Two years ago, when the Liberals were on their apparent death bed, Mulcair categorically ruled out a coalition.
Mulcair said then that the Liberals had walked away from a 2008 agreement to form a coalition government with the NDP, proving they couldn't be trusted. He insisted that he would never try working with them again, either formally or informally.
"N.O.," he said in an interview with Huffington Post Canada.
"The no is categorical, absolute, irrefutable and non-negotiable. It's no. End of story. Full stop."
Mulcair was a leadership candidate at the time and the NDP, still pumped from their historic second-place finish in the 2011 election, was well ahead of the decimated Liberals in the polls.
Since Justin Trudeau took the helm of the Liberals last April, the Grits have staged a comeback, enjoying a comfortable lead in the polls while the NDP has sunk back into third.
On Wednesday, Mulcair suggested his 2012 comments were intended to indicate only that he wouldn't agree to any form of electoral co-operation with the Liberals during an election — a position that he stressed remains unchanged.
But he repeatedly refused to say whether he'd be willing to form a coalition with the Liberals after an election, if that's what it took to replace Prime Minister Stephen Harper's Conservative government.
"Canadians decide the type of Parliament that they're going to give themselves and we've proven over the years that we're always open to working with the others," the NDP leader said after a caucus meeting.
"We're a progressive party. My priority is to get rid of Stephen Harper's Conservatives. That's my priority."
Reminded of his categorical rejection of a coalition two years ago, Mulcair said: "Yes, exactly.
"So, nothing's changed. They're two different questions. What will we do after an election when an NDP government is formed? We're going to work with others. And what will we do to get there? We're going to run (a full slate of) 338 candidates."
If, as Mulcair now insists, his 2012 comments were intended to reject only electoral co-operation during an election, it's not clear why at the time he referenced the 2008 coalition agreement as proof that the Liberals can't be trusted.
The 2008 agreement was struck shortly after an election, not before or during the campaign.
In any event, Mulcair's perspective on the 2008 agreement seems to have changed as well. He cited it Wednesday as an example of how the NDP is willing to work with other parties and will continue doing so.
"I was part of the team that actually fashioned a formal agreement on that with the Liberals because our priority in '08 in the wake of the economic crisis was to get rid of the Conservatives whom we simply didn't trust to be able to do what was necessary with the economy to save people," he said.
"So, I think we did the right thing and we showed our willingness to work with others. That's a history that we have in the NDP. That's what we're going to continue with."
For his part, Trudeau repeated his stance that he's "not going to entertain any discussions around coalition."
He argued that there are "significant, substantive disagreements on very serious matters of policy" between the Liberals and NDP. He cited as examples the NDP's position that a bare majority Yes vote should be sufficient to trigger negotiations on Quebec's secession and its willingness to reopen the Constitution to abolish the Senate.
Still, he added that the Liberals are "always extremely open to working with all MPs in the House of Commons, whatever their partisan allegiance," in order to pass legislation that will benefit Canadians.
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