A Labour MP has today written to the Metropolitan Police asking them to investigate the Commons expenses claims of the Lib Dem former Cabinet minister, David Laws.
Thomas Docherty said he was asking Scotland Yard to mount a criminal investigation after Mr Laws was found guilty of six breaches of parliamentary rules by the Commons Standards and Privileges Committee.
"If this matter was not referred to the police the public would rightly ask is there one law for David Laws, and another for them," Mr Docherty said.
"If anyone else had fraudulently obtained £50,000 and their defence was that they had done it to protect their privacy, then they would rightfully have had the book thrown at them."
Mr Laws now faces a seven-day suspension from the Commons after the Standards and Privileges Committee found yesterday that he committed "a series of serious breaches of rules".
In a personal statement to the Commons, Mr Laws apologised for deliberately concealing the fact that he was using allowances to pay rent to his partner James Lundie. But he insisted his only motive had been to avoid being outed as gay, rather than financial profit.
In his letter, however, Mr Docherty argued Mr Laws's claims were based on a "false premise of their relationship" and that he had submitted "fraudulent documentation" to the Commons authorities in order to create that impression.
He said also that, living as lodger as he purported to be, there was no reason for Mr Laws to claim for repairs and maintenance of the property, raising questions of whether "the real motivation was to benefit himself and his partner".
Scotland Yard declined to comment, saying that it did not discuss individual cases.
A Lib Dem spokesperson said: “Nothing which approaches criminal conduct has been found despite over a year of painstaking investigation of the facts. This is not a case for the police to take up as a result of the Commissioners findings.”
Three former Labour MPs, David Chaytor, Eric Illsley, and Jim Devine, have already been jailed for fiddling their expenses, while a fourth, Eric Illsley, and the Tory peer Lord Taylor of Warwick are awaiting sentence. A second Conservative peer, Lord Hanningfield, is awaiting trial.
Any police investigation would be a severe blow to Mr Laws's hopes of making a political comeback.
He was forced to quit last year as Treasury chief secretary just 17 days after taking office when details of his expenses claims were disclosed by The Daily Telegraph.
The Standards and Privileges Committee's recommendation he should be suspended for seven days is the toughest punishment it has handed down since Derek Conway was suspended for 10 days in 2008 for paying his sons for work they had not done.
Nevertheless a series of senior figures led by Prime Minister David Cameron and Deputy Prime Minister Nick Clegg rallied round yesterday to express their hope that Mr Laws could make a return to government.
In his report to the committee, Standards Commissioner John Lyon found that "any reasonable person properly seized of the facts" would agree Mr Laws had been in breach of rules against using expenses to rent from a partner, which were introduced in July 2006.
However, he went further and concluded that from April 2005 the MP was wrong to designate his home in his Somerset constituency as his main home, because he was spending more time with Mr Lundie in London.
Mr Lyon also said the MP had misled the Commons authorities since 2001 by filing documents which gave a "false impression" of his relationship with Mr Lundie.
Mr Laws was found to have paid his partner up to £370 per month above the market rent, and used expenses to contribute £2,000 to building works at the second London property they shared.
The report also revealed that Mr Laws admitted regularly putting in expenses claims just below the £250 threshold which would have meant receipts were required.
The Commons will debate the committee's recommendations on Monday, with Mr Laws's suspension expected to begin on June 7.