WHEN Ruth Kelly sat down in the House of Commons on Thursday lunchtime after fielding searching questions about sex offenders in schools she must have heaved a sigh of relief.

She survived probably the most determined assault on her position as Secretary of State for the Department of Education and Skills since she took up the post almost a year ago. But the problem is certainly not set to go away in spite of junior minister Kim Howells' admission that he made the decision.

MPs and children's groups around the country have demanded to know how PE teacher Paul Reeve was cleared to teach in a Norfolk school in spite of receiving a police caution for accessing banned images of children on the internet. They want to know how many more similar cases there are in schools, and where they are.

The evidence surrounding Paul Reeve was originally deemed inconclusive by ministers and so he was not placed on List 99 - the official blacklist of adults banned from working in schools.

This is a distinct grouping from the Sex Offenders' Register which is maintained by individual police forces around the country; appearing on one does not automatically mean inclusion in the other.

In a cool Parliamentary performance, Ms Kelly admitted that she was 'formally responsible' for all the decisions taken in her department including this one, and she announced an imminent review of rules that would bring List 99, the SOR and other data sources into 'much closer alignment', and close the gap between individuals cautioned and convicted of these offences.

This review would also look at removing ministers from making decisions in sensitive child protection cases and police taking a bigger role.

It has not been an easy time lately for the 37-year-old mother of four who began her Government role almost a year ago with such high hopes.

This latest row comes after a report that at least one million children were still being denied a decent education despite an extra £1 billion spent trying to improve ailing schools in the last 12 months.

There are also concerns about the ultimate delivery of Tony Blair's much-vaunted education reforms.

The last year has been closely watched by the constituents who saw her beat sitting Conservative MP Tom Sackville in 1997 by 7,000 votes.

The Northern Ireland-born pharmacist's daughter - educated at Queen's College, Oxford and the London School of Economics - won the seat just a week before her 29th birthday and 11 days before she gave birth to her first child.

In the Commons, she quickly became a favourite, a Blair Babe, and was made parliamentary private secretary to Nick Brown at the Ministry for Agriculture.

Gordon Brown snapped her up to become his economic secretary in 2000, swiftly promoting her to the more senior post of financial secretary a year later where regular Front Bench appearances caught the eye of Tony Blair.

He took her to work in the Cabinet Office to help mastermind Labour's election campaign, and when Home Secretary David Blunkett's resignation prompted the moving of Charles Clarke from Education, she was given the job.

The appointment, however, was not without controversy.

She has strong religious views, especially about abortion and contraception, and championed a number of moves to underpin family life.

She is also a member of fundamentalist Roman Catholic organisation Opus Dei - depicted unfavourably in Dan Brown's blockbuster novel 'The Da Vinci Code' which is just about to be released as a film starring Tom Hanks.

Given her strong moral stance, it is ironic that the strongest challenge yet to her ministerial role has been precipitated by a storm over a man who accessed child porn teaching in school.

A week, they say, is a long time in politics and it is likely that, in Ruth Kelly's case and given the mounting storm, the next one could be crucial.