In a sworn affidavit filed in an Ontario court, RCMP Cpl. Greg Horton said the force wants to see records dating back to the time Harb was appointed to the upper chamber a decade ago by former prime minister Jean Chretien.
"The period of time for which I am seeking documents and data is for the entire time that he has been in the Senate for which records are available," Horton wrote in a document known as a production order.
He said the Senate has indicated it routinely holds on to records for eight fiscal years, and those reports are readily available. However, the deputy law clerk in the Senate has indicated copies going back even further might be around.
"I believe that an analysis and audit of these records and expenses will provide evidence of the named offense by demonstrating that Harb's primary residence is in Ottawa," Horton wrote.
"They will also provide a record of all inappropriate housing expenses claimed by Harb, and assist in advancing the investigation."
A separate Senate committee investigation, looking at the immediately available records, estimated that Harb inappropriately claimed up to $231,649 between 2005 and 2012 — a figure the senator disputes.
The Mounties are investigating Harb for breach of trust, and probing back before 2005 could push that figure higher.
None of the allegations have been proven in court.
The Senate's board of internal economy only ordered him to repay $51,482 in living expenses associated with the inappropriate housing claims. He is also fighting the repayment order in court.
The Senate has indicated it will cooperate with the RCMP request for more information.
The Mounties say they don't believe the senator has lived anywhere outside of Ottawa, and have already uncovered property tax records that show the properties Harb, a former Ottawa MP and local city councillor, has owned in the city.
The documents say he owned two other residences outside of Ottawa which he claimed at various times as primary homes.
When it came time to sell one of the properties, neighbours interviewed as part of the investigation reported Harb telling them his family didn't "want to live there."
The affidavit claims the senator bought a rundown property in Cobden, Ont., outside of Ottawa, in September 2003, roughly three months after he was appointed to the Senate.
Horton said Harb never lived in the home and that it "was largely uninhabitable for the first three years that he owned it, due to demolition and reconstruction.’’
The purchase of the home, just outside of the 100 kilometres allowed for under Senate expense rules, gave him the ability to claim as much as $22,000 a year in expenses by claiming it as his primary residence.
The affidavit states that in October 2007 Harb sold 99.99 per cent of the ownership of the Cobden home to Magdalene Teo, who was at the time the Brunei high commissioner to Canada.
Despite almost entirely divesting himself of the property, Harb used his 0.01 per cent of the stake to continue to claim it as his primary residence.
That changed in 2011 when he bought another home in near Westmeath, Ont., which he then claimed as a primary residence.
The RCMP is also looking into the expenses of former Conservative senators Mike Duffy and Patrick Brazeau.
It is investigating the $90,000 bailout of Duffy by Nigel Wright, the prime minister's former chief of staff.
Harb's office has not responded to requests for comment.
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