File photo. Prince Harry attended London's High Court earlier this year but was not in court on Monday. Photo: AFP
Unlawful information-gathering "acted like a web" around Prince Harry, a court has heard during his trial against Mirror Group Newspapers (MGN).
His barrister told London's High Court no aspect of his youth was safe from press intrusion - citing stories about his relationship with Chelsy Davy appearing in the Mirror.
Harry is claiming MGN journalists used unlawful methods to gather information, including phone hacking.
MGN denies phone hacking in this case.
Making his opening speech for the prince, barrister David Sherborne, who is also representing three other people, said: "These methods acted like a web around the prince in the hope it would catch the valuable information that they sought through these unlawful means, some of which made it in stories."
Among the articles complained about that are being considered by the judge are stories concerning the Duke of Sussex and his former girlfriend Chelsy Davy.
"The ups and downs and ins and outs of their relationship, the beginning, the break-ups and finally the split between them were all revealed and picked apart by the three Mirror Group titles," Sherborne continued, saying this was "clearly driven by unlawful activity".
He told the court a story published by the People in April 2005 detailed the prince's phone calls to her.
"It was as if they were never alone," he added.
Sherborne suggested the stories led to the couple's circle of friends becoming "smaller and smaller" due to them suspecting friends of leaking to newspapers, but he accepted that there is little direct evidence of unlawful methods being used to get stories like this.
Eventually the couple's relationship ended. In a witness statement previously reported, the prince claimed Ms Davy decided that "a royal life was not for her" following repeated acts of harassment.
At the heart of the case are 207 newspaper stories published between 1991 and 2011 - some 67 percent of which written about Harry.
At the start of the High Court hearing last month, the publisher of the Daily Mirror, Sunday Mirror and Sunday People admitted a private investigator had been instructed to unlawfully gather information relating to Harry's conduct in a nightclub in February 2004.
This incident does not form part of the duke's claim for breach of privacy.
David Sherborne told the court on Monday the suggestion that there was only one instance of unlawful information-gathering was "plainly implausible", arguing it would have happened on "multiple occasions".
He said "every facet" of his life was splashed across the papers and it would have been "obvious" stories about his private life were driving sales for MGN.
But Andrew Green KC, representing MGN, said there was no evidence to support claims by the prince.
Summarising MGN's defence, Green said there was no data showing that Harry had been hacked, "still less on a habitual basis".
Green said none of the whistle-blowing journalists who have come forward admitting phone hacking said they had hacked the prince's phone.
"There's no evidence to support a finding that any mobile phone owned or used by the Duke of Sussex was hacked. Zilch, Zero, Nil, De Nada, Niente, Nothing," he said.
Judge 'surprised' Harry not at court
Earlier, the judge in the case, Mr Justice Fancourt, said he was a "little surprised" to hear the duke would not be attending court on Monday.
He had given an earlier direction that witnesses should be available on the first day of their individual case in case there was time to give evidence.
Green, for MGN, accused the prince's side of "wasting time", saying it was "absolutely extraordinary we were told just last week that he is not available for day one of his own trial".
Sherborne said Harry had flown in from Los Angeles after his daughter's birthday, and added: "He is in a different category from the three other claimants due to his travel and security arrangements."
The Duke of Sussex is likely to begin giving evidence on Tuesday, his lawyers said, making him the first senior royal in 130 years to testify in court.
Nearly half of the public section of the court emptied after confirmation he would not be appearing on Monday.
Alongside the duke, Coronation Street actors Michael Turner - known professionally as Michael Le Vell - and Nikki Sanderson, as well as Fiona Wightman, the ex-wife of the comedian Paul Whitehouse, have also brought claims against the publisher.
The claimants argue senior executives must have known about unlawful information gathering behind these stories and failed to stop it, which MGN denies.