The suspension of three former Conservative senators without pay did not stop the opposition parties from keeping up their attacks on Stephen Harper over what his office knew about a plan to repay the inappropriate expenses of senator Mike Duffy.

Both the Official Opposition New Democrats and the Liberals asked Stephen Harper, during question period on Wednesday, whether key Conservatives had any role in his former chief of staff's decision to repay Duffy's $90,000 in ineligible expenses from his own pocket. Nigel Wright later arranged for the party to pay the embattled senator's legal fees.

"Was Jenni Byrne [political director of the Conservative Party] aware of the plan to repay Mike Duffy's expenses using Conservative Party funds? Yes or no?" Mulcair asked Harper.

Byrne, whom Mulcair noted has a fearsome reputation, currently works as the deputy chief of staff to the prime minister.

"Without proof, the leader of the NDP is making allegations against people. Clearly Mr. Wright acted alone and accepted responsibility for that," Harper responded.

This is government business. This is the public's business. - Tom Mulcair, NDP leader

In a surprising move, House of Commons Speaker Andrew Scheer intervened on more than one occasion to warn Mulcair to stick to government business, not party business.

"As I heard it, it seemed mostly to deal with party business but I'll let the Right Honourable Prime Minister answer," Scheer told the Commons.

The prime minister reiterated that Wright has taken responsibility for his actions and was held accountable.

The leader of the NDP hit back at the Speaker saying, "Just to be clear, perfectly clear, this is about a coverup in the Prime Minister's Office. This is government business. This is the public's business."

NDP MPs erupted in cheers before Mulcair pressed on with another question to Harper.

Mulcair said Wright told the RCMP that Irving Gerstein, a Conservative senator and chief fundraiser for the party, approved the original plan to pay back Duffy's ineligible expenses using party money.

But Gerstein dismissed Wright's version of events during a speech to the party faithful in Calgary last weekend.

"Both can't be true. Did Senator Gerstein lie to Conservative Party members?" Mulcair asked Harper.

Mr. Wright has been very clear on who he brought into his confidence on this matter. - Paul Calandra, parliamentary secretary to the prime minister

The prime minister did not answer the question directly saying only that Wright made the decision to repay Duffy's ineligible expenses."That's a decision he took himself," Harper said.

Liberal MP Geoff Regan asked the government whether Chris Woodcock, former director of issues management​ for Harper, had been contacted by the RCMP.

Woodcock went from working in the Prime Minister's Office to currently serving as chief of staff to Natural Resources Minister Joe Oliver.

Paul Calandra, Harper's parliamentary secretary, did not directly answer the question saying the Prime Minister's Office will continue to co-operate with authorities.

Calandra added that "Mr. Wright has been very clear on who he brought into his confidence on this matter."

Wright told the RCMP, according to court documents filed in July, that he told four people in Harper's office that he was going to write Duffy a cheque: Irving Gerstein, David van Hemmen, Benjamin Perrin, and Chris Woodcock.

On Tuesday, Harper told the Commons his office was not under investigation by the RCMP.

However, in an email to CBC News after question period, a spokesperson for the prime minister confirmed police have asked the Prime Minister's Office for documents and the PMO has provided them.​

"Yes. We have actively assisted them," Jason MacDonald, the director of communications for Harper said.​

Mulcair dismisses suspension pension question

Earlier in the day, Mulcair said he couldn't care less whether three suspended senators will receive pensions at the end of their suspensions, the Opposition New Democrats will continue to push for Senate abolition.

"Do you honestly think I care about a detail as to whether or not one of them gets their medical benefit here, or their pension there," Mulcair said.

"You're asking me to comment on the flowers in the tapestry," Mulcair said when asked to comment on the lack of clarity around the impact of Tuesday's suspensions.​

"Why stop at three? Let's get rid of all of them," Mulcair said. "I couldn't care less about their pension, I want to get rid of them."

The Liberal leader could not say whether the senators' suspension ought to count as pensionable service saying only that "this government has not thought through all the consequences around this suspension."

Trudeau said it was a question for the government and the Senate.​

The Senate voted Tuesday night to suspend senators Patrick Brazeau, Mike Duffy and Pamela Wallin for inappropriate expense claims.

Trudeau calls on PM to testify under oath

Mulcair took a swipe at Liberal Leader Justin Trudeau for advising Liberal senators to abstain from voting during Tuesday's key vote in the Senate saying "he doesn't understand ethics."

"For Justin Trudeau to say his senators should abstain on the most profound issue of corruption in Canadian politics since the Liberal sponsorship scandal shows just the extent to which Justin Trudeau doesn't understand these issues.

" And that's a scandal in and of itself," Mulcair said.

Trudeau told reporters after his party's weekly caucus meeting that he felt it was important for him to give Liberal senators his opinion on the matter.

"What the three senators in question did was wrong and we shouldn't be defending them. But at the same time, what Mr. Harper has done is wrong in trying to cover up and hide, and avoid actual accountability on this issue.

"So I felt that a strong option, that I was recommending to all senators, was to abstain from voting," Trudeau said.

The Liberal leader said he continues to be in favour of Senate reform as long as it does not involve reopening the constitution. Asked how that would work, Trudeau said he was exploring different options.

The Liberal leader called on Conservative MPs to vote later today in favour of a Liberal motion that would see Harper testify under oath before an ethics Commons committee about the Senate expenses scandal.

While the three suspended senators will continue to receive benefits without pay or access to office space or staff, it is not yet clear what will happen to their pensions. The suspensions are expected to last until the current session of Parliament ends.

All three senators are under investigation by the RCMP over questionable expense claims.

No charges have been laid.