The procedural manoeuvre may also have the added political benefit of papering over the rift that's erupted in Conservative ranks over the proposed suspensions of the trio, making it harder for Tory senators to vote against the government.
It was unveiled Wednesday, moments after Senate Speaker Noel Kinsella ruled out of order the government's attempt to limit debate on three separate motions to suspend, without pay, senators Mike Duffy, Pamela Wallin and Patrick Brazeau.
The motions had been introduced two weeks ago by government Senate leader Claude Carignan as non-government business and have been preoccupying the upper house ever since.
Debate has been punctuated by two explosive interventions from Duffy, who accused the Prime Minister's Office of orchestrating a secret deal to reimburse his allegedly invalid expense claims and coaching him to lie about it.
Kinsella ruled Wednesday that closure can only be imposed on debate over government business.
Carignan immediately served notice that he'll replace the three non-government motions with a single government motion to suspend the trio.
The new motion softens the proposed sanctions somewhat: the three would still be stripped of their paycheques, Senate resources and privileges but would be allowed to retain their Senate life insurance, prescription drug and dental benefits.
Carignan's office would not comment on its anticipated timetable for the new motion. Carignan said a vote could come as early as Thursday while some Conservative senators said they don't expect a vote before next week.
But Liberal senators had little doubt the PMO was pulling the strings to ensure the long, drawn-out, damaging debate is over by the time Harper is scheduled to give the keynote speech Friday evening at the Conservative party's national convention in Calgary.
As government business, Carignan could technically introduce a closure motion Thursday after brief debate on the new motion, according to Liberal Senate officials. The closure motion would require six hours of debate on Friday, after which a vote could be called late that afternoon.
The problem with Carignan's original approach arose when the debate didn't proceed fast enough to suit Harper's political agenda, asserted Liberal Sen. David Smith.
"Everybody wasn't just saying, 'Hail Mary,' and moving with holy haste so Harper could nail the lid on three motions with great big spikes before Calgary."
Carignan said the vote, whenever it comes, will be a "totally free vote" for Conservative senators.
But Sen. Hugh Segal, who has led the dissident Conservative charge against the suspension motions, said the fact that the suspensions are now a matter of government business will make it harder for him to vote his conscience.
"I have to assess what I'm going to do between now and then. As a general principle, I've never voted against a government motion," he said.
While he lauded the government's willingness to let the three senators keep some benefits as a "touch of humanity," Segal said it doesn't change his belief that the proposed suspensions amount to sentencing the trio before they're charged, given a fair trial or convicted of any wrongdoing.
A grim-faced Sen. Don Plett, a former Conservative party president who has also spoken out against the suspensions, marched past reporters.
"Well, I've had happier weeks," he said through gritted teeth.
Later, Plett said his views on the proposed suspensions have changed "somewhat" now that they are part of a government motion.
There was evidence, however, that the prolonged debate has already taken its toll on Conservative solidarity.
At one point Wednesday, Tory Sen. Nicole Eaton emerged from the chamber as Segal was speaking at length with reporters. Seeing the scrum, she visibly rolled her eyes and was overheard to mutter: "Oh, shut up."
Later in the day, Segal was the only Conservative senator to support a Liberal bid to defer a decision on the proposed suspensions until the trio are given a fair hearing before a Senate committee. Wallin also supported the idea, while Brazeau and Duffy were not in the chamber.
"I have been absolutely consistent. I would like a fair hearing," Wallin said after the Liberal proposal was defeated.
In the House of Commons, meanwhile, opposition parties continued to grill Harper over Duffy's latest revelation, that the Conservative party paid his $13,500 legal fees. That's on top of the well-known $90,000 Harper's former chief of staff, Nigel Wright, gave Duffy to reimburse the Senate for his expenses.
"If, as the prime minister says, he does not defend the actions of Mr. Duffy, why then is he literally paying to defend the actions of Mr. Duffy?" questioned NDP Leader Tom Mulcair.
Harper continued to insist it's routine for all political parties to pay legal expenses for its caucus members. And he tried to turn the tables, dredging up an eight-year old defamation suit which Mulcair lost, leaving his party at the time — the Quebec Liberals — to pay the $95,000 in damages.
"I wonder how many members of the NDP are aware that this party leader not only claims expenses for court cases he loses but also expects his political party to actually pay for him the damages imposed by a court of law?" said Harper.
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