MPs are heading home for their extended holiday break, but the New Democrats and Liberals aren't done talking about an ongoing scandal involving Senator Mike Duffy's expenses and a cheque from Prime Minister Stephen Harper's former top adviser.

The opposition party caucuses gathered Wednesday morning, while the Conservatives seemed to eschew their weekly meeting, after the House agreed Tuesday night to break for the holidays.

Liberal Leader Justin Trudeau said Canadians are cynical about politics, especially following the last several weeks.

"Canadians have enormous reason to be cynical," Trudeau said.

"I've also seen that Canadians are tired of being cynical. They want another option."

Trudeau said the government may hope the Senate scandal will fade away over the six-week break MPs have, but he doesn't expect that will happen.

"They certainly hoped it would fade away over the summer as well," he said.

PM 'isn't capable of telling the truth'

New Democrats have criticized Harper for regularly missing question period as NDP Leader Tom Mulcair fires questions about Harper's parliamentary secretary. But Trudeau hasn't been in the House every day either.

Asked about his regular absences from the House, Trudeau said people want to see him in their communities, meeting with them.

"I do everything from meeting with community groups, to business leaders, holding volunteer rallies where people come together to talk about politics and issues and hear my vision for the future. It’s about drawing people into a political process that has honestly left them to the side," he said.

Trudeau usually attends question period one or two days of the five days a week it's held.

New Democrat MP Alexandre Boulerice said Canadians will take away from this session that it's hard to tell whether Harper is telling the truth.

"There are plenty of versions of the same story, he isn't capable of telling the truth to people," Boulerice said of Harper, in a scrum on Parliament Hill after his party's meeting.

"We question seriously whether the prime minister is telling the truth ... I think the RCMP will continue to do their work."

Affidavits filed in an Ottawa court show the RCMP are investigating Duffy and Nigel Wright, Harper's former chief of staff, for fraud, bribery and breach of trust. No charges have been laid and the allegations haven't been tested in court.

MPs will return to their ridings for the next six weeks, with the House expected to return on Jan. 27.

Senators usually rise a few days after the House.