Harbottle & Lewis has asked – and been refused – permission by its former client, News International, to waive client confidentially to speak out on its controversial role in the phone-hacking saga in the wake of closely-watched Parliamentary hearings this week.

The West End law firm issued a statement yesterday (19 July) following evidence presented to a Parliamentary committee by News Corporation chief Rupert Murdoch and his son James regarding alleged phone-hacking at the now-defunct tabloid the News of the World.

Harbottle was engaged in 2007 as part of an internal investigation at News International into whether phone-hacking spread further than royal editor Clive Goodman. The firm concluded that a cache of emails it reviewed did not show reasonable grounds for believing hacking went beyond Goodman.

In a statement on Tuesday evening, Harbottle said: "News International representatives referred to our advice in their statements today [19 July] before the Parliamentary select committee, both as a result of questioning and on their own account.

"We asked News International to release us from our professional duties of confidentiality in order that we could respond to any inaccurate statements or contentions and to explain events in 2007. News International declined that request, and so we are still unable to respond in any detail as to our advice or the scope of our instructions in 2007, which is a matter of great regret."

In a key exchange during the hearings, Tom Watson MP asked Rupert Murdoch what mistake he had referred to in negative comments regarding Harbottle he had made the previous week in a Wall Street Journal article.

Murdoch replied: "I think maybe that's a question for James, but there was certainly – well, we examined it, re-examined that. We found things that we immediately went to counsel with to get advice on how to present it to the police."

Subsequently, Watson asked Rupert Murdoch if he was aware that two News International executives had reviewed the emails before they were sent to Harbottle. Murdoch replied: "No."

Murdoch was later pressed on which News International staff would have been aware of Harbottle's advice. Murdoch replied: "It went to the senior officials of News Corp. Certainly the top legal officer."

James Murdoch also referred to the advice received from Harbottle in his Parliamentary testimony: "I am glad you have asked about it, actually, because it is a key bit of outside legal advice from senior counsel that was provided to the company, and the company rested on it. I think it goes some distance in explaining why it has taken a long time for new information to come out. It was one of the pillars of the environment around the place that led the company to believe that all of these things were a matter of the past and that new allegations could be denied."

There was also additional scrutiny of Harbottle's role in further Parliamentary testimony by Lord Macdonald QC, the former director of public prosecutions, who had been asked to review the emails which were recovered by News International executives earlier this year.

Macdonald had in June advised the News Corp board to hand the file over to the police after concluding it indicated "evidence of serious criminal offences".

Asked for his view on potential interpretations of the evidence he was asked to review, Macdonald told MPs: "I cannot imagine anyone looking at that file and not seeing evidence of crime on its face."

Harbottle's statement on Tuesday came after the firm on Monday (18 July) first moved to counter criticism of its role by issuing a statement arguing that it had been the victim of some inaccurate press reports, while also stressing that it was unable to correct the record due to its legal obligations.

However, in the wake of the Parliamentary hearings there have been calls from MPs for Harbottle to be called to give evidence before a select committee.

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