Parliament suffered its darkest day yesterday as MPs and peers were suspended for alleged misconduct and the Commons faced an exodus of shamed and demoralised Members.

MPs caught up in the expenses scandal admitted that they could be dropped by their local parties. Others were said by colleagues to be ready to walk away. Some who have been unaffected declared that the attractions of life as an MP had disappeared.

It was the grimmest time that most could remember, with many still fearful about future disclosures and none able to raise enthusiasm for immediate concerns such as the European and local elections. As the police were asked to investigate for fraud, yesterday’s developments engulfed MPs, peers and the Speaker:

Gordon Brown suspended a former minister who claimed £16,000 in expenses for a mortgage he had paid off;

A senior David Cameron aide resigned after claiming tens of thousands of pounds in second-home expenses on a London property that his wife, also a Conservative MP, designated as her main home;

Two Labour peers were recommended for suspension from the Lords — the first since Oliver Cromwell’s time in the 1640s — after accusations that they had shown themselves willing to change laws in return for cash;

Authority drained away from Michael Martin, the Speaker, after the Liberal Democrats effectively withdrew their support and MPs prepared to table a no-confidence motion.

To add to Mr Brown’s woes, a select committee has accused Lord Myners, his City minister, of incompetence over his handling of the pension of former bank chief Sir Fred Goodwin.

Party strategists warned Mr Brown that unless the gap with the Tories was closed swiftly, fundraising for the next election would be virtually impossible. A YouGov poll for the Sun showed Labour at its lowest ever level — 22 per cent. The survey of voting intentions for the European elections also found that the Tories had suffered, dropping 9 points in a month.

In the biggest shock of another 24 hours of revelations, Andrew MacKay, Mr Cameron’s main political and parliamentary adviser, resigned after the Conservative leader said that his expenses arrangements were unacceptable. The former deputy chief whip, who is married to Julie Kirkbride, MP for Bromsgrove, had been involved all week in top-level discussions about claims by Shadow Cabinet members.Mr MacKay has claimed £22,000 a year in second-home allowance on the couple’s London property. Ms Kirkbride made her second-home claim on her constituency house, nominating London as the main home.

Mr Brown suspended Elliot Morley, the former agriculture minister, from the Labour Parliamentary Party after it emerged that he claimed £800 a month in mortgage interest for 18 months after he paid off the loan on his constituency home. The MP for Scunthorpe faces potential expulsion from the party and has been suspended from his role as Mr Brown’s climate change envoy.

Although Mr Morley has repaid the money and said that his claims were “inadvertent”, legal experts said that he might have breached the 2006 Fraud Act and the 1968 Theft Act.

Matthew Elliott, of the TaxPayers’ Alliance, threatened a private prosecution if no police action was taken.

In the Lords, two Labour peers were recommended for suspension after a report on the “cash for amendments” scandal. The Lords Privileges Committee found that Lord Truscott and Lord Taylor of Blackburn “failed to act on their personal honour” by offering to help undercover reporters posing as lobbyists to seek amendments to government legislation in return for cash.

A former Conservative minister agreed to repay £2,200 after claims that it was used to clear a moat at his country home. Douglas Hogg also promised to claim no more second-home allowances for the remainder of this Parliament, worth about £10,000.

Last night Shahid Malik, the Justice Minister, became the latest MP to be named in the expenses scandal. The Daily Telegraph said that Mr Malik ran up the highest expenses claim of any MP, receiving second-home allowances of £66,827 over three years on his house in London. At the same time, the newspaper said, his main home was a three-bedroom house in his Dewsbury constituency that he rented for less than £100 a week.

In the Commons, MPs spoke openly of “throwing in the towel”. Those who haven’t been hit by disclosures said they were nevertheless getting abuse from voters. One senior Tory, who has already announced his resignation, said: “I’m glad I am going and wonder why I ever bothered to come here.”

Mr Morley admitted that his local Scunthorpe party would decide next week whether he should fight again.

Scotland Yard confirmed that it had received complaints about a number of MPs’ expense claims but would not say whether Mr Morley was among those. The allegations are being “considered” by fraud detectives.

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