The crisis over the speakership plunges the Gillard government into another period of uncertainty.
No one is sure how Peter Slipper will vote, as he returns to being a humble backbencher, an independent. He does not have the power to bring down the government, nor would he be inclined to, as it would bring his career to a quick end.
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Slipper announces resignation
Peter Slipper tells the House of Representatives he will tender his resignation as Speaker to the Governor-General.
The Liberal National Party formally disendorsed him, and criticised him harshly, meaning he might lean towards Labor.
A government frontbencher said last night Slipper would consider his vote on every issue but predicted the former Speaker would be disinclined to vote with the opposition after all the Queensland Liberal National Party had done to him.
Falling on his sword last night was the only viable course open to Slipper, after the publication of his vile text messages. The parliamentary debate confirmed his position was untenable.
Earlier the government rejected claims it was being hypocritical when it voted for him to remain as Speaker.
Labor relied on allowing due process to occur in the courts as its reason to defer action, while at the same time making clear his comments were offensive.
Even the Prime Minister's stellar performance in Parliament did not overcome the glaring reality that the position of Slipper, her appointee, was untenable. Tony Abbott's strong performance sought to cast all blame for Slipper's antics onto the Prime Minister, in the tradition of the-buck-stops-here.
But clearly her barely contained rage against Abbott's ''repulsive double standards when it comes to misogyny and sexism'' marks a watershed in her performance as Prime Minister.
She finally said enough is enough in a searing and emotional speech that hit directly at the Opposition Leader's style and behaviour, notably his sotto voce comments, directed across the table at her in question time.
She was on fire when she hit back at his call for her to, ''politically speaking, make an honest woman of herself''. ''That would never have been said to any man sitting in this chair,'' the PM said in her address.
For the first time, the Prime Minister told the nation how angry she was at Abbott calmly standing with the ''ditch the witch'' sign at an anti-carbon tax rally, while another placard described her as ''Bob Brown's bitch''.
''I will not be lectured about sexism and misogyny by this man.''
The nation has not seen this combination of fury, anger and indignation before from Gillard.
Abbott marred his robust performance by claiming the government was dying of shame. This echoed Alan Jones's despicable reference to the PM's father.
Even though the broadcaster has apologised for that, it would not be surprising if Jones claims today the PM was ''screeching'', the type of sexist put-down of strong women favoured by male shock jocks.
In Parliament, Team Gillard appeared to be taken by surprise when Abbott launched the motion calling for Slipper to be sacked immediately after his text messages were published.
It looked to be a tactical win, backed by strong rhetoric. But the unprecedented strength and passion of Gillard's comeback left the Coalition mute.
There was silence when she mocked Abbott's motion. ''He needs a mirror,'' she said.
No government dances to the opposition's tune. Therefore Labor described the opposition's motion as akin to a kangaroo court.
That view was given gravitas when it was put by Mark Dreyfus, a QC on Gillard's frontbench. It was Labor's way of avoiding addressing the need to sack Slipper.
With the independents split, the government scraped across the line, winning the division by just one vote.
Slipper had to leave the Speaker's office because, as Abbott said, he was bringing the Parliament into disrepute.
Before his resignation, Slipper had apologised unreservedly for the text messages, with the lame excuse they were supposed to remain private.
Even then, Gillard had alluded to further action when the court proceedings are finalised.
How Slipper votes in this history-making Parliament will be fascinating to watch. In the very unlikely event he creates a by-election, all bets are off.
Ross Peake is The Canberra Times Political Editor