A former News of the World reporter is due to be sentenced for phone hacking after giving key evidence in the case against his old boss, Andy Coulson.
Dan Evans last year admitted accessing the voicemails of celebrities including James Bond actor Daniel Craig and supermodel Kate Moss while he was working at the Sunday Mirror and after he was recruited by the NotW.
The 38-year-old became the star prosecution witness in the Old Bailey hacking trial of former No 10 spin doctor Coulson, who earlier this month was found guilty of the hacking plot and jailed for 18 months.
Evans told the court that he played the NotW editor a voicemail from actress Sienna Miller to Craig suggesting they were romantically involved while she was still dating Jude Law in 2005.
He also gave evidence that "even the office cat" knew what was going on at the NotW before it was shut down over the scandal in 2011.
Despite the conviction of NotW royal editor Clive Goodman and private detective Glenn Mulcaire in 2006, Evans was found out in 2009 when designer Kelly Hoppen, Ms Miller's ex-stepmother, caught him hacking her phone.
When he was arrested in August 2011, he produced a prepared statement for police in which he initially blamed "sticky keys" on his Nokia phone.
But he admitted during the hacking trial that that explanation was "cobblers" and he had just been "maintaining the lie".
He later decided to come clean about hacking so he could "look his children in the eye", the court heard.
Evans, of Kilburn, north London, has admitted two counts of conspiring to hack phones - one when he worked at the Sunday Mirror between 2003 and 2005 and the other from 2004 to 2010 at the NotW.
He has also pleaded guilty to conspiring to commit misconduct in a public office between 2008 and 2010 and perverting the course of justice between 2009 and 2010 by making a false witness statement in the High Court.
He will be sentenced by Mr Justice Saunders at the Old Bailey.