Leading article: The end of the affair

Peter Robinson is being undone by his all-too-colourful wife Iris, whose sexual and financial exploits have combined to detonate Belfast's most spectacular scandal.

She has already fled from public life, and he cannot last long as Northern Ireland's First Minister. There are too many loose ends in the tale, too many avenues demanding exploration, too many lewd Iris Robinson jokes making the rounds. Authority and dignity have drained away.

But even if everything were, improbable as it seems, eventually convincingly explained, admissions have been made about Mrs Robinson's conduct. It began when she promised a dying intimate friend that she would look after his son. She then embarked on an affair with the son, who was aged 19. She was 59. The Robinsons are in a party with a strong fundamentalist strain: it was, after all, founded by Ian Paisley. Mrs Robinson has always been big on Christian family values.

In her frequent condemnations of homosexuality she points to the book of Leviticus, where the practice was roundly condemned. She omits to mention, however, that the same book also denounces adultery.

The accusations made against her are much more serious and more specific than those against her husband. She was an MP, a Belfast Assembly member and a councillor. The central charge against him is that he discovered she had been involved in public financial transactions without declaring an interest. The argument goes that various political codes stipulate he should have notified the authorities, but did not. He was also evidently unable – if, that is, he tried – to convince her to belatedly declare an interest.

In other words, the charges against the husband are much less grave than those against the wife. He would say he is being tarred with insinuation and innuendo, and it is true that he is suffering from guilt by marital association.

He tried to fix the political mess created by his wife, but failed. For months he has been gearing up to defend himself but what has emerged is closer to a tsunami than any manageable political squall. A once-proud, powerful and moneyed political dynasty is being swept away.