The Senate’s internal economy committee sanitized the original audit of Sen. Mike Duffy’s expenses to remove damning findings, documents obtained by CTV News show.

A confidential report obtained by CTV’s Ottawa Bureau Chief Robert Fife shows the original version of Duffy’s audit found that the senator broke the Senate’s “very clear” and “unambiguous” residency rules.

The report found that Duffy stayed in his Prince Edward Island cottage mostly during the summer months. He had listed it as his primary residence, which allowed him to claim an annual housing allowance given to senators who live more than 100 kilometres from Ottawa.

Duffy’s air travel pattern also showed he lived in Ottawa and he had registered his address in the capital “for several official purposes,” according to the original report.

The report also reveals that Duffy’s lawyers sought to have him exempted from the forensic audit.

All of that was missing from the rewritten audit report that was tabled in the Senate and made public.

Sources say the whitewash was part of a backroom deal with Prime Minister Stephen Harper’s chief of staff, Nigel Wright.

Fife revealed earlier this week that Wright helped Duffy pay back a $90,172 debt to the Senate for improperly claimed living expenses.

The PMO then confirmed that Wright, a former Bay Street executive, wrote a personal cheque to Duffy as a gift to an old friend, although sources say the two men are not close.

The night before, the senator claimed in an email to CTV News that Wright played no role and that he’d taken out a loan to repay the money.

Duffy quit the Conservative caucus Thursday as questions swirled over whether the $90,000 cheque from Wright violated ethics rules that prohibit senators from accepting gifts. Under the Senate Conflict of Interest Code, all gifts over $500 must be reported within 30 days.

“We need to know what were the terms and conditions. What’s the quid pro quo here for $90,000?” Liberal MP Ralph Goodale said. “What was Senator Duffy expected to do?”

Meanwhile, the Senate’s internal economy committee wants to have another look at Duffy’s expense claims amid growing questions about his conduct, including new revelations that he filed claims for Senate business while campaigning for the Conservatives in the last federal election.

Documents revealed that Duffy billed taxpayers for being on official Senate business while he was campaigning for the Conservatives during the 2011 federal election. If it is confirmed that Duffy attended eight campaign events and submitted Senate expenses, he could be in trouble for double-billing.

The Conservative Party told CTV News on Thursday that it paid for all of Duffy’s campaign expenses. But social media and newspaper reports show that Duffy’s reported Senate business overlapped with campaign events he attended.

A Senate source, who spoke on condition of anonymity, told The Canadian Press Friday that given the new accusations, senators want Duffy’s expense reports to be sent back to the committee for further review.

Also on Friday, the NDP asked Elections Commissioner Yves Cote to look into the issue of possible double-billing by Duffy.

In a letter to the elections commissioner, NDP MP Craig Scott said his party is also “concerned by evidence that these types of ‘expense sharing’ arrangements may not have been limited to Senator Duffy,” as other senators also campaigned during the 2011 federal election, including Pamela Wallin, Dennis Patterson, Nancy Greene-Raine, David Smith and Grant Mitchell.

Duffy is one of three senators whose expense claims came under scrutiny over allegations they were improperly claiming tens of thousands of dollars in living expenses.

Independent audits released last week found that Duffy, Sen. Patrick Brazeau and Sen. Mac Harb spend more time in Ottawa than the homes they claimed were their primary residences, rendering their claims ineligible.

The Senate’s internal economy committee ordered Brazeau to repay about $48,000 and Harb $51,000. Duffy repaid the expenses in March, before the audits were released.

Although Duffy said Thursday that it was his decision to step aside and sit in the Senate as an independent, a senior official told Fife that the senator was pushed out of caucus because of the growing questions surrounding his conduct.

Andrew MacDougall, spokesperson for the prime minister, says Harper has full confidence in Nigel Wright, and he will remain on the job.

On Wednesday, Canada’s ethics commissioner, Mary Dawson, said she will investigate Wright’s cheque to Duffy.

MacDougall said the Prime Minister’s Office is fully co-operating with her probe.

With files from The Canadian Press