Mr Clegg, however, tries to dodge speculation about what his party would do in that event beyond demanding radical constitutional change as the price for entering any new government.

ECONOMIST: Nick Clegg's turbulent early months as leader

The programme examines the decision to use stealth taxes in the first Labour parliament of 1997, and the decision to dodge questions about tax rises in the 2001 election campaign - less than a year before the announcement of a big rise in National Insurance.

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