By Mark Wallace
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Their most awkward moment came as their leader stood in for the Prime Minister at PMQs. Veteran eurosceptic Edward Leigh brandished a Lib Dem leaflet from 2008, asking whether the person claiming to be Nick Clegg who promised "a real referendum on Europe" was "an imposter or a hypocrite"?
At the time, this was a pledge Clegg felt strongly about - going to the point of trooping his MPs out of the Commons when the Speaker rejected an amendment proposing an EU referendum.
Obviously his position has changed, and he now seems dedicated to stopping the people getting a say.
The Deputy PM's standard get-out nowadays is to point to his party's 2010 manifesto (with no justification for the change in policy since then). It said:
"The European Union has evolved significantly since the last public vote on membership over thirty years ago. Liberal Democrats therefore remain committed to an in/out referendum the next time a British government signs up for a fundamental change in the relationship between the UK and the EU."