Professor Steve Webb (Northavon, Liberal Democrat)

I have some sympathy with the hon. Gentleman's comments. When prediction is involved, there will be a grey area between people who, in good faith, make a mistake about how many hours they will work or what there income will be and those who wilfully misrepresent their circumstances. The division between those two groups is far from clear cut. The longer we allow matters to continue unreviewed,

unchecked and unassessed, the greater the danger and the larger the sums that will be involved.

In a similar vein, a corresponding danger exists for underpayments. The longer the set period of assessment, the more suffering that will occur for someone whose circumstances change and whose award is too low relative to what they would be entitled to were they reassessed. One could argue that if a person lost overtime or one day's work a week, they would know that they were worse off so would ask for a reassessment. However, we know that the world is not like that in reality. There will be a threshold for making reassessments and if a person stands to gain £5 a week of tax credit because of a change in circumstances, they may not pass the threshold for reassessment. In practice, a person would have to work out whether what had happened to them was big enough to warrant reassessment—we will be getting into difficult sums. If something happens in month three of a sixth-month period, people might get by for two or three months, then have a reassessment and catch up. However, what happens when something occurs in month one and the person does not get reassessed for 11 months? Lasting 11 months on an inadequate income—

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