Police officers will have to inform the Commons authorities before approaching MPs in the course of an inquiry, Speaker Michael Martin has said.
Commons Speaker Michael Martin has rebuked a Conservative MP amid a fresh row over police entry to MPs' offices.
This follows allegations by a Tory MP that police entered his Commons office without a search warrant demanding to see constituency correspondence.
Daniel Kawczynski alleged that police had entered his Commons office without a search warrant demanding to see constituency correspondence.
Daniel Kawczynski said he found the episode "disgraceful".
But the Speaker said the officer had acted in "good faith" and said the MP should have checked his facts before "rushing to judgement" over the matter.
But Mr Martin said the officer had sought the MP's help beforehand and had not required a search warrant.
The Speaker said he would change rules on police procedure in the Commons.
The Shrewsbury and Atcham MP said he had handed over a Shrewsbury-postmarked letter related to an inquiry over "white powder" sent to a minister.
From now on, police officers will have to inform the Commons authorities before approaching MPs in the course of an inquiry.
Daniel Kawczynski said on Wednesday evening, in a statement in the Commons, that he found the episode "disgraceful".
'Take a breather'
The Shrewsbury and Atcham MP said he was informed about the police's intentions while taking part in a debate and his staff felt under a "certain duress" to hand over information related to an inquiry over "white powder" sent to a minister.
Mr Kawczynski said it was to his "eternal shame" that he had complied by handing over the letter.
Mr Kawczynski said it was to his "eternal shame" that he had complied by handing over the letter.
His comments follow the arrest of shadow immigration minister Damian Green and the search of his Commons offices.
Responding to Mr Kawczynski's allegations on Thursday, Mr Martin said the officer - stationed in Parliament - had sought the MP's help beforehand and had not required a search warrant as the information he sought was not privileged.
Responding to Mr Kawczynski's allegations, Speaker Michael Martin said the officer in question - stationed in Parliament - had sought the MP's help as part of an investigation into the sending of substances to high-profile figures including MPs.
The MP would have been advised to get his "facts together" and "give himself a breather" before making comments which could "reflect badly on professional people who are doing a decent job of work", the Speaker added.
He said the officer had explained the nature of his inquiry to the MP's staff beforehand and that he had agreed to meet him and hand over the requested document.
The Speaker said the officer had acted with "good intentions".
However, he added that given the current sensitivities over parliamentary privilege and the work of MP's, in future police would have to inform the Serjeant At Arms, who is responsible for security in Parliament, before making enquiries to an MP.
'Important case'
Scotland Yard has said the officer had entered the office "by appointment".
Scotland Yard has said the officer had entered the office "by appointment".
Mr Kawczynski said the investigation related to a letter sent to Schools Secretary Ed Balls, which contained white powder that later turned out to be flour.
The row follow the arrest of shadow immigration minister Damian Green and the search of his Commons offices in November which aroused widespread anger among MPs.
This had been sent from his constituency, he added.
Given the current sensitivities over parliamentary privilege and the work of MP's, Mr Martin said police, in future, would have to inform the Serjeant At Arms, who is responsible for security in Parliament, before making enquiries to an MP.
Mr Kawczynski said he had received a phone call from an assistant telling him that police were searching his office.
Speaking in the House of Commons on Wednesday evening, he used a point of order to raise the matter, saying: "I am extremely shocked at what I am going to say."
Mr Kawczynski added: "I received a note from my office that there was a police officer in my office demanding to see correspondence.
"They were already present in my office and I went down to see them after making my speech."
'Appalled'
The police had been investigating an "important case", the MP said, involving correspondence sent to ministers and had wanted "handwritten samples" of letters received by him.
Mr Kawczynski said: "I was extremely appalled that the officer can behave in this way, to enter a Member of Parliament's office with no warrant and to demand constituency correspondence."
He said he would "have to live with" his decision to hand over the letter demanded by the police.
Mr Kawczynski told deputy Commons Speaker Sir Michael Lord: "After everything that has happened to Mr Green, I find it disgraceful that this is happening and I urge you to investigate."
Fellow Tory MP Tobias Ellwood demanded that Home Secretary Jacqui Smith make a statement to MPs about the matter.
'No search'
Sir Michael said he understood the "great concern" about the incident but had "no knowledge of this matter".
He told Mr Kawczynski: "If it is as you say it is, then it is obviously extremely serious and my advice would be that you should take the matter up with the House of Commons authorities as quickly as possible."
Sir Michael said he would refer the matter immediately to Speaker Michael Martin.
But a Metropolitan Police spokesman said: "At 1750 this evening an officer based at the Palace of Westminster entered a member's office by appointment concerning a local investigation.
"The investigation was concerning a series of letters received at the House containing non-noxious white powder.
"The officer did not request to search the office and no search was conducted.
"A piece of correspondence matching handwriting of those under investigation was removed from the office after permission was granted by the MP."
