Leading article: Sadly, Mr Dyke can't be the BBC's director general

THE TASK of finding a successor to Sir John Birt as director general of the BBC is far too important to be left to the politicians. It is thus disappointing that William Hague has intervened to prevent Greg Dyke, chairman of Pearson television, from being considered for the post. Indeed it is a bit of a cheek, given the extent to which the Conservative Party politicised the appointment of members of quangos during their time in office. But the appointment of the director general is not a matter for Mr Hague. Or, at least, it is not a matter that justifies such high-profile intrusion. He could, had he chosen to do so, have made his objections quietly, through the "usual channels". Instead, Mr Hague has needlessly placed the BBC's governors - who alone have the responsibility of appointing the director general - in a very difficult position.

The governors could not now appoint Mr Dyke, even if they were satisfied that he was the best person for the job. Mr Dyke is, after all, a superbly well-qualified candidate - and even the official Conservative spokesmen are careful to acknowledge this. It seems to be an unjust punishment for Mr Dyke to have his candidature for the post not only questioned, but publicly vetoed in such a distasteful fashion. For Mr Hague it may seem to be the first tangible "scalp" of his brief leadership of his party, but it in fact makes him look like a rather crude and juvenile politician, reinforcing the very negative qualities that have held him and his party back so badly.

Having chastised Mr Hague, and offered a heartfelt plea that this does not mark the beginning of a trend of politicians issuing spurious vetoes on public appointments, it has to be conceded that Mr Dyke's candidature is problematic. This is not, it is worth repeating, because of Mr Dyke's qualifications. He is, by all accounts, a quick-witted and enterprising broadcaster, with a fine record in investigative journalism. He saved TV-am (which was more than just a matter of giving Roland Rat his big break). He understands the central challenge facing the BBC today - the need to balance quality broadcasting with the mass audiences required to justify the licence fee. And, vitally, his commercial skills would offer a potent challenge to the threatened dominance of Rupert Murdoch's interests - which may explain the extraordinary virulence with which elements of the Murdoch press have opposed his candidature. There is no reason why Mr Dyke could not do Sir John Birt's job well. Except for one, that is - his donations to New Labour, of about pounds 50,000.

For there is one position that a political donor should never occupy. The job of director general of the BBC - the public service broadcaster - is a very special one indeed. It must be filled by someone who not only is free of political bias, but is seen to be free of bias. Mr Dyke fails this test. It is unfair - painfully unfair. Had Mr Dyke merely maintained close personal friendships, or given money to Labour in a clandestine fashion, then he might not have been subjected to this treatment. His reward, it seems, for his honesty and transparency, is to be ruled out. Few other jobs have to have such an exacting criterion applied to them. But it is enough to try to imagine that the Conservatives were still in power and that someone who had donated pounds 50,000 to them was to be offered the job of director general. "Sleaze" would have been the automatic cry, and rightly.

It is just as well for the BBC that Mr Dyke is not the only candidate. Alan Yentob, the BBC's director of television, has a record of creative efforts surpassed by few. Richard Eyre and Tony Hall are also outstanding candidates. The BBC governors should now be allowed to get on with the job of choosing the next director general quietly and, above all, free from further political interference - from any quarter.