By Michael Crick
Political editor, Newsnight
Mrs Spelman recently took charge of improving the Tory record on expenses
Some Tory MPs are calling for party chairman Caroline Spelman to be sacked, after further evidence emerged about her payments to her nanny.
Mrs Spelman's secretary complained in 1999 that the Meriden MP was using Parliamentary allowances in this way, BBC Two's Newsnight has learned.
The matter was referred to the party's chief whip, who advised Mrs Spelman to stop paying her nanny via this method.
Mrs Spelman has previously stated she acted "entirely within the rules".
And shadow security minister Baroness Neville-Jones said she was "quite certain that Caroline has made it very clear that if she has contravened the rules, that she will do the right thing".
The money paid to Ms Spelman's nanny was "quite a small amount", the peer told BBC One's Question Time.
Newsnight has learned that nine years ago Mrs Spelman was "shopped" by her secretary Sally Hammond, who complained to the Conservative Party leadership that she was using Parliamentary allowances to pay her nanny.
Mrs Hammond could not understand why the MP had so little money available for office expenditure.
She was shocked to find that much of the annual Commons allowance was being paid to Mrs Spelman's nanny, Tina Haynes.
David Cameron is trying to ensure the Conservatives are sleaze-free
As far as she knew, Ms Haynes did little or no secretarial work to justify this.
Mrs Hammond took her complaint to Peter Ainsworth - then, as now, a member of the Conservative shadow cabinet, and for whom Mrs Hammond had once worked.
He referred the case to the then chief whip, James Arbuthnot, who was worried by what he was told, and told Mrs Spelman to stop paying her nanny from Parliamentary money at once.
Another of Mrs Spelman's previous Westminster secretaries was also unhappy that the nanny was being paid from public funds - which amounted to about £14,000 a year, I am told, or more than £25,000 over 22 months.
When Newsnight broke the Caroline Spelman story three weeks ago, Mrs Spelman herself referred the case to the Parliamentary Standards Commissioner, John Lyon, who is now holding an inquiry.
But we have learned the Conservative whips' office at Westminster began its own inquiries.
Mrs Hammond has discussed the matter with the deputy chief whip, Andrew Robathan, a personal friend.
She repeated what she said nine years ago, contradicted Mrs Spelman's own explanation of events, and said that if asked, she would say the same to the Standards Commissioner.
The Commons rules on when MPs could claim the office costs' allowance, the allowance then used to pay secretarial staff, were clear.
"Any expenditure must be incurred wholly, exclusively and necessarily in the performance of parliamentary duties" - those 10 words are highlighted.
"You cannot therefore claim for expenditure that is personal..."
On the day we broke the story we rang the nanny - Ms Haynes - and asked her what she did for Mrs Spelman.
She told us she "was working for her as a nanny" and did not do political stuff. She just answered the odd phone call, "took messages" and "passed them on to Caroline", and occasionally posted letters.
Conservative Central Office then came up with a different version of what happened and told the BBC that Ms Haynes - a qualified nanny - was employed for 30 hours a week in 1997-98, as a constituency secretary on the Parliamentary payroll.
At the same time, it said, she also worked as Mrs Spelman's nanny, but she did this for no pay.
The following morning Mrs Spelman made a statement backing up this story.
And later in the day Central Office helped Ms Haynes to put out a statement which claimed: "During the period of 1997 to 1998, I had two roles; one helping Mrs Spelman with childcare and another providing secretarial help to her as an MP."
The Conservative version of events soon began to unravel.
First they admitted that the unusual arrangement with the nanny had gone on for two years, not one.
Then it became clear that - at least at the start - Ms Haynes had been working at the family home in Knockholt, Kent.
This was further away from the constituency than even her Westminster office.
Then Mrs Spelman's claim that there was no other constituency office was challenged, since documentation shows that her current constituency office over the border in Solihull has always been listed as her office in official directories.
Separately, Janet Parry told Newsnight that when she did a stint of work experience over the summer of 1997, administration work was already being handled by the Solihull office at 2 Manor Road in Solihull.
We have now learnt that a number of Conservative MPs who are now familiar with Mrs Hammond's version of events have approached the chairman of the backbench 1922 Committee to demand that Mrs Spelman be sacked.