Queensland Liberal National Party (LNP) bosses believe Peter Slipper had long planned to betray them, saying he intended to sabotage LNP colleagues during the coming state election.
The LNP state executive met to consider a litany of complaints against the Fisher MP, who resigned from the party on Thursday and accepted the role of speaker of the lower house of federal parliament.
Mr Slipper faced losing preselection for his Sunshine Coast seat from a challenge from former Indigenous Affairs Minister Mal Brough and was unpopular among party members in the area.
He had also been in hot water over travel and other allowances.
The state executive convened on Wednesday to discuss whether disciplinary action was required after Mr Slipper snubbed former prime minister John Howard to attend a local function with Foreign Minister Kevin Rudd.
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It reserved its decision, but after Thursday's dramatic events, state director Michael O'Dwyer issued a strongly worded statement.
He said the executive had considered a series of complaints against Mr Slipper, including, "an act of gross disloyalty committed against his federal and state colleagues, grassroots members of the LNP and the organisational wing of the party".
"In recent months, the LNP has been inundated with complaints from local grassroots members of the LNP, who have expressed serious concerns about the behaviour and actions of Mr Slipper," he said.
"It was the party's view that those matters be investigated in a thorough, deliberate manner which afforded Mr Slipper the right of natural justice and a fair hearing."
In addition, Mr O'Dwyer said the executive had learned Mr Slipper had told a third party he intended to resign during the coming state election campaign, "to purposely create a serious distraction for his state colleagues".
"Further evidence presented to the party confirmed that Mr Slipper had been planning for some time to leave the Liberal National Party and this evidence confirms Mr Slipper's actions today were premeditated and in train for an extensive period of time," Mr O'Dwyer said.
"In accepting the nomination for the role of speaker of the federal parliament, the state executive has determined Mr Slipper has betrayed his colleagues in the federal Liberal and National parties."
The executive has accepted his resignation.
As Mr Slipper was led to the speaker's chair by his two Labor nominees, opposition MPs called out "shame on you" and "hang your head in shame".
His decision gives Labor minority government an improved buffer in the lower house.
