IFS to Tories and Labour: a plague on both your houses

Two main parties' plans 'not credible' but Lib Dem idea to put a penny on income tax is praised

The much awaited judgment of the Institute for Fiscal Studies was brutal and even-handed: a plague on both your houses.

A feature of every election campaign is the day when the thinktank that specialises in tax, public spending and government borrowing does a number-crunching exercise on the party manifestos.