Former News of the World investigations editor Mazher Mahmood and chief reporter Neville Thurlbeck appeared today before the Lord Leveson inquiry into press standards. The inquiry was launched following the phone hacking inquiry, which led to the closure of the 168-year-old Sunday tabloid in July.
Mahmood, who now works for the Sunday Times, said that all his newspaper investigations were "totally justified".
Thurlbeck, who was fired by News of the World publisher News International after being arrested on suspicion of phone hacking, said front page "splashes" on the private lives of public figures such as David Beckham and Max Mosley were published in the public interest.
Mahmood is best known for the "fake sheikh" undercover sting at the News of the World, which resulted in three Pakistan Test cricketers and a corrupt sports agent being sent to prison in November on charges of match-fixing.
Giving evidence off-camera to protect his identity as an investigative journalist, he said that there was a "regulated" process at both the News of the World and Sunday Times in regards to getting his undercover investigations commissioned.
He said that he had to ensure that the source of the story was credible, and that the public interest justified the subterfuge involved in the investigation.
"Everything was discussed with the legal team. I couldn't go off piste. Throughout the investigation I remained in touch with our lawyers," said Mahmood, whose work over the years has led to 261 "successful criminal prosecutions".
However, Mahmood admitted that the Sunday Times had processes that were "a lot more stringent and more formalised" than the News of the World.
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Asked what were the main reasons for justifying a story, Mahmood said that "if criminality was factor, there was moral wrongdoing, or hypocrisy".
"Each case was on its own merits. If you had an MP who was cheating on his wife, then clearly there was a public interest," he added.
Mahmood said that he had written about 500 stories for the News of the World, and only "a small fraction" involved celebrities. He also insisted that he had "never entrapped people".
Asked about the public interest in the Anderton case, Mahmood said: "She was not just taking drugs, she was selling drugs and she was involved in prostitution. There was clear criminality."
He said that the News of the World spent a fortune on the story. Both situations involved using escort agencies, including the Miss X case involving a reported $60,000 fee, and so Mahmood did not "entrap" the women with offers of cash, he merely responded to prices set by the agency.
"It's quite annoying this myth of entrapment," he told the inquiry. "We never entrap people and frankly I don't think you can entrap people in the way they suggest."
Pressed on the public interest in cases such as Anderton and Miss X, Mahmood said it was about exposing double standards in the public image.
"If they are posing in Hello magazine playing happy families, but then working as a prostitute, there is a clear moral ground in exposing them. In my view," he said.
However, Mahmood stressed that his main responsibility was to write stories, adding: 'I'm not a police officer, I'm not a social worker, I'm a journalist.'
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Elsewhere in his evidence, Mahmood insisted that he had never paid or commissioned a private investigator for his stories, but he admitted that Derek Webb - who carried out surveillance work for the News of the World - had been assigned to work with him by the paper's newsdesk.
Mahmood also said that the first time he was aware of phone hacking at the paper was after the arrest of former royal editor Clive Goodman in 2007.
He said that hacking soon became the talk of the office, and claimed that "all the fingers were pointing towards the newsdesk".
Thurlbeck also gave evidence today, but was not asked any questions on phone hacking as Lord Leveson did not want to "prejudice any criminal inquiry".
The former chief reporter said that someone selling a "kiss and tell" story would typically be paid around £15,000, but claimed that former News of the World editor Colin Myler was "fastidious" in ensuring all stories were in the public interest.
He said that the paper decided to run a front page article on David Beckham's alleged extra-marital affair with Rebecca Loos because it was the decided that there was public interest as "the Beckhams had been using their marriage to endorse products".
Thurlbeck said that he had spent five months working on the story, including six weeks in Australia, and five or six weeks in Spain, and revealed that Loos had been paid "a six figure sum - just" for her involvement.
Discussing an infamous News of the World article which falsely claimed that ex-motorsport president Max Mosley had engaged in a "Nazi-themed" orgy, Thurlbeck said that the supposed Nazi connotations initially persuaded the paper of public interest.
Mosley won £60,000 in damages from the News of the World in 2008 after a judge ruled that the story had invaded his privacy.
But Thurlbeck today defended the story, saying: ''I think we got the facts correct. The facts are indisputable."
Thurlbeck's involvement in the hacking affair has been under close scrutiny ever since details emerged of a crucial email headed "for Neville", which contained transcripts of messages illegally intercepted from the phone of PFA chief executive Gordon Taylor.
The email, which was sent in 2005 but only surfaced in April 2008, appeared to debunk News International's repeated assertion that hacking was only down to one "rogue reporter" at the News of the World.
However, a letter was published from Thurlbeck to the Commons culture media and sport select committee last week in which the reporter accused the News of the World of "withholding evidence" in the investigation into phone hacking.
Thurlbeck claimed that he had found evidence that exonerated him of any blame in the hacking of Taylor's phone, but said that this had been buried by bosses at the paper.
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