PM rebuked over 'premature and ill-advised' comments on his former spin doctor

Andy Coulson had already been found guilty of phone hacking and faced two further charges when he arrived at court today, but his legal team argued that he could not get justice after the Prime Minister made a televised public apology for employing Mr Coulson as his No. 10 spin doctor.

"I gave him employment on the terms of the assurances he gave me," the Prime Minister said. "They turn out not to be right."

Read: Cameron's problem was not asking enough questions

However, Mr Cameron's statement that his former PR adviser had lied to him came as the jury was still considering the outstanding charges against the former News of the World editor of conspiring to commit misconduct in a public office by paying police officers for two royal directories.

Mr Coulson's barrister described the Prime Minister's comments as "astonishing and unprecedented...at such a critical juncture."

Watch: PMQs - Cameron faces questions on Coulson

The trial judge, Mr Justice Saunders confirmed that the Prime Minister's intervention could have "wrecked" the trial.

He told the jury they should ignore all comments they had heard and gave them an extra hour to deliberate, before accepting they would not be able to reach verdicts against Mr Coulson and former News of the World Royal Editor Clive Goodson.

During Prime Minister's Questions today, Mr Cameron apologised once again for employing Mr Coulson.

More: Hacking jury discharged after failure to reach verdicts

However, Labour leader Ed Miliband was dogged in his criticism of the Prime Minister during the session.

At one stage he accused Mr Cameron of bringing "disgrace" on Number 10 by employing Mr Coulson.

The family of murdered schoolgirl Milly Dowler - whose phone the former tabloid hacked after her disappearance in 2002 - called for the Government to never let such practices happen again

More: PM faces questions over Andy Coulson appointment

Milly's sister Gemma said in a video message:"Ordinary people have suffered terribly from journalists who recklessly intruded into private grief and stole private information."

Graham Foulkes, whose son David died during the July 7 bombings, was told by police that the 22-year-old's phone may have been hacked by journalists.

More: Rebekah Brooks cleared of all charges in phone hacking trial

He told ITV News his family "left some very personal and very emotional messages" on the answerphone of David's mobile during the days that he was missing and called such phone hacking "an horrendous crime" and "unbelievably wicked".

Mr Coulson will return to court next week to be sentenced for hacking and will find out then whether he faces a retrial on those charges the jury could not reach a verdict on.

Read: CPS: Hacking trial was to 'explore culture of invading privacy'