“Power without responsibility” is perhaps the phrase that best sums up the way the Murdoch family have built News Corporation over the years but the game-changing event of the phone-hacking scandal is leading us into uncharted waters.

After tipping everyone else overboard, James and Rupert Murdoch are the last two people left to take responsibility for the corruption, criminality, abuse of power and huge multiyear cover-up that has been exposed in Britain.

James Murdoch has now been called back to testify again before the UK parliamentary committee and will have little choice but to appear and try to maintain his fig-leaf defence about not being alerted to widespread phone hacking when approving the record £700,000 payment to Gordon Taylor. This occurred in April 2008, four months after James assumed direct responsibility for News of the World. Check out this full timeline of the scandal.

The full transcript of what Rupert and James Murdoch told the British politicians at their first outing is also well worth another read. This is the key exchange right at the end of the two-and-a-half hours of evidence:

Tom Watson: James — sorry, if I may call you James, to differentiate — when you signed off the Taylor payment, did you see or were you made aware of the “for Neville” email, the transcript of the hacked voicemail messages?

James Murdoch: No, I was not aware of that at the time.

Then legal manager Tom Crone and then News of the World editor Colin Myler have now clearly contradicted that claim, saying they explicitly told James about this email during a 15-minute meeting approving the Taylor settlement. However, James Murdoch has dug in and does have some lines of defence, including that he was never shown the email and that chief reporter Neville Thurlbeck was never mentioned by name.

The other key question that James Murdoch will face goes to precisely what he told his father. After all, consider these comments to the committee:

James Murdoch: What I have done, and what the company has tried to do, is take new information, adjust our course, behave with propriety, behave quickly, behave in a humble way with respect to what has happened and with respect to trying to put it right. That is what we are trying to do. It was enormously frustrating. That does not mean that I have any knowledge of anyone intentionally misleading me and the company. I don’t, which makes it doubly frustrating. We are where we are. New information emerged through the legitimate due process of a civil trial. The company acted on it as fast as could possibly be expected.

But the whole house of cards comes tumbling down with this:

James Murdoch: Now knowing then what I know now, would I have still directed to negotiate to settle that (Gordon Taylor) case? I would, actually, but I would have coupled it with the other actions that we have taken since the new evidence emerged at the end of September 2010. And that is to immediately go and look at whatever we can find internally around the individuals involved; to immediately contact the police about information that may be of great interest to them; to put in place the process, which took up a little while and we did it in the early part of 2011, around admitting liability to the civil litigants; putting a process in place to get to the bottom of what legitimate allegations there were; apologising unreservedly to the victims of those illegal voicemail intercepts, which were absolutely inexcusable; and having a system of compensation there.

So, James was aware of the new evidence in September 2010. The killer question for the committee to ask James is why he sat back in silence and watched his father say the following at the News Corp AGM on October 15 last year:

Rupert Murdoch: We have very very strict rules. There was an incident more than five years ago. The person who bought a bugged phone conversation was immediately fired and in fact he subsequently went to jail. There has been two parliamentary inquiries, which have found no further evidence or any other thing at all. If anything was to come to light, we challenge people to give us evidence, and no one has been able to. If any evidence comes to light, we will take immediate action like we took before.

James Murdoch knew his father was speaking rubbish. As a News Corp director, heir apparent and the executive with direct responsibility and knowledge why did he allow his father to broadcast this falsehood in front of the entire board and dozens of journalists and investors at the most important public governance meeting the company holds each year?

The answer will be most interesting indeed.