this year, is expected to be asked in court about the emails. The trial resumes Aug. 11.

The lost-and-found emails — and protocols that require bulk email deletions after just 30 days for all PMO and PCO staff — raised troubling questions about the permanent loss of historical records and of evidence needed for court cases. They also raised the prospect of politically embarrassing material disappearing with the tap of a delete button.

- Privy Council Office spokesperson

Liberal MP Ralph Goodale wrote to Legault on Dec. 3, 2013 — the same day she launched her investigation — asking her to examine "the capacity of PCO to maintain and retrieve records free from political interference."

Legault paid a Quebec-based accounting firm, Raymond Chabot Grant Thornton, almost $15,000 to do the heavy lifting in her review of PCO policies and protocols, though they did not examine actual practices.

The investigation concluded that on paper at least, the Privy Council Office has good record-retention policies, which also cover the Prime Minister's Office. But in practice there were nine areas of risk, including the lack of policing to ensure important emails were being preserved.

Federal policy says any record deemed to have "business value" must be preserved, whether it is an email, a text message, a BlackBerry pin-to-pin message or any other format. But the policy places the onus entirely on individual employees to determine whether there is "business value" and to archive the material appropriately.

Perrin, who said he was not contacted by Legault for her investigation, declined to answer questions about whether he archived his own emails as required, saying that his pending appearance as a witness at the Duffy trial prevented him from commenting.

Risks reduced by 2011 policies?

Goodale also said he had not been contacted by the information commissioner's office and was not aware of her conclusions. Legault's office said she could not comment or answer questions until her annual report is tabled this summer.

A spokeswoman for the Privy Council Office did not respond directly to a question about whether new safeguards — including regular audits — have been implemented as a result of Legault's report.

Liberal MP Ralph Goodale raised red flags in December 2013 about whether there was any political interference in email-retention practices in the Prime Minister's Office. (Susan Mas/CBC) "Both public servants and exempt staff [in the Prime Minister's Office] must archive information that has business value before they leave the department and that is made explicit in the departure process and documentation," Jacqueline Theoret said in an email.

"With the implementation of PCO's recordkeeping strategy [2011], the department has addressed the risk of inappropriate deletion of email and other records by implementing a comprehensive program of policies, tools, and training."

Legault's report is the second challenge of the Harper government this year over record preservation. She is currently in Ontario Superior Court fighting efforts to retroactively erase gun-registry data and to make gun-registry information immune to access-to-information requests.

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