Imagine this. The trial of the alleged killer of a young woman is just about to commence. But then we learn that the judge has recently had a friendly dinner with the defendant's parents, even though he knew that he would soon be trying their son. What would we think? Once we had got over our astonishment, we would without hesitation conclude that a new trial must be arranged and that the wining and dining judge should never be allowed to sit on the bench again.
Now consider the social habits of the Prime Minister, David Cameron. Over Christmas, he and his wife, Samantha, had dinner with a neighbour, Rebekah Brooks, who is the chief executive of News International. Yet the government over which Mr Cameron presides is just about to determine whether News International should be allowed to buy the 61 per cent of BSkyB that it does not already own.
In making its decision, the Government is also conducting a sort of trial. News International makes its case; the objectors, of whom there are many, explain why the deal is against the public interest. Mr Cameron isn't personally conducting the proceedings, but he has sent a signal to those who do. It's not hard to decode. Translated, it reads: "I am the Prime Minister and I have esteem for News International".
Asked about this display of partiality when a quasi-judicial process is under way, the Prime Minister's officials could respond only that Ms Brooks is a constituent. It is difficult to know what to make of this excuse. Was it all that the staff could bring to mind on the spur of the moment? Or was it two fingers up to the rest of us? At all events, it now turns out that one of Rupert Murdoch's sons, James Murdoch, chairman of New Corporation in Europe and Asia, was also present. He is not a constituent.
In part of his mind, Mr Cameron comprehends that he was wrong to meet executives of News International socially at this time. If you asked him, he would say that of course the Prime Minister of the day, along with the monarch, has to embody the nation's highest standards of probity and fair dealing. You know the decent-chap look he would assume and the tone of voice he would use, calm and straightforward. He perfectly well realises that those called upon to make a judgement in a case involving two parties must be independent of either. Had he been asked to write an essay about this when he was a schoolboy at Eton, he would have turned out a good piece of work. He knows, he really does know.
Or he did. Unfortunately, the Prime Minister has succumbed to a dangerous condition, moral blindness. Intelligence and knowledge are no protection. It is brought on by strong emotions, such as anger, or greed, or sexual appetite. In Mr Cameron's case, it can be diagnosed very simply. It is the desire to hold political power for as long as possible, which is a sort of greed. That is what has clouded his judgement. His unspoken thought is that in order to win the next general election he must at all costs have the backing of News International's newspapers, the News of the World, The Sun, The Times and The Sunday Times. There is the supreme necessity. When necessary, the Murdochs must be appeased. Nothing else matters.
The crucial question is how widely does this writ run? If the only sensitive matter in which both News International and the Government were concerned was the issue of the acquisition of BSkyB, then perhaps the rest of us could relax after all. But News International and the Government also collide on the issue of the News of the World's use of private investigators to gain illegal access to the mobile-phone messages of people of interest to the newspaper. In 2007 Scotland Yard obtained the conviction of the paper's royal correspondent, Clive Goodman, who was jailed for four months. His editor had been Andy Coulson, who resigned two weeks later and then went to work for Mr Cameron as one of his most important advisers. He resigned last week.
Since the Goodman case, the country's largest and most important police force – an arm of government, let us remind ourselves – appears to have adopted a policy of masterly inactivity, a fortunate stance from the point of view of News International.
Never mind that during the investigation of Goodman, it became clear that this was not an isolated incident and that phone-hacking techniques had been used widely. Never mind that substantial payments were made to three further victims. Never mind that in March 2010, the News of the World settled a case brought against it by the publicist Max Clifford for intercepting his voicemail. Never mind that in April 2010 documents from the Crown Prosecution Service showed that the Scotland Yard inquiry had actually uncovered more than 4,000 names or partial names and nearly 3,000 full or partial telephone numbers from the materials seized from Goodman and the private investigator he employed.
Until finally on 10 December last year came this statement from the Director of Public Prosecutions, Keir Starmer QC. He said: "There is no admissible evidence upon which the CPS could properly advise the police to bring criminal charges ... [the various press reports] are not enough for criminal proceedings unless those making allegations are prepared to provide the police with admissible evidence to support their assertions. None have been prepared to do so."
Which is strange indeed. For it must be an everyday occurrence for a large police force to have to deal with witnesses who are frightened of putting their names publicly to what they know. You cannot help thinking that dealing with such situations must be in chapter two of Policing for Dummies. Phone-hacking is not just a civil wrong but also a criminal activity under the Regulation of Investigatory Powers Act. Moreover, to what extent is it a rule that "those making allegations" must be prepared "to provide the police with admissible evidence"? If my house is burgled, do I have to present the police with admissible evidence neatly tied up in a pink ribbon?
I asked above how widely does the writ run of appeasing News International. We can say with confidence that, if it runs at all, it starts from 10 Downing Street. This is no change. Both Mr Cameron's immediate predecessors would go to any lengths to secure favours. Perhaps "writ" is too strong, meaning as it does "a written order issued by a court, commanding the party to whom it is addressed to perform or cease performing a specified act". But as we have an unwritten constitution, so we have writs that are unrecorded. And if it were spelled out, it would simply state: never offend the Murdochs. Nobody will say this in terms to the Department of Culture that is now handling media competition issues. Nobody has written it down for Scotland Yard's benefit. But this odious rule has become part of our unofficial constitution. That is how bad it is.