Conservatives outnumbered two-to-one in audience for BBC Question Time debate

Up to two thirds of the audience in Thursday’s Question Time Leaders’ debates will be left wing, The Telegraph can disclose.

The numbers of Labour and Liberal Democrat voters in the audience for the programme will reignite the row over audience bias which dogged the last election debate.

The Tories' David Cameron, Labour's Ed Miliband and the LibDems' Nick Clegg will be quizzed separately during the 90 minute in that order.

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The make up of the studio audience for the last BBC “challengers” debate two weeks ago was controversial after Ukip leader Nigel Farage complained that it was biassed towards leftwing parties.

The 150-strong audience will be broken down using a ratio which vastly exaggerates the proportion of people who are likely to vote Liberal Democrat on polling day next week.

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The BBC said that the audience – which have applied for tickets - will comprise 25 per cent each for the Conservatives, Labour and the Liberal Democrats.

Fifteen per cent of the audience will be the supporters of the minor parties such as the Green Party and the UK Independence Party.

Ten per cent will be classed as “undecided” and divided equally between the Tories, Labour and the LibDems.

The breakdown means that as much as two thirds of the audience could be left wing – likely to vote for Labour, the LibDems or the Greens.

The composition of the audience is highly relevant because only they will be able to submit questions to the three party leaders.

Andrew Bridgen, a Conservative MP who has been long term critic of the BBC, said: “This confirms what we have known for a long time – the unashamed left wing bias of the BBC.

“When you see the unrepresentative make-up of the audience in the most important Question Time programme for five years the BBC are not even subtle about.”

There will also be three special programmes broadcast on BBC One in different parts of the UK, in which Nicola Sturgeon, Leanne Wood and Nigel Farage will each answer questions for half an hour.

In a blog posted on Wednesday evening, by Ric Bailey, the BBC’s Chief Political Adviser, defended the composition of the audience.

He said: “The thinking behind this is that it will ensure that there’s a level playing field. Each leader engages the audience on the same terms.

“It also means that the BBC has done all it can to ensure that each leader gets the same shot at a fair hearing with the much bigger audience at home.”

He added: “There is no perfect mathematical way to assemble an audience for these sorts of programmes.

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“Some people think you should do it simply by current opinion polls; others that you should do it according to fixed ratios, such as representation in the House of Commons, or the formula used for Party Election Broadcasts.

“The fact is, you may well need to take account of all of these factors and more, not least the differences in different parts of the UK.”

BBC Question Time Election Leaders Special, hosted by David Dimbleby, will be broadcast from Leeds Town Hall live on BBC One and can be heard on BBC Radio 5 Live from 8pm to 9.30pm.