BBC sidelining Sky election debate to avoid more Nick Griffin interviews

The BBC is resisting calls to screen tonight's election debate live on BBC1 or BBC2 because executives believe strict impartiality rules would force them to hand more airtime to BNP leader Nick Griffin if it did so.

BBC executives are worried that could prompt a revolt among senior journalists, many of whom are opposed to the amount of coverage the corporation has already devoted to Griffin.

Sky News, which will host the second debate in Bristol, has made the rights available to rival broadcasters, but the BBC has chosen to simulcast it only on BBC News 24. It will also be simulcast on Radio 4 and repeated on BBC2 at 11.30pm.

That is likely to restrict the size of the TV audience to a fraction of the 9 million who tuned in for the first debate on ITV1 last week.

The BBC has drawn up a detailed plan to ensure it meets its legal obligation to produce fair and balanced coverage next week, when it screens the third and final election debate on BBC1.

It has placated fringe parties who were angry at being excluded from the leadership debates by ensuring their leaders are handed airtime in TV and radio news bulletins.

As part of this plan, Griffin has been invited to take part in a lengthy interview on Radio 4's flagship daily current affairs show, Today, the morning after the debate.

Screening a second live debate would force the BBC to ask him on to the same programme again, meaning that Griffin will be interviewed twice in a high-profile BBC slot in as many weeks.

Executives are anxious to avoid a repeat of the angry scenes that greeted Griffin when he was a guest on Question Time last year.

A Twitter campaign has been launched asking the BBC to show the debate live on a terrestrial channel, but insiders insist there is no chance of a U-turn.

Another BBC source indicated that the BNP was not central to its thinking and what the corporation was keen to ensure was that licence fee payers could see or hear the debate, pointing out that 95% of households have access to Sky News or BBC News Channel on digital TV.

A BBC spokesman said it was "fulfilling its public service duty" by showing the Sky News debate on other outlets.

The BBC's strict election guidelines mean that the leaders of smaller parties such as Plaid Cymru, the SNP and the Green Party must appear regularly on the main news bulletins in prominent slots.

Handing the main party leaders a further 90 minutes of primetime coverage tonight would have presented BBC executives with a major headache. They have to ensure rivals are given a proportionate amount of time on similar outlets with large audiences, rather than simply ensuring they appear somewhere on one of the BBC's many services.

The BBC editorial guidelines state: "The way in which due accuracy and impartiality is achieved between parties will vary. It may be done in a single item, a single programme, a series of programmes or over the course of the campaign as a whole. But content producers must take responsibility for achieving due accuracy and impartiality in their own output and not rely on other BBC services to redress any imbalance for them."

Scheduling tonight's debate on the BBC News Channel will make it easier to ensure balanced coverage because it broadcasts 24 hours a day and reports on the BNP and others can be aired at any time.

At the time of Griffin's Question Time appearance, senior executives said privately that they feared the BNP could mount a successful legal challenge if they failed to invite him on the programme after it won two seats in the European elections in May 2009.

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