MP DEREK Conway, at the centre of an expenses scandal, could face a criminal investigation after a senior police officer asked Parliament why the case had not been referred to the police.

The Old Bexley and Sidcup MP was suspended from Parliament for 10 days, fined more that £13,000, and suspended from the Conservative Party after the Commons standards committee found he had overpaid his son, Freddie, for work he carried out while a full-time student in the north east.

Metropolitan Police Commissioner Sir Ian Blair told the police authority that a senior officer in the specialist crime directorate had sent a letter asking why the matter had not been referred to the Metropolitan Police Service (MPS) for investigation.

Sir Ian said: "What we have done is to write to the standards commissioner and ask him whether he is going to refer the matter to the MPS and if he isn’t what are his reasons and we await that answer."

A spokesman for Commisioner John Lyon said: "The commissioner had looked at referring it to the police, but based on the evidence they did not think it would not be necessary. There has been no change in that."

Derek Conway echoed the words of the commissioner.

He said: "Sir George Young, Chairman of the Committee on Standards & Privileges mentioned the police aspect in his speech on the report and told the House that they had taken independent legal advice which had been that this was not an appropriate matter for the police.

"What Sir Ians says now is matter between the House authorities and him - I have no comment on that."

When asked if he would be seeking legal advice, he added: "This is not a game for me, it is a serious matter and I have nothing to add to what I have said."