Michael Martin defends himself in committee hearing: From BBC Democracy Live
The Metropolitan Police has "strongly" rejected a suggestion that a senior officer "bamboozled" Commons officials over the search of a Tory MP's office.
The Met was responding to evidence by ex-Commons speaker Michael Martin given to MPs investigating events around the search of MP Damian Green's office.
Lord Martin said another official had blamed police tactics for the Serjeant at Arms not alerting her superiors.
Mr Green was arrested in 2008 as part of a leaks inquiry but was not charged.
The police action was later ruled to have been "not proportionate".
At the time MPs were furious police officers had been allowed into the Commons to conduct a search without a warrant.
A cross-party committee headed by former Lib Dem leader Sir Menzies Campbell is looking at how Commons authorities should in future deal with requests for police searches.
Lord Martin told the committee he had been "let down" by Serjeant at Arms Jill Pay who failed to require a warrant for the search and had known about the police investigation for a week before Mr Green's office was searched.
I felt that I could not interfere with an anti-terrorism squad
Michael Martin Former Commons Speaker
But he said when he asked her to explain her conduct, her boss Malcolm Jack, the Commons Clerk and chief executive, had stepped in to say "that Chief Superintendent Bateman had bamboozled the Serjeant and tricked her into keeping the matter from her immediate superiors".
Mr Bateman is the officer in charge of Commons security.
Committee chairman Sir Menzies Campbell told him that was an "allegation of the utmost seriousness" but Lord Martin maintained that was what had been put to him, although he had personally always found the officer "professional and courteous".
Asked if he believed the police had targeted Ms Pay for consent because they did not think they would be able to get a warrant, Lord Martin said: "We have a word in Scotland called 'sleekit' (cunning) and they were being sleekit, they were doing it in a sleekit way to get in."
A spokesman for the Metropolitan Police said he was "surprised" by the suggestion.
He said: "At no point did Chief Superintendent Bateman, or any officer from the MPS, attempt to 'bamboozle' or 'trick' anyone in this matter and we strongly refute this.
Mr Green was arrested last November and held for nine hours
"There is a clear audit trail, including a letter and signed search consent form, which supports this and which will be presented to the committee at the appropriate time."
He added that Lord Martin had never raised the allegations with them before.
Lord Martin, who said he was in Glasgow at the time of the search, had assumed a warrant had been granted and was "shocked" to hear later there had not been one.
But he said he had not asked if there was one because "it never occurred to me that the Serjeant would give consent to a police search... without a warrant".
He admitted there had been "serious failings in communications and management" in the way it was handled.
Lord Martin said the Serjeant at Arms had told him counter-terrorism officers were investigating an unnamed MP and could wish shortly to arrest them.
He said: "In my mind I had an idea of Islamic or Irish terrorism. I had no idea at the time of the very different type of offence of which Mr Green was being accused."
He said "it was frightening to hear about a terrorism group" - although he admitted he had known the alleged offence was of conspiring to commit misconduct in a public office.
But he said he had been warned two years earlier, by a High Court judge seeking to lift the Wilson Doctrine - which stops MPs' being bugged - "members of Parliament can get into difficulties and can be involved in illegal organisations".
He added later: "I was dealing with an anti-terrorism squad. I didn't know all the facts. I felt that I could not interfere with an anti-terrorism squad."
The furore over the police search of Mr Green's office led to a huge political row and put a lot of pressure on the then Speaker - who later resigned over his handling of a separate issue, MPs' expenses.
Ashford MP Mr Green was never charged but was held for nine hours by counter-terrorism police as part of an investigation into leaks from the Home Office.
An official inquiry into events later ruled the police action had not been "proportionate" and the leaks had never threatened national security.
Christopher Galley, the civil servant arrested for leaking documents to Mr Green, was also not charged but was later sacked for gross professional misconduct.
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