The allegations are spelled out by investigators in documents authorizing a production order — a binding court document aimed at compelling the Senate and its auditors to hand over material related to the police investigation.
In particular, the Mounties have asked for several versions of Wallin's electronic Senate calendar, saying the calendars could provide further evidence to back up the allegations.
Wallin has not been charged with an offence, nor have the allegations been proven in court.
The investigation and subsequent allegations relate to a Deloitte audit that flagged more than $140,000 in questionable travel expenses Wallin claimed between Jan. 1, 2009, and Sept. 30, 2012 — expenses she has since paid back.
In the court filings, RCMP Const. Michael Johnson said there are reasonable grounds to believe that two offences have been committed.
The documents allege Wallin "did commit breach of trust in connection with the duties of office" and "by deceit, falsehood or other fraudulent means defrauded the Senate of Canada of money by filing inappropriate expense claims," contrary to the Criminal Code.
In addition to the calendars, the police also want to see all of Wallin's travel expense claims between Jan. 9 and Sept. 30 this year.
They're also requesting billing statements from her corporate and personal credit cards, statements for her Senate-supplied cell phones and all recordings and notes from Deloitte interviews conducted during their audit.
The latest twist comes with the Senate mired in a politically explosive debate about whether Wallin and fellow former Conservative senators Mike Duffy and Patrick Brazeau should be suspended without pay over their disallowed expense claims.
In his request for a production order, Johnson points to several instances where Wallin submitted expense claims for travel to events in Toronto. But many of the timelines included in her electronic calendar submissions don't add up, he alleges.
Accounting firm Deloitte, hired to review Wallin's expense claims, noted that there were three versions of her calendar, and that entries had been altered more than 391 times.
After reviewing the Deloitte audit findings, Johnson told the court that Wallin spent most of her time in Toronto, despite declaring Wadena, Sask., as her "primary residence."
One travel claim highlighted in the documents showed her flying from Ottawa to Toronto on June 4, 2009, for "Senate business." Wallin later told investigators the flight was to attend the Institute of Corporate Directors Fellowship Awards.
But the awards gala was scheduled to start at 5:30 p.m. that day. Wallin's flight didn't arrive in Toronto until 9:05 p.m. Investigators also found, as part of Wallin's travel claim, a car service invoice indicating the senator was driven that day from "airport to home."
Wallin — who initially described the Deloitte audit as "fundamentally flawed and unfair" — has accused some fellow senators of succumbing to a "lynch mob'' mentality in trying to suspend her.
In her Oct. 23 speech to the Senate, Wallin admitted to having made mistakes in her expenses filings. "When we found mistakes, we acknowledged them and I repaid the amounts immediately," she said.
She also said she co-operated fully with the outside auditors.
"My assistant and I worked night and day verifying timelines, searching out supporting documentation for each and every event — and there were many."
Wallin said the whole proceeding against her, including the bid to suspend her, is a result of backroom politics. "It is, as my lawyer said, Kafkaesque."
The independent audit cleared her name, she insisted, but the attacks carried on.
"Just to be clear, when asked, Deloitte said there was no evidence of deliberate misrepresentation or fraud or fiddling with the books, as the media had reported," she said.
"They spoke with former staff members who agreed, and by their own admission, Deloitte conceded they had no standard by which to judge my activities."
The latest batch of documents shows investigators interviewed Marjory LeBreton, the former leader of the government in the Senate, in late September.
During the interview, LeBreton told investigators that she felt Wallin "has a sense of entitlement," but that she didn't believe that Wallin tried to scam the system or that she had committed any criminal offence.
A month after the interview, Wallin stood in the Senate and accused LeBreton _ and fellow Conservative Carolyn Stewart Olsen _ of resenting her for being "an activist senator."
Investigators also questioned the Senate's director of finance, Nicole Proulx.
She told them that concerns about Wallin's expense claims had been raised as early as 2009, and that she and Senate clerk Gary O'Brien had spoken with Wallin about the claims on several occasions.
A more "serious" discussion with Wallin took place in January 2012, where Proulx and O'Brien warned her about complying with Senate policy, the documents say.
One incident highlighted in the documents was a travel expense claim submitted by Wallin for travel to Trenton, Ont., on April 30, 2011, where she was to participate as a member of a political panel to comment on election results.
But a subsequent audit by Deloitte found the event was actually a Conservative party rally, and the expense was deemed by Proulx as "not legitimate."
The documents also show Proulx told investigators that several expense claims submitted by Wallin for car service were rejected in 2010 by Senate Finance — but that the decision was reversed by the Senate's board of internal economy after Wallin complained.
The court filings also spell out in detail the Senate's rules for filing expense claims.
One section cited stipulates that senators may not claim reimbursement for expenses related to their private business dealings, or for participating in partisan political party activities or fundraising events, other than those organized by the Senate.
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