First Minister Peter Robinson will wake up this morning to face growing pressure over how much he knew about his wife’s financial interest in a business deal involving her teenage lover.
The astonishing series of allegations made in last night’s Spotlight programme takes the saga well beyond the embarrassment of the “inappropriate behaviour” which had been revealed by the Robinsons in their public statements on Wednesday.
Spotlight last night alleged that Peter Robinson became aware of money his wife had received from developers which was used to set Kirk McCambley up in business.
The programme said that while he pressed his wife to return the money, he failed to tell the proper authorities about the transaction despite being obliged to act in the public interest by the ministerial code.
Revelations about sexual indiscretions and questions over financial dealings can be damaging for any politician and any political party.
But the DUP is not just any party. Its roots lie deep in fundamentalist conservative Protestantism and a brand of religion personified by Ian Paisley, who founded it and towered over it as leader until 2008.
The key question now is: will the crisis facing the Robinsons impact on an already tarnished brand? The party has already had some tough times. Part of its traditional base was left in disarray by the 2007 decision to form a coalition with Sinn Fein.
This U-turn after years of bellicose opposition to both power-sharing and “Sinn Fein/IRA in government” has had electoral consequences.
Controversies on expenses have also proved damaging.
Now Iris Robinson’s personal downfall has left her open to a charge of hypocrisy.
It is often argued that a politician's private life is no concern of the media or voters. That is much harder to sustain when the politician and her party have been in the business of moralising at others. This is why sympathy for Mrs Robinson's current distressing plight is not as strong as it might be.
Defenders of Iris Robinson have been quoting the Bible about those without sin casting the first stone. It will be claimed by critics, however, that Mrs Robinson and her party have been throwing a fair few stones about in their time.
There are other Scriptural texts that could be cited, like “Judge not, lest ye be judged”.
To be fair to the Strangford MP, the DUP was mixing politics and religion — and making the personal political — decades before she was denouncing homosexuality as an “abomination”.
The party was formed in 1971 to replace Paisley's Protestant Unionist Party.
Its platform has often echoed the dogmatic theology of his Free Presbyterian Church. For example, the DUP manifesto for Assembly elections in 1982 included a section entitled “Moral Matters — Morals Matter”.
It pledged: “A strong and forthright stand will continue to be taken in accordance with Christian principles on the great moral issues of our day.
“The DUP will lead opposition in the Assembly to such matters as the legalising of homosexuality, opening sex shops and Sunday opening of public houses. Ulster should decide its own moral standards.”
A party manifesto three years later referred to it “recognising the laws of God and the inherent benefits of the Ulster Sabbath as part of our heritage”. Iris Robinson is by no means the only DUP politician of more recent times to bring her religion into politics.
In 2005 Ballymena DUP councillor Maurice Mills claimed the devastation of Hurricane Katrina in New Orleans was “God's judgement” over a gay festival in the city.
“Surely this is a warning to nations where such wickedness is increasingly promoted and practised,” he added.
“This abominable and filthy practice of sodomy has resulted in the great continent of Africa being riddled with Aids.”
In 2007 Ian Paisley jnr spoke in a magazine interview of being “repulsed” by homosexuality.
Peter Robinson, meanwhile, fully backed his wife's anti-gay stance, saying: “It wasn’t Iris Robinson who determined that homosexuality was an abomination, it was the Almighty.”
Obviously, DUP politicians are entitled to their opinions and to practise their personal faiths. But now one of their number has failed to live up to the exacting standards of righteousness demanded of others.
The fallout from that is hard to gauge at this early stage.
It just might lead to fewer |pronouncements from the political sphere on issues of private morality.