James Murdoch 'knows nothing'
If James Murdoch's reputation took a further battering today, it was because he was forced to apologise for and deny knowledge of yet more wrong doing - including the covert surveillance of members of the select committee and of lawyers who represent victims of phone hacking by the News of the World.
It is never exactly good for chairmen or chief executives of big businesses to admit that serious malpractices have taken place in their organisations without their knowledge.
But of course if incontrovertible evidence were ever found that Mr Murdoch knew of or authorised the wrongdoing, well that would be a career-ending moment or worse.
Right now Mr Murdoch's immediate prospects depend to a large extent on who the MPs on the select committee choose to believe about one central issue, whether or not at a meeting in June 2008 he was made aware of the contents of a notorious email, the so-called "For Neville" email, which showed that phone hacking was more widespread at the News of the World than its owner, News International, was admitting.
Mr Murdoch insists he neither saw the email nor understood its significance. That's contradicted, in a variety of ways, by three former News International employees, Tom Crone, Colin Myler and Neville Thurlbeck.
The new material on this today was an account by Tom Watson, the Labour Party's deputy chairman, of a recent conversation with Mr Neville Thurlbeck, former chief reporter of the News of the World, in which Mr Thurlbeck said that he had been assured by Tom Crone that Mr Murdoch had seen the "For Neville" email.
James Murdoch denied (again) that this was the case.
Mr Murdoch insisted - on being asked by another Labour MP Paul Farrelly - that the debacle at the News of the World does not undermine his competence as an executive at News Corporation, parent company of News International.
But he also has another job, as chairman of British Sky Broadcasting, the TV giant in which News Corp has a 39% stake.
Later this month shareholders of BSkyB will vote on whether Mr Murdoch should stay as chairman.
Since News Corp is not an independent shareholder, Sky's non-execs are likely to turf him out if somewhere around a half of the other shareholders vote for him to go.
Will that happen? Impossible to say - but I understand BSkyB believes there won't be a shareholder rebellion on that scale (although a sizeable number of shareholders will vote against Mr Murdoch).
That said, there was probably little that emerged from today's select committee hearing to change the minds either of Mr Murdoch's supporters or his critics.