Some of Tony Blair’s expenses claims, which the High Court last week ruled should be disclosed to the public, have been shredded. The documents, itemising Blair’s claims for household expenses during a year of his premiership, were destroyed in the midst of a legal battle over whether they should be published. All MPs’ expenses are funded by taxpayers.

It is a criminal offence to destroy documents to prevent their disclosure under freedom of information (FOI) laws, but Westminster officials say they were unaware that the files were the subject of a legal challenge. They insist they were destroyed by mistake.

All MPs are entitled to claim for home renovations, furnishings, domestic appliances and groceries with a tariff based on prices at John Lewis, the department store. MPs have for years refused to disclose details of their expenses, which average £136,000, more than twice their salaries.

This position became increasingly untenable with the arrival of FOI laws in January 2005. Since then a number of media organisations, including The Sunday Times, have been conducting a legal batttle for full disclosure of MPs’ housing allowance, currently worth a maximum of £23,083.

It has now emerged that some of Blair’s files covering claims for Myrobella, his constituency home, were destroyed by Commons officials after they rejected The Sunday Times’s FOI request in January 2005 to see his claims for £43,029 of public money covering a three-year period.

Norman Baker, who has campaigned for more transparency in his fellow MPs’ expenses, said: “How convenient that some of Tony Blair’s expenses have been shredded. This is either incompetence or obstruction of the Freedom of Information Act and should be properly investigated.”

The shredding of the files has emerged in documents from the protracted legal battle over MPs’ expenses. So far the efforts by the Commons authorities to block disclosure have run up legal bills likely to cost the taxpayer about £150,000.

Last week the Commons authorities failed in a High Court appeal to block the disclosure of the expenses of 14 MPs, including Blair and Margaret Beckett, the former foreign secretary.

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