The never-ending demand for royal stories at Rupert Murdoch's British tabloids led employees to hack voicemail messages left by the princes, target senior aides and pay thousands of pounds for a photo of Prince William in a bikini, prosecutor Andrew Edis said.
Journalists at Murdoch's News of the World routinely used phone hacking to back up tips and find evidence for stories, he said — using a "perfectly rational but entirely illegal system."
In three days of opening statements, Edis has taken the jury at London's Central Criminal Court on a methodical journey through the "dog-eat-dog" tabloid battle for scoops.
Former News of the World editors Rebekah Brooks and Andy Coulson, both 45; Brooks' husband Charles and five former staff of Murdoch's British newspapers are on trial in the first major criminal case spawned by the revelation in 2011 that employees of the tabloid eavesdropped on the voice mails of celebrities, politicians, top athletes and even crime victims.
The eight defendants deny a variety of allegations related to phone hacking, bribing officials and obstructing a police inquiry.
Coulson and Brooks have said they were not aware that hacking was going on when they were in charge of the News of the World — she from 2000 to 2003 and he between 2003 and 2007.
But prosecutors say they and other senior staff must have known that illegal activity was taking place at the popular paper.
Edis said one email from Coulson to a subordinate, referring to hacking target Calum Best — a minor celebrity and son of the late soccer star George Best — contained the instruction: "Do his phone."
Other targets, the prosecutor said, included actors Jude Law and Sienna Miller; Paul McCartney and his then-wife, Heather Mills; politicians Tessa Jowell, John Prescott and David Blunkett; and aides to royals William and Harry.
One message left by Harry for his private secretary asking for help on an essay while he was a cadet at Sandhurst military academy in 2005 was hacked by Glenn Mulcaire, a private eye working for the News of the World.
In the transcript, Harry asked for information on a 1980 siege at the Iranian embassy in London, "because I need to write an essay quite quickly on that but I need some extra info. Please, please email it to me or text me."
The resulting News of the World story was headlined "Harry's aide helps out on Sandhurst exams."
Royal exclusives were a News of the World specialty during Coulson's tenure. Edis said he was "a very hands-on editor ... interested in getting good, exclusive royal stories."
Coulson is charged, in addition to phone hacking, with agreeing to pay palace police officers for two private royal phone directories. Some of the numbers in the phone books were then hacked, Edis said.
Prosecutors say Brooks, too, was hands-on, both at the News of the World and at The Sun, which she edited between 2003 and 2009. Among the charges against her is that she paid a member of the armed forces and a senior defence official tens of thousands of pounds for stories — including a 4,000-pound payment for a picture of William "dressed as a Bond girl" in a bikini, the prosecutor said.
Friends and families of celebrities were targeted, Edis said, and sometimes people were even caught up at random. A hairdresser named Laura Rooney was hacked "because they thought she was related to Wayne Rooney," the Manchester United soccer star. She wasn't.
Private eye Mulcaire and News of the World royal editor Clive Goodman were both briefly jailed in 2007 for hacking the phones of William and Harry's aides, but Murdoch's company insisted the law-breaking had been limited to the pair.
That claim dissolved when a rival newspaper reported in 2011 that the News of the World had eavesdropped on the phone of Milly Dowler, a 13-year-old kidnapped in 2002 and later found murdered.
The public outcry led Murdoch to shut down the 168-year-old paper and pay out millions in compensation to hacking victims. It also spawned criminal investigations in which dozens of journalists and officials have been arrested.
It has heaped pressure on Britain's freewheeling press — and on Prime Minister David Cameron, who had close ties to both Brooks, his friend, and Coulson, his communications chief between 2007 and 2011.
The trial's bombshell revelation so far has been that Brooks and Coulson had a secret affair lasting at least six years and covering much of the alleged hacking time period.
Jill Lawless can be reached at http://Twitter.com/JillLawless