The News Corporation chairman and chief executive has been roundly criticised by the cross-party Commons culture, media and sport select committee in its report published today (May 1).
The MPs accused Murdoch of "exhibiting wilful blindness" over the malpractice and illegal activity within his company, particularly at the News of the World, which was shut down at the height of the hacking affair last July.
In his evidence to the committee last year, Murdoch had said that his alleged lack of oversight over the News of the World and its owner News International was because it was "less than 1%" of News Corporation worldwide.
However, the MPs' report said that this "self portrayal" of a hands-off proprietor was "at odds with numerous other accounts, including those of previous editors and from [ex News International chief executive] Rebekah Brooks, who told us she spoke to Rupert Murdoch regularly and 'on average, every other day'".
The MPs added: "It was, indeed, we consider, a misleading account of his involvement and influence with his newspapers."
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Taking into account all the evidence they have gathered in the phone hacking investigation, the MPs concluded that "at all relevant times Rupert Murdoch did not take steps to become fully informed about phone hacking, he turned a blind eye and exhibited wilful blindness to what was going on in his companies and publications".
They continued: "This culture, we consider, permeated from the top throughout the organisation and speaks volumes about the lack of effective corporate governance at News Corporation and News International.
"We conclude, therefore, that Rupert Murdoch is not a fit person to exercise the stewardship of a major international company."
Not all members of the committee supported inclusion of this statement, as the Tories were against calling Murdoch "not fit" to run a global company.
Tory MP Philip Davies said at a press conference that they had seen "absolutely no evidence" to endorse such a "completely ludicrous" conclusion.
However, Labour MP Tom Watson, a vocal critic of the Murdoch empire, said that "more than any individual alive", the billionaire was to blame for phone hacking, and insisted that it was right to make that point clear.
Such a damning verdict by the MPs could have major ramifications for Murdoch, including in the US where he has faced challenges from News Corp shareholders over his leadership of the media giant.
However, the biggest headache could come in Britain, as Ofcom is currently investigating whether Murdoch and News Corp are 'fit and proper' to retain ownership of a 39.1% stake in pay-TV giant Sky.
The media regulator has said that it could revoke Sky's UK broadcasting licence if it finds evidence of wider malpractice and criminal behaviour at News Corp, effectively forcing the company to sell off the stake.
In a statement, News Corp said: "News Corporation is carefully reviewing the Select Committee's report and will respond shortly. "
Elsewhere in the report, James Murdoch - the former chairman of News International and Sky - was also found to have "exhibited wilful blindness" in the hacking affair, although he was cleared of having misled Parliament over his evidence.