REBEKAH Brooks and Andy Coulson had an affair that lasted for six years and went on at the time that phone hacking was being carried out at the News of the World, an Old Bailey trial heard today.
A jury was given details of an intimate letter found on Brooks's private computer in which she talked of her love for the close colleague who would go on to become David Cameron's Director of Communications at Downing Street.
"The fact is you are my best friend, I tell you everything, I confide in you, I seek your advice, I love you, care about you, worry about you. We laugh and cry together," wrote Brooks.
"In fact, without our relationship in my life I'm really not sure how I would cope."
The letter, which was discovered during a police investigation in 2011, was written in February 2004, was written after Coulson had indicated he wished to end the affair, the court heard.
Addressing the potential end to the relationship, Brooks went on: "The thought of finding out anything about you or your life from anyone else fills me with absolute dread."
In the letter Brooks talked of "the rules" by which the pair kept their relationship secret. She also discussed Coulson's position with "KRM" (a reference to Rupert Murdoch, the court was told), saying "you must not brood on lack of calls".
Explaining why he was revealing the contents of the letter Andrew Edis QC, for the prosecution, said: "Throughout the relevant period, what Mr Coulson knew, Mrs Brooks knew too, and what Mrs Brooks knew Mr Coulson knew too. That's the point because it's clear from that letter that as of February 2004 they had been having an affair which had lasted at least six years."
Earlier Mr Edis said that Brooks had claimed she had "never heard" of a private investigator who was earning £92,000 a year from the News of the World while she was editor, "until he was arrested" for phone hacking, a jury at the Old Bailey heard today.
The News of the World phone hacking trial was told that the newspaper under Brooks's editorship operated under strict budgetary constraints and it was inconceivable that the senior management was unaware of Mulcaire's activities.
"They must have known what it was for or they would never have allowed it," Andrew Edis QC, for the prosecution told the court.
The jury was informed of emails from Brooks in which she berated staff for overspending. "In the current economic climate we have to stick to these targets," she said in one email.
In another she stated: "Going over budget will not be accepted. It's a disciplinary situation. How can I make myself any more clear?"
Mr Edis told the court that Mulcaire - who he said was an ex-footballer who had the nickname "Trigger" - had a "special arrangement" for payments, which fell outside the paper's usual strict rules for using freelances.
The chief prosecuting counsel said Stuart Kuttner, the managing editor of the News of the World, had personally signed off 221 separate payments to Mulcaire worth a total of £413,527, which he said was 72 per cent of the total money received by the investigator from the newspaper.
"Do you think he signed off that £413,527 because he knew what it was for and he thought it was worth it, which is our case?"
The jury was also told of an email from Mr Kuttner in which he warned of cutbacks, saying that the "balmy days of indulgence are over".
Mr Edis said: "That's the climate which we say generates the inference that they must have known what they were spending on Mr Mulcaire. The money was going out of the paper. Where was it going, did they care? Yes they did, and these emails show it," he said.
Mr Edis said Ms Brooks had claimed to have never heard of Mr Mulcaire until he was arrested over phone hacking in 2006.
This was in spite of a 2002 NotW article under her editorship - shown to the jury - in which Mr Mulcaire was described as being "part of the News of the World's special investigations team".
Mr Edis said: "This paper only comes out once a week, you might expect the editor to read it."
The jury was also told how Andy Coulson, who was Brooks's deputy before succeeding her as editor in 2003, had increased Mulcaire's payments to £2,019 a week (a rise from the £1,769.23 a week he was receiving when Brooks was editor).
But the court was told that Coulson became unhappy with the newspaper's output and sent an email to staff warning that they were failing to match the "unprecedented success" the paper enjoyed in 2004.
"The truth is we've not fulfilled our brief this year," he told senior staff in one email. "I'm not for a moment doubting your efforts but we need a hit. Badly."
Mr Edis said: "You are going to have to form a view about how much pressure there was on the journalists at the News of the World."
He said that former England manager Sven Goran Eriksson and former Home Secretary David Blunkett, the subjects of two notable stories cited by Coulson in the email, had both been victims of phone-hacking.
Earlier, the jury was played a tape recording of Mulcaire calling a phone company for information which prosecutors alleged he used for unlawfully accessing voicemails.
The court heard Mulcaire, who was said to be part of the "investigations unit" at the News of the World, calling a woman at O2 in order to obtain pin codes of people he was intending to target.
"He knows the right things to say, he's chatty, engaging and she she doesn't seem troubled," Mr Edis told the jury.
"The fact of the matter is that in those days it was perfectly possible it seems for someone like Mr Mulcaire to get the information that he needed in order to hack phones."
The prosecution's case is that Mr Mulcaire's hacking was part of a conspiracy to intercept communications that involved Brooks, Coulson and Kuttner.
Mulcaire was on a "big contract", Mr Edis told the court. "A contract like that, a big contract, involves the senior management - in this case the editor, the deputy editor and the managing editor. The three defendants you have to try for phone hacking."
The jury was shown a series of emails between Mr Mulcaire and Ian Edmondson, a former news editor of the News of the World who is also alleged to have been part of the phone hacking conspiracy.
Mr Edis alleged that email correspondence between the two was evidence of the hacking of the phone of the former Government minister Tessa Jowell.
One message from Mulcaire to Edmondson said: "Substantial traffic both ways. Also looks like she's selling up."
The prosecution said that the interest in Ms Jowell coincided with stories linking her partner David Mills to a bribery scandal in Italy. Mr Edis said that although this was a "proper news story", the alleged actions of the News of the World were inexcusable.
"This is phone hacking and it's a crime," he said. "There's no justification for committing this criminal offence in pursuit of a story."
On invoices submitted to the News of the World by Mulcaire, the work was described with the words "Jowell assist". Mr Edis said: "We know what he did."
He said: "The prosecution say these documents are evidence against all the conspirators actually because although they are mr Mulcaire's documents he's creating the documents as an essential part of him working out the conspiracy, doing his part of the phone hacking and reporting his results to Mr Edmondson, so that he, Mr Edmondson, can do some phone hacking of his own."
The court was told that some phone hacking had occurred from the premises of News International, publishers of the News of the World.
The jury was also given details of emails relating to Joan Hammell, an adviser to Lord Prescott. "There's 45 messages," Mulcaire told the news editor.
Mr Edis asked the jury: "Do you think it's likely or even possible that Mr Edmondson didn't know what was being done by Mr Mulcaire?"
He also alleged that Edmondson had been at the centre of a planned "spoiler" exercise against its Sunday rival the Mail on Sunday "by hacking other journalists", named as Dennis Rice and Sebastian Hamilton.
All of the eight defendants in the trial deny the charges against them.
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