Simon Hughes says police had evidence seeming to indicate 'at least three' NoW staff asked Mulcaire to access his voicemail

Scotland Yard failed to tell a senior Liberal Democrat MP for five years that police had evidence in their possession that appeared to indicate that "at least three" News of the World journalists were involved in commissioning the hacking of his phones by a private investigator.

Notes seized by the Metropolitan police from the home of Glenn Mulcaire in 2006 contained detailed information about Simon Hughes's telephone numbers and the names of three journalists in the margins of the notes, referring to reporters who are thought to have commissioned the investigator's hacking work.

However, giving evidence to the Leveson inquiry, Hughes said he was never shown any of Mulcaire's notes about him when he was told by police his phone messages had been intercepted in October 2006. He was only shown the notes by police at a meeting on May 25 2011, and was "shocked" at the level of personal detail they contained.

Back in 2006, the police were preparing a case against the News of the World's royal editor Clive Goodman and Mulcaire, both of whom were sentenced to jail for phone hacking-related offences in January 2007.

"I find it impossible to find a good explanation for why that happened," said Hughes who said there had been "significant failure" on the part of the police. When Hughes asked detectives in 2006 whether other journalists were involved in phone hacking, he was told that the investigation was not proceeding against anybody else.

The MP added in his written statement: "I suspect that the police had shut down this investigation, much to the delight of News Group (publishers of the News of the World), and ignored evidence of long-standing and widespread criminality. I do not know of any good or persuasive reason why this should be, and it makes me extremely suspicious."

Hughes was one of a group of five non-royal phone-hacking victims to be selected to support the police case in the Mulcaire and Goodman trial but said it wasn't until he was approached by police last year that he discovered the extent of evidence against the News of the World. Others included PR man Max Clifford and Gordon Taylor, chief of the Professional Footballers' Association.

"There was no prosecution against anybody other than Clive Goodman, and Clive Goodman only because of his work with the royal family, whereas there was a whole range of people clearly acting in concert, either directly or indirectly, illegally, and they were not touched," he said.

Hughes told Leveson he was "surprised and disappointed" that only two people were taken to court not just because there were three people allegedly involved in ordering phone hacking apart from Clive Goodman, but that there was also evidence from Mulcaire's notes that there were hundreds of victims outside the handful the police were using in the trial in 2006.

"Clearly employees were engaged, and therefore the whole panoply of other people, who it now appears had their voicemails hacked on the instructions of people in News of the World, were not in any way used as evidence against the employees," he added.

Hughes also told Leveson that Goodman and Mulcaire were tried on the basis that the private investigator had received £12,300 for his services. But it now appears the police had evidence that Mulcaire could have received up to £1m. This figure emerged at the Leveson inquiry on Monday and is far higher than previous information on Mulcaire's earnings from his alleged phone hacking and blagging activities.

It emerged last week from evidence disclosed after an application from the Guardian that Mulcaire earned about £100,000 a year between 2001 and 2006.

Today Hughes disclosed a new table of alleged payments to Mulcaire which show he may have earned anything from £775,786 to £849,470 from News International between 1999 and 2007 – far more than was disclosed to the court at the time of Mulcaire's trial.

"The court sentenced Goodman and Mulcaire on the basis that £12,300 was the known transaction payment. It is clear from here and clear, as counsel knows, from other evidence, that there was at least £500,000 of certain payment by News of the World to Mulcaire," Hughes told Leveson.

The Lib Dem MP said Mulcaire's notebooks showed that the News of the World had tried to stand up stories about a man and a woman linked to him "based on a salacious assumption".

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