Home Secretary Jacqui Smith is to make a statement to the Commons on the arrest of senior Tory MP Damian Green. Commons Speaker Michael Martin faced criticism and a call to quit Wednesday after it was revealed police raided Mr Green's office without a search warrant. The search was also authorised by the Serjeant at Arms without the Speaker's express permission. The focus now is expected to shift to the role of senior ministers when the Home Secretary delivers her own statement about the issues raised by the affair to MPs. She has already insisted she did not order the police probe into alleged leaks of documents to Mr Green, the Opposition immigration spokesman, and had no prior notice of his arrest. Passions ran high on both sides of the House as Tory MPs cheered Mr Green and Labour backbenchers accused the opposition of colluding in the leaks. Mr Green defended his use of documents leaked by Home Office official Christopher Galley which revealed information including the fact that 5,000 illegal immigrants had been cleared to work in the security industry. He said: "An MP endangering national security would be a disgrace. An MP exposing embarrassing facts about Home Office policy which ministers are hiding is doing a job in the public interest." But Metropolitan Police acting commissioner Sir Paul Stephenson defended his officers, insisting detectives in any inquiry, no matter how sensitive, must follow the evidence "without fear or favour". He said: "I would strongly refute that I or any senior officer under my command have or have allowed any improper influence of our operations or acted for political purposes. That is not what we do." Mr Cameron said the documents which Mr Green made public contained "things the public has a right to know and he was entirely right to publish them". Prime Minister Gordon Brown told him no-one could "pick and choose" when to support the operational independence of the police and pointed out the police said they were investigating "a substantial series of leaks from the Home Office, potentially involving national security".