The private detective at the centre of the News of the World phone hacking scandal acted "on the instructions of others", his legal team have said.
Glenn Mulcaire's lawyers strongly rejected suggestions that he "unilaterally" hacked into voicemails of victims without the newspaper's knowledge.
The statement came as the Tory MP John Whittingdale, chairman of the Commons Culture, Media and Sport select committee, said James Murdoch could be recalled to Parliament after two senior executives at the newspaper claimed he knew about the prevalence of phone-hacking back in 2008.
In a firmly worded statement, Mr Mulcaire's lawyers said he was "effectively employed" by the paper from 2002. He was subsequently jailed along with former News of the World royal editor Clive Goodman in January 2007.
Repeating Mr Mulcaire's apology for his part in the scandal, his lawyers added: "As an employee he acted on the instructions of others.
"There were also occasions when he understood his instructions were from those who genuinely wished to assist in solving crimes.
"Any suggestion that he acted in such matters unilaterally is untrue. In the light of the ongoing police investigation, he cannot say any more."
Mulcaire has found himself facing questions over the extent of his involvement in the saga following fresh allegations that the former Sunday tabloid illegally accessed the voicemails of murdered schoolgirl Milly Dowler, relatives of victims of the 7/7 bombings in London, and grieving military families.
MPs focused their attention on an email containing the transcripts of hacked voicemails and headed 'For Neville', apparently a reference to the News of the World's former chief reporter Neville Thurlbeck.
James Murdoch told Mr Whittingdale's committee last week that he was unaware of the email and News Corp has always insisted that it learned the problem was not confined to a single "rogue" reporter only when papers were lodged in a civil court by the actress Sienna Miller late last year.
But following Mr Murdoch's testimony in front of MPs, the former News of the World editor Colin Myler and its legal manager Tom Crone said the head of News Corp in Europe and Asia was "mistaken".
They insisted they had informed him of the email when he signed off a reported £700,000 out-of-court settlement with Gordon Taylor, the chief executive of the Professional Footballers' Association, in 2008.
Yesterday Labour MP Tom Watson, who has led the phone-hacking campaign, said he had asked for Mr Murdoch to be recalled immediately but he had been voted down by his colleagues on the committee.
Meanwhile, it was revealed last night on Twitter that the Metropolitan Police will be formally investigating the allegation that ex-British intelligence officer Ian Hurst had his computer hacked into in 2006.
It is believed Mr Hurst was targeted as he had worked in British Army intelligence running IRA informers in Northern Ireland.