But Liberals want to go even further — getting auditor general Michael Ferguson to conduct an audit of Prime Minister Stephen Harper's office.
Liberal Senate Leader James Cowan says an audit of the PMO is needed to get to the bottom of the most explosive element in the Senate expenses scandal: the involvement of Harper's chief of staff, Nigel Wright.
Wright resigned last month after news broke that he had personally given $90,000 to Mike Duffy so the senator could reimburse improperly claimed expenses and housing allowances.
Marjory LeBreton, the government's Senate leader, says Cowan's motion to ask for an audit of the PMO is a "political stunt."
She says there's no role for the auditor general in examining the Wright-Duffy transaction because it did not involve any taxpayers' money.
"I would dare say that the RCMP, the two ethics officers, are the place for this to be handled," LeBreton said, referring to independent probes under way.
"My read of (Cowan's motion) is it's a political stunt and it really does not have anything to do with the resources of the Senate because no taxpayers' dollars were used."
CBC reported Thursday that a so-called secret Conservative party fund, controlled by the PMO, may have been used to reimburse Wright. But a party spokesman denied that.
"No party funds were used to reimburse anyone," said Fred DeLorey.
DeLorey said the fund is "not secret;" it's in the party's budget, receipts are issued whenever it's used and all party spending is ultimately accounted for in the Conservatives' annual financial reports to Elections Canada.
"A fund is maintained so that the party pays any party expenses — not taxpayers," he said.
LeBreton's own motion, calling on Ferguson to conduct a comprehensive audit of Senate expenses, was approved Thursday, with support from both Conservative and Liberal senators. The motion is broad, allowing Ferguson examine every expense claim by every senator, if he so chooses.
"I want the auditor general to come in here and feel absolutely free to go where he wants to go," LeBreton said.
Her motion is aimed at restoring public confidence in the Senate, which has been badly shaken over the last few months as allegations of improper expense claims have swirled around four senators: former Conservatives Duffy, Pamela Wallin and Patrick Brazeau and former Liberal Mac Harb.
Some senators, including some Conservatives, had raised concerns that calling in the auditor general would amount to an attack on the Senate's privilege to administer itself. But LeBreton scoffed at that.
"There's a school of thought in the Senate about parliamentary privilege and all of the niceties about the Senate being master of its own house. One of my colleagues in the back row was overheard to say, 'Tell that to the people I talk to in Tim Hortons on the weekend.'"
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