Former News Of The World editor Andy Coulson has gone on trial accused of lying under oath during the trial of former socialist MSP Tommy Sheridan.
Coulson, 47, a former director of communications for the Prime Minister, denies committing perjury during the 2010 case at the High Court in Glasgow.
The current trial, at the High Court in Edinburgh, formally got under way today, with the selection of the jury of nine men and six women.
The case is due to last around four weeks, with the first witness expected to be called next week.
Addressing the jury, judge Lord Burns told them there has been a "great deal of information" about Coulson, Mr Sheridan and the subject matter of the charge in the media and on the internet.
But he reminded the 15-strong panel of their oath to try the accused "solely and exclusively" upon the evidence they will hear from the witness box.
That means they must "ignore" and put out of their minds any information from any other sources, he said.
The judge said they may have formed views about Mr Sheridan or the accused "and their activities, political or otherwise".
But he added: "It would be quite wrong for you, as a jury, to be influenced in any way by such views or opinions."
The court today heard - in evidence agreed by the Crown and the defence - that, following publication of a series of articles about him in the News Of The World, Mr Sheridan raised a defamation action in Scotland's Court of Session against the newspaper's publishers, News Group International.
The jury in the subsequent 2006 defamation action decided that the politician had been defamed by the newspaper and it was ordered to pay him £200,000 in damages.
The court also heard that Mr Sheridan's perjury trial at the High Court in Glasgow was in respect of evidence he gave in the earlier defamation action.
During the 2010 trial, Mr Sheridan dismissed his lawyers and conducted his own defence. Coulson was called as a defence witness by Mr Sheridan over two days.
Prosecutors allege that Coulson, from Kent, made false claims on December 9 and 10 2010 after being sworn in as a witness.
The indictment alleges that Coulson falsely stated that before the arrest of private investigator Glenn Mulcaire and News of the World journalist Clive Goodman on August 8 2006, he did not know that Goodman was involved in phone hacking, and did so together with Mulcaire.
It claims he falsely said he did not know that payments were made to Mulcaire by Goodman and that he did not know of Mulcaire's "illegal activities".
It also alleges that Coulson said he did not have any email exchanges with Goodman in relation to Mulcaire.
The Crown further alleges that Coulson falsely stated that he did not know of Mulcaire, had not heard his name, did not know that he was employed by the News Of The World newspaper, and did not know that Nine Consultancy was Mulcaire.
It is claimed Coulson falsely said he had no knowledge of payments being made to corrupt police officers by staff of the News of the World while he was employed as an editor there.
Prosecutors allege that between October 10 2005 and August 8 2006, Coulson had heard of Mulcaire who, as well as being a private investigator, was contracted to the News Of The World.
They allege he knew that Goodman was involved in phone hacking and knew that he did so together with Mulcaire.
The three-page indictment claims that Coulson knew that Goodman made payments to Mulcaire of £500 a week until February 2006, followed by payments amounting to £4,800.
The prosecution also alleges that Coulson knew that Mulcaire was employed by the News of the World and had email exchanges about him with Goodman, in which Mulcaire was referred to as "Matey".
It is claimed Coulson knew that Nine Consultancy was the business name under which Mulcaire operated and that he knew of Mulcaire's "illegal activities" insofar as they related to phone hacking.
It is also alleged that between December 1 2002 and January 26 2007, while editor and deputy editor of the newspaper, Coulson understood that payments had been made to corrupt police officers by Goodman.
The payments included £750 in or around December 2002, £1,000 around January 2003, and £1,000 around June 2005.
These were made to procure a "green book" or other similar directories containing information including telephone numbers relating to the Royal Family and their staff, the indictment states.
Coulson pleads not guilty to the allegations against him.
The trial continues on Tuesday.