By Martin HickmanThe Sun did not rely on phone hacking to establish the identity of Home Secretary David Blunkett's lover, the Old Bailey heard today.Kimberly Quinn was named by the redtop as being Mr Blunkett's partner on Monday 16 April 2004, the day after its Sunday sister the News of the World broke the news of the affair between the Labour politician and the married woman.The exclusive had come from the News of the World's interception of messages left by Mr Blunkett on Mrs Quinn's phone.Phone records show frequent calls and texts between the then Sun editor, Rebekah Brooks, and her on-off boyfriend and editor of the NoW, Andy Coulson, in the days before the story broke on Sunday 15 April.Asked by her counsel Jonathan Laidlaw QC how the Sun learnt of Mrs Quinn's identity, Mrs Brooks said that although she could not discuss sources, she and her news and political reporters worked out the woman was Kimberly Quinn.Mr Coulson had however tipped her off about the fact that the NoW was running a story about Mr Blunkett on Saturday 14 April, on the eve of publication.Mrs Brooks said: "I think, without going into sources, from memory, what happened: I was told by Andy that the News of the World had got this, my political team and I and the news team - once we had seen that the News of the World hadn't named her - we would have gone full steam ahead."She added: "I remember it became quite obvious David Blunkett and Kimberly Quinn wasn't as secret as initially thought, and a brief search of cuttings showed that there had been a couple of items about them attending a public event together."She went on: "I think there were lots of different rumours but her name came up. I think it was a case of getting one of his [Blunkett's] special advisers to confirm it to me."Mrs Brooks also denied discussing phone hacking with the wife of golfer Colin Montgomerie at a lunch with mutual friends on 20 September 2005.In her evidence, Eimear Cook claimed that Mrs Brooks had told her that she could not believe that wealthy and famous people with PAs had not changed their voicemail PIN codes.Mrs Brooks told the Old Bailey: "It just doesn't sound like the kind of thing I would have said. I did know way back when there was a certain flaw with voicemail settings back in the late 90s... I don't know why I would have brought that up with Mrs Cook.She also disputed Mrs Cook's suggestion that she had been laughing as she discussed her overnight detention in connection with a domestic incident against her then husband Ross Kemp.Asked by Mr Laidlaw: "Is there any truth in you speaking about this matter?," Mrs Brooks replied: "None whatsoever.""At the time what happened wasn't funny. It was the end of the marriage. I was a terrible incident in my life, being thrown in prison."Then [rather than the her arrest and questioning over hacking in 2011] it was the first time and it was a shock. When I read [Mrs Cook's witness statement], I thought: 'Gosh, I would never be laughing about that."Mrs Brooks, who edited the News of the Wold between 2000 and 2003 and the Sun between 2003 and 2009, and Mr Coulson, who edited the NoW between 2003 and 2007, deny conspiring to hack phones. The trial continues.