AS Britain's top policeman, we clearly have to place a great deal of faith in Sir Ian Blair's judgement.

But that faith is being seriously undermined of late by his worrying habit of putting his foot in it.

Sir Ian justifiably received heavy criticism over his handling of the aftermath of the tragic shooting of Brazilian Jean Charles de Menezes by anti-terror police.

Only six weeks ago he was forced into a humiliating apology to the families of Soham murder victims Holly Wells and Jessica Chapman after he said almost nobody understood why the killings had become the biggest news story in Britain.

And now he is having to scramble for survival over the revelation that he made six secret telephone recordings, including one with the Attorney General Lord Goldsmith.

Only by apologising and giving an assurance that "it would never happen again" did Sir Ian hang on to his job and earn votes of confidence from ministers.

But a pattern is building here which cannot go on. The people of Britain, and of London in particular, need to know that the man in charge of keeping them safe can be trusted to make crucial decisions.

If his actions continue to suggest that he is careless and accident-prone, then those votes of confidence will stand for nothing.

Sir Ian Blair may still be Britain's top policeman but there can be no doubt that he is only one more mistake away from getting the boot.