Andrew Scheer, the Speaker of the House of Commons, last week offered the use of House administration resources as well as "external experts" to help resolve the complaints against Massimo Pacetti and Scott Andrews, both of whom insist they've done nothing wrong.
The NDP dismissed his offer last week and insisted neither of the two New Democrat complainants wanted to pursue the matter.
However, one of the women, who began late Monday to disclose details of her complaint in media interviews, has said she'd be willing to take part in an investigative process.
The party is now asking Scheer to provide more detail about the process he's offered.
"The real question is going to be, you're going to have to tell me what that process is," NDP Leader Tom Mulcair said Wednesday.
"That's why (NDP whip) Nycole Turmel wrote a very detailed letter yesterday to Speaker Scheer saying, 'What are you talking about here because we're not sure whether it's prospective, retrospective, what it would apply to.' You can't mediate something like this, obviously, so what exactly is on the table?"
Mulcair urged other leaders to endorse his proposal to develop a formal code of conduct for MPs and appoint a non-partisan officer of Parliament to investigate complaints.
"Instead of passing this back and forth like a hot potato, take the concrete proposal that's on the table, sit down together and start trying to come up with a solution to deal with this," Mulcair said.
The NDP leader has had no response from Prime Minister Stephen Harper or Liberal Leader Justin Trudeau since making his proposal two weeks ago, he added.
Last week, Turmel said Mulcair's proposal was intended only for complaints that may arise in future, not to the complaints that have sparked a frenzy on Parliament Hill since Trudeau abruptly suspended Pacetti and Andrews over what he called "serious personal misconduct."
But Mulcair said Wednesday he sees his proposal as a "starting point" for creating a process to deal with the current situation and added that he's open to other suggestions from other leaders.
"I'm not claiming to have tranquil possession of the truth on this. I want to make sure that we get a result. That's the obligation."
Trudeau welcomed the NDP's apparent change of heart.
"We have said from the very beginning that we believe that the Speaker's office is the best place to launch an independent, confidential, third party process in this situation," he said.
"I'm glad it looks like we're going to be able to embark upon a rigorous third party process."
Such a process is important, he said, both to give the suspended Liberal MPs "an opportunity to tell their sides of the stories" and to reassure and encourage complainants in future to come forward with allegations, knowing that their complaints will be taken seriously.
"What this entire situation over the past weeks has demonstrated is the lack of process on Parliament Hill is a situation we cannot endure," Trudeau said.
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