Andy Coulson had his phone hacked by the investigator employed by the News of the World to listen to the voicemails of public figures, the trial heard.

The QC representing the former editor of the now defunct tabloid told jurors yesterday they should be aware that Glenn Mulcaire had delved into Mr Coulson's own messages.

Timothy Langdale told the trial at the Old Bailey that the prosecution may not have told them because it was "hard to reconcile" with the case they were attempting to make against the former Downing Street communications chief.

In a rare opening statement so early in a trial, Mr Langdale QC said: "When it is alleged that Mr Coulson must have known (about phone hacking), if only on the basis that each of the news editors was party to hacking, you may like to bear in mind that Mr Coulson himself was hacked by Glenn Mulcaire.

"The CPS did not choose to tell you about that. It is not easy to reconcile with their case, is it?

"Both conspirator and victim? It is fair to say, is it not, that the two things do not sit easily together?"

Mr Langdale suggested that jurors should keep an open mind. He said later in the trial the former editor would claim the prosecution case against him was wrong.

He said it was "relatively unusual" for a defence barrister to make an opening statement to the court, but that there were good reasons for doing so.

He added: "We invite you to bear in mind that what you have heard so far is, perhaps obviously... just one side of the story. It will be some two months or so before you hear the defence for Mr Coulson present his case.

"This case has as you know an unusual history. It's now being heard in a court of law after years of coverage of one kind or another in both the international and national media.

"You will be hearing from Mr Coulson in due course. We invite you to keep an open mind in all these matters.

"You will draw your own conclusions when you have heard all the evidence.

"The prosecution has a lot to say about Mr Coulson and it's our case that a lot of it is wrong."

Mr Coulson resigned as editor after former colleague Clive Goodman and Mulcaire were jailed for conspiring to hack phones in 2007.

Mr Langdale said: "He will tell you what happened when he was deputy editor of the News of the World (NotW) and then editor.

"Certainly something went badly wrong at the NotW during his watch."