It’s bye bye for now to Lord Leveson and his long-running inquiry, which held its last day of hearings in London yesterday.

But, when the criminal trials of Rebekah Brooks, Andy Coulson, et al, are over, his Lordship may return to examine what happened at the News of the World in far more detail, unconstrained by fears of prejudicing people’s chance of a fair trial.

And in the meantime, the biggest question remains unanswered: who was behind the massive cover-up that took place at News International? Was it the Murdochs, as many suspect, or was it designed to ensure they never discovered what had gone on, as Rupert and James maintain? Whatever the answer, there is no dispute that it took place on a grand scale.

Back in February in London’s High Court, 37 hacking damages cases were settled in favour of the victims, on the basis, according to Justice Sir Geoffrey Vos, “that senior employees and directors of News Group Newspapers knew about the wrongdoing and sought to conceal it by deliberately deceiving investigators and destroying evidence”.

Note the word “directors” there.

Vos told the court he had seen evidence, which raised “compelling questions about whether you [News Group Newspapers] concealed, told lies, actively tried to get off scot free”. He then read out several court documents claiming that News had “put out public statements that it knew to be false”, had “deliberately deceived the police” and had destroyed evidence of wrongdoing, including “a very substantial number of emails” and computers. While not admitting these allegations, NGN had agreed to pay damages “on the basis of the facts alleged”, Vos told the court.

Note, “deliberately deceived the police”, “destroyed evidence” and “statements it knew to be false”.

In his closing speech to Leveson on Tuesday, one of the victims’ leading counsel, David Sherborne, delivered a devastating indictment of the way in which the News of the World had bullied, harassed and destroyed the lives of some of its hacking victims, before returning to this theme.

“Most interesting of all,” said Sherborne, “is the evidence we have of the cover-up, the deliberate destruction by News International of millions of emails, which took place whilst the newspaper’s executives were still peddling the line in public that this was just the work of one rogue reporter”.

“We now know … that this email deletion policy was being discussed and approved of at the highest, at the highest of levels within the company … And when did this mass deletion take place, you may ask. Well, at two critical times, as we can now tell. First, within days of the letter of complaint received from us in the Sienna Miller case landing on the desk of News International, asking to preserve all documents, as one does in civil litigation. And what about the second time that there was another mass cull? It was the day, the very day after the Director of Public Prosecutions, Mr Starmer, announced that he was conducting a comprehensive assessment into News International’s voicemail interception activities. I need say nothing more.”

We still don’t know who gave these instructions, but we know from Justice Vos’s judgement that a “previously-conceived plan to conceal evidence was put in train by NGN managers” in late 2010. We also know that Rupert favourite, Rebekah Brooks, was News International’s CEO at the time.

The other big unanswered question is why the Metropolitan Police assisted in this cover-up for so long. As David Sherborne told Leveson on Tuesday, the police uncovered “an Aladdin’s cave of evidence of serious wrongdoing” in 2006 but “shut the cave up as firmly as they could”.

“They had Mulcaire’s notebooks, they had worked out there were over 400 potential victims, they had pages of PIN numbers, passwords … call data … from within the News of the World … they had the ‘for Neville’ email and they knew about payments for stories … So why did they shut the cave?”

By sealing it up, Sherborne continued, “what they allowed News Group to do was not just to escape the full consequences of the criminality which they had perpetrated, they allowed News Group to peddle the lie of one rogue reporter”.

So why did this happen, Sherborne asked? Part of the answer may have been pressure on resources; but another was that the police and press, and the Met and News, were unhealthily close. They drank together, dined together, did each other favours and tipped each other off. Sherborne said:

“At a key moment in the hacking investigation, when the police had uncovered evidence of how widespread the practice was and were deciding what to do about it within News of the World, Messrs Hayman and Fedorcio attended a meal with Andy Coulson and Neil Wallis at an exclusive London members’ club. Whether they discussed it openly or not, which they deny, it doesn’t matter. But I wonder, would you have described the decision to meet and to have that dinner as a wise or a foolish one? And do you really need me to answer that question?”

At the time of that cosy lunch, Andy Hayman was the officer in charge of the phone hacking inquiry. He would later resign from the Met, amid allegations of rorting his expenses, and land a £10,000 a-year job as a columnist for News International.

Dick Fedorcio was the Met’s PR chief until he resigned in March this year. He is now facing gross misconduct charges for hiring Neil Wallis (see above) on £24,000 a year as a PR consultant to the police, after Wallis quit as deputy editor of the News of the World.

But finally, let’s get back to the Murdochs, because that’s the most interesting question of all. Did Rupert and James really not know what was going on? Were they, to quote a favourite line of Lachlan Murdoch’s and James Packer’s from the One.Tel fiasco in 2001, “profoundly misled”?

Back in May, the House of Commons hacking inquiry charged Rupert with “willful blindness” and “turning a blind eye … if … [he] did not take steps to become fully informed about phone hacking”.

The crucial word in that sentence is “if”.

The evidence against James is even more compelling, in that two senior News International executives — lawyer Tom Crone and NoTW editor Colin Myler — have sworn that they told him and that he saw damning documents which made the extent of the hacking clear. But unless criminal charges are laid over the cover-up, we may never know for sure.

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