Backbencher Bob Marshall-Andrews has become the first Labour MP to publicly call for Commons Speaker Michael Martin to resign.
His call comes after police probing alleged Home Office leaks arrested Tory MP Damian Green and searched his Westminster office without a warrant.
An official under Mr Martin granted the search, but the Labour MP said the Speaker should be held responsible.
Mr Marshall-Andrews said he no longer had any confidence in the Speaker.
'Attack on the people'
Mr Green, the Tory immigration spokesman, was arrested last week and held for nine hours by the Metropolitan Police, while his homes and offices were searched, as part of an inquiry into allegations of leaks from the Home Office.
The move has provoked outcry among MPs from all parties, who say the police action represented a fundamental breach of their right to hold the government to account.
Mr Marshall-Andrews said the Speaker was guilty of "a deplorable breach of his duties to the house" and the office of an MP should be sacrosanct.
He said: "We should be allowed to do our principal job, our main job, which is to hold the government to account, relentlessly to hold the government to account.
What we want is a proper inquiry.... not restricted to the internal workings of the House of Commons
Former Lib Dem leader Sir Menzies Campbell
"And an attack on that job and that office is not an attack on [the MP], it is an attack on the people who they represent.
"There is no greater attack than raiding the office and removing files at the behest and with the consent of the Speaker. And that is, in a very real sense... an outrage."
Mr Marshall-Andrews said he did like Mr Martin and respected him as Speaker, but he could not and should not recover from the current row.
"If we go into the trenches in order to try to defend this then it would be seen as part of a lamentable history on civil liberties issues and it would do us terrible damage at this stage," he added.
Since the Metropolitan Police were allowed to undertake the search, many MPs have questioned whether the Speaker is doing enough to protect their rights and guard Parliament's ability to hold the government to account.
Former Lib Dem leader Sir Menzies Campbell told BBC Radio 4's Today programme that the Speaker was in "a very uncomfortable position", but he said he believed Mr Martin would not step down.
He said he thought that Labour MPs would rally round Mr Martin and that the government would keep him office in order to avoid a potentially damaging by-election to replace him.
"What we want is a proper inquiry.... not restricted to the internal workings of the House of Commons," Sir Menzies added.
Two Conservative MPs have also called for Mr Martin to stand down.
Mr Martin told MPs on Wednesday that one of his officials - the Serjeant at Arms - had allowed the raid by signing a consent form approving the search of Mr Green's office, without consulting him.
Mr Martin said he had known in advance about the search, but had not been told that the police did not have a warrant.
He added that the police had not explained to the Serjeant at Arms, as they should have done, that she was not obliged to consent to the search - or that a warrant should have been insisted upon.
However, Scotland Yard has insisted its officers did make it clear that they could not search an MP's office without permission.
Meanwhile, shadow home secretary Dominic Grieve has told the Daily Telegraph newspaper that the junior civil servant at the centre of the leaks inquiry - Chris Galley - should be sacked if he was responsible.
"If he's done the leaking, it's quite clear the [Home Office] has a right to dismiss him," he said.
"Of course it does. It's a breakdown of trust. He's made a choice, and he will have to live by that choice," he said.
On Monday MPs will debate Parliament's response to the episode.
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