Catherine McKinnell MP, Labour's shadow exchequer secretary to the Treasury, said Iain Duncan Smith's tax credits criticisms were a "cheap political attack".
It goes without saying that the government should tackle fraud and error in the tax credits and benefits system, just as they should tackle the billions lost each year in tax avoidance and evasion.
Tax credits help ensure millions of families are better off in work and have lifted hundreds of thousands of children out of poverty.
This cheap political attack on the whole tax credits system will not succeed in acting as cover for the government's cuts to tax credits which will hit millions of striving working families next year.
Iain Duncan Smith should start focusing on sorting out his new universal credit which even his own Cabinet ministers are warning is 'a disaster in the making'.
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