MPs were accused last night of seeking to escape repaying expenses by using “go-slow” tactics so that they can quit Parliament next year with bank balances, and a five-figure redundancy payment, intact.

Sir Thomas Legg, who has conducted an audit of the past four years’ of expenses claims, is understood to have complained that dozens of MPs were deliberately obstructing his inquiry.

A hard core of Members appear determined to avoid repaying expenses, previously approved by the Commons fees office, but retrospectively deemed out of order by Sir Thomas.

Many are among the 100 who have already announced they are retiring at the next election, prompting concerns that some of the worst offenders could be let off scot-free.

Sir Thomas, who asked hundreds of MPs last month to provide further information to justify claims for second-home allowances, had hoped to send out final bills this week.

In a large number of cases, however, he has been unable to do so because MPs have failed to provide the required documents.

“Legg is frustrated. In trade union parlance of the 1970s, there are MPs who are on a ‘go-slow’ and stringing this thing out. A lot are exploiting the postal strikes or using other excuses,” said a Commons official close to the process.

“Some are being very literal in their interpretation of the original letter and withholding material which would be useful. Others say, with varying degrees of justification, that they can’t find the paperwork.”

The Kelly report recommended that MPs found guilty of serious misconduct should be stripped of their resettlement grant, currently worth up to a year’s salary depending on age and the number of of years served in Parliament.

The new regime, however, will not come into force until after the next election. That means Tories such as Sir Peter Viggers and Douglas Hogg, who claimed for duck islands and moat cleaning, will be eligible for a grant of £64,766 next year. So too will Elliot Morley, the Labour MP who faces possible prosecution for claiming interest payments on a non-existent mortgage.

The Kelly report said: “It would be highly undesirable for any MP leaving Parliament at the next election after seriously abusing the system to receive a payment widely regarded as a ‘golden goodbye’ .” Although it suggested that the Commons Standards and Privileges Committee could withhold resettlement grants, subject to a vote by MPs, this power has never been used.

An official said yesterday that any such action “would be in completely uncharted legal waters and it might be challenged in the courts”.

The standards committee, already burdened with several high-profile cases from the expenses scandal, is concerned that it would be unable to cope with another load. One member said: “A race against time before MPs retire would be hard to win.”

David Curry, the committee chairman, said: “We need to analyse exactly what the implications are [of this] at the earliest opportunity, especially as there is going to be a very significant turnover of MPs at the next election.”

Alan Simpson, a Labour MP who is retiring next year, has already told the Legg inquiry that its demand for a £500 repayment of cleaning expenses would not stand up in court.

“Despite pressure from our political leaders, some MPs are reluctant just to roll over,” he said yesterday. “Those of us who are retiring are in a stronger position and Kelly may have persuaded more they don’t want to remain in politics.”

Jane Kennedy, another Labour MP, confirmed yesterday that some of her colleagues were considering paying money to local charities rather than the Commons authorities. “They really don’t think they have done anything wrong,” she said.

Sir Nicholas Winterton, a Conservative also retiring next year, said that many of his colleagues were having “genuine difficulty getting hold of the correct documentation”, which had in some cases been lost by the fees office.

While withdrawing the resettlement allowance would be appropriate in cases of genuine fraud, he added: “I would be reluctant to apply such a sanction to those whom Legg has deemed owe money only because he has changed the rules retrospectively.”

Frank Cook, a Labour MP who has been deselected in his constituency of Stockton North, has repaid some expenses but is querying demands for others. He said: “Legg said I had paid too much for a refrigerator. I have told him, if he will please provide me with a copy of the guidelines that existed on that I will think about it. He has to justify asking me for money back just as much as I have to justify claiming the money in the first place.

“I really don’t wish to cause Sir Thomas any frustration and exasperation. I am exasperated and frustrated enough for both of us. But I won’t pay up without justification and, if the one they provide is not good enough, I will tell them to p*** off.”

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