Michael Brown: Prepare for retirements – and even resignations

MPs' mail is usually collected daily from the members' post office, just off the lobby outside the Commons chamber, by their secretaries or research assistants. But, from my own experience, whenever an MP is expecting an embarrassing item of correspondence he or she will collect the bundle of letters in person. This morning MPs will be furtively checking for the communication from Sir Thomas Legg, before their secretaries get there first.

This will turn out to be a damp squib. Many MPs, including Gordon Brown, may find that there have been mere technical breaches of the rules. The voluntary repayment of a few hundred pounds for carpet cleaning may resolve the matter.

According to Sir Stuart Bell, a member of the Members' Estimates Committee, the remit given to Sir Thomas was "to respect the decisions of the Fees Office in accordance with the rules at the time". Many MPs are worried, however, that if they are told to repay money it will be according to the prevailing standards of today.

But the biggest danger is for those in the Cabinet and Shadow Cabinet who escaped the earlier summary justice that Gordon Brown and David Cameron meted out to more disposable backbenchers. A general feeling of unfairness – that the party leaders protected their chosen friends – has pervaded the corridors of Westminster, and it will be interesting to see whether high-profile frontbench expenses claimants are forced to resign.

I suspect that the nightmare summer recess during which many have been on the receiving end of constituents' sharp tongues will encourage further retirements in the coming weeks. I heard of one MP's wife, loyally shopping in the local constituency high street butcher, leaving in tears as – in front of a shop full of customers – the butcher gave her the receipt: "I know you need this to claim the weekend joint off the taxpayer."

This saga will rumble on until, later this year, Sir Christopher Kelly announces the new rules on pay and expenses. Pressure is mounting for the party leaders to agree, in advance, to whatever he recommends. Frankly, the issue will only be resolved on polling day next May, when over 300 new MPs are expected to be elected.

On the basis of the sample local leaflets Tory candidates showed me last week at their conference, most won't even be claiming for so much as a bus ticket. The power of incumbency will have given way to the purity of the newcomer.