One hundred Tory MPs, including the party leader Iain Duncan Smith, are demanding access to any Government files and e-mails held on them after it emerged that civil servants have been routinely told to check their background while preparing answers to Parliamentary questions.
The move could cause mayhem within Whitehall as civil servants scramble to root out references to MPs dating back to 1997, when Labour came to power.
David Davis, the Conservative Party chairman, led the orchestrated campaign yesterday by writing to Sir Richard Wilson, the Cabinet Secretary, asking to see any references to him in faxes, files and e-mails to see if civil servants had been "politicised".
"I am asking for this information to ascertain how much the civil service has been politicised under Labour, and what information is kept about opponents of this Government," Mr Davis said.
Several Liberal Democrat MPs, including Matthew Taylor, the party's Treasury spokesman, have already applied for their files under the data protection act. They found that civil servants had been making derogatory and personal remarks about them in e-mails.
Steve Webb, the Liberal Democrat's Work and Pensions spokesman, is preparing to complain formally to the Information Commissioner, Elizabeth France, about the Government's failure to provide him with e-mail traffic within the Department of Work and Pensions.
Mr Webb believes references have been deliberately shredded. "I think they have been shredded. I think they have been deleting like mad. I think they have been trying to cover their tracks," he said.