Previously, Harper has said nobody knew about the reimbursement scheme between Duffy and Nigel Wright, who resigned as the prime minister's chief of staff after the existence of the personal cheque was revealed.
Harper changed his tune Thursday, saying Wright "informed very few people" — all of them known to be key Harper confidantes.
"Mr. Speaker, I refer the prime minister to Hansard of June 5," said NDP Leader Tom Mulcair in question period on Thursday. "There was no 'very few' in there. It was 'nobody."'
On Friday, the Senate will resume debating motions to suspend Duffy, along with Senators Pamela Wallin and Patrick Brazeau, without pay or benefits for inappropriately claiming expenses.
The government leader in the Senate, Claude Carignan, said a day earlier that there would be no Conservative Senate caucus on Friday, and that the Senate will resume sitting at 9 a.m. ET. A vote on some motions is possible.
Duffy and Brazeau, along with retired Liberal senator Mac Harb, are under investigation by the RCMP for allegedly fraudulently claiming Senate housing allowances and living expenses.
The Mounties are also investigating the fact Duffy accepted $90,000 from Wright to help pay his expenses.
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