Redefining poverty will lead to ridicule, ministers told

Tony Blair's pledge to eradicate child poverty in Britain by 2020 will be undermined if the Government tries to "manipulate" measures of low income, he has been warned.

Two influential think-tanks have told ministers that any redefinition of poverty that produces dramatic changes in the figures would erode public trust. The Social Market Foundation and the New Policy Institute say the Prime Minister's ambitious promise has left the Government with a huge problem because poverty is unlikely to be wiped out under current measurements. They fear that redrawing the statistical definition of poverty will produce the same kind of cynical reaction that the Tories had to deal with when changing measures of unemployment.

The Department for Work and Pensions is trying to find the best way to gauge poverty in Britain and has published a consultation paper suggesting radical changes.

One of the options being considered by ministers is to follow Ireland with a measure of poverty that combines relative and absolute indicators. The measurement of so-called consistent poverty ended the practice of defining the poor as those living on less than 60 per cent of median income. Once it was introduced in Ireland, thedefinition resulted in new statistics showing poverty in the country had been falling substantially.

But the think-tanks argue that such a definition is too crude and that copying it in Britain would invite ridicule. In a report to be published today, the Social Market Foundation argues that changing the measurement of poverty along the Irish model is "not to be recommended".

The report says: "Any attempt to adopt this measure would result in allegations that the Government is 'manipulating' the figures.

"It might also have the effect of eroding public trust in government statistics."

Tom Startup, the report's author, suggested that Britain should follow America and introduce a "poverty line" to determine how much money families need to achieve an acceptable standard of living.

He said: "If we don't change, there is a danger that either the true scale and extent of poverty remains unnoticed or conversely that 'alarmist' views of the extent of poverty go unchallenged."

The New Policy Institute, which was commissioned by the Irish government to review its new definition of poverty, said that it had found the poor had become better off during the period but had still fallen further behind the rest.

The institute, which is part funded by the Joseph Rowntree Foundation, said it favoured keeping the definition of less than 60 per cent median income because it was used internationally and was the best measurement of real poverty.

Guy Palmer, the institute's director, said that he would prefer the Government to stick to its original target of cutting the numbers of those below the 60 per cent income level. It should also restate its objective "to have proportionally fewer people in income poverty by 2020 than any other developed country". He said: "Rather than manipulate definitions in this manner, we would much prefer the Government concentrate on achieving targets."

A spokeswoman for the Department for Work and Pensions said: "The Government is currently consulting on the best way to measure poverty. We are determined to tackle poverty and the complex issues surrounding it."