Tom Watson, the MP central to chasing down the phone hacking inquiry, has described new evidence against News Of The World as "devastating".
On Tuesday, documents showing how the News of the World tried to keep the phone hacking case under wraps were published by the parliamentary committee investigating the scandal.
Correspondence between the tabloid's then legal chief Tom Crone and editor Colin Myler details their efforts to achieve a "confidential settlement" with the chief executive of the Professional Footballers' Association Gordon Taylor.
In a memo on May 24 2008, Mr Crone advised: "Our position is very perilous."
Now Watson, who will be on the committee when James Murdoch reappears on 10 November, said: "This is devastating for News International. The fact that this new evidence has come out really changes a lot of things.
"It also goes to show that James Murdoch still has a lot of questions to answer when he appears at the committee."
The new evidence showed how Taylor had obtained a "damning email" containing transcripts of his private voicemails as well as evidence from the Information Commissioner of other illegal activities by News of the World journalists, Crone said.
"Amongst the documents from the Information Commissioner is a list of named News of the World journalists and a detailed table of Data Protection infringements between 2001 and 2003 (this is based upon evidence seized in a raid on another private investigator who was subsequently prosecuted).
"A number of those names are still with us and some of them have moved to prominent positions on NoW and The Sun. Typical infringements are 'turning around' car reg and mobile phone numbers (illegal)."
In a subsequent email to solicitor Julian Pike, Crone says that Myler was to use the memo "as the basis for his chat with Chief Exec James Murdoch" - suggesting that Murdoch was made aware of the issues at that stage.
Mr Murdoch, who is to appear before the Culture, Media and Sport Select Committee for a second time in November, has said he did not recall being briefed about the Gordon Taylor case until 10 June 2008.
Also published are the notes of the News of the World's external solicitor, Julian Pike, from a phone call with Mr Myler on 27 May 2008 in which he writes that the editor "spoke to James Murdoch".
The documentation, provided by Mr Pike's firm Farrer & Co, shows how the News of the World tried to negotiate a settlement with Mr Taylor that would keep the case out of the courts.