The battle of the United Kingdom’s Prince Harry with the British press is headed for a showdown with the publisher of the Daily Mirror tabloid in a courtroom in the capital London this week.

Harry, formally called the Duke of Sussex, is scheduled to testify in the High Court after his lawyer presented opening statements on Monday in the first of his legal cases to go to trial. It’s one of three alleging that tabloids unlawfully snooped on the prince in their cutthroat competition for scoops on the royal family.

The 38-year-old will be the first member of the British royal family in more than a century to testify in court, and is expected to describe his anguish and anger over being hounded by the media throughout his life, and its impact on those around him.

The younger son of King Charles 3rd has blamed the paparazzi for causing the car crash that killed his mother, Princess Diana, and said harassment and intrusion by the UK press, including allegedly racist articles, led him and his wife Meghan Markle to flee to the United States in early 2020 and leave royal life behind.

Articles he has cited date back to his 12th birthday, when the Mirror reported Harry was feeling “badly” about the divorce of his parents.

Harry said in court documents that the reports made him wonder who he could trust as he feared friends and associates were betraying him by leaking information to the newspapers. His circle of friends grew smaller, and he suffered “huge bouts of depression and paranoia.” Relationships fell apart as the women in his life — and even their family members — were “dragged into the chaos.”

He says he later discovered that the source wasn’t disloyal friends, but aggressive journalists and the private investigators they hired to eavesdrop on voicemails and track him to locations as remote as Argentina and an island off Mozambique.

Mirror Group Newspapers said it didn’t hack Harry’s phone and its articles were based on legitimate reporting techniques. The publisher admitted and apologized for hiring a private eye to dig up dirt on one of Harry’s nights out at a bar, but the resulting 2004 article headlined “Sex on the beach with Harry” is not among the 33 in question at trial.

Phone hacking that involved guessing or obtaining security codes to listen in on celebrities’ mobile phone voice messages was widespread at British tabloids in the early years of this century. It became an existential crisis for the industry after the revelation in 2011 that the News of the World had hacked the phone of a slain 13-year-old girl.

Owner Rupert Murdoch shut down the paper and several of his executives faced criminal trials.

Mirror Group has paid more than 100 million pounds ($125 million) to settle hundreds of unlawful information-gathering claims, and printed an apology to phone hacking victims in 2015. But it denies that executives — including Piers Morgan, who was editor of the Daily Mirror editor between 1995 and 2004 — knew about hacking.

The opening statements being presented on Monday mark the second phase of a trial in which Harry and three others have accused the Mirror of phone hacking and unlawful information gathering.

Two judges — including Justice Timothy Fancourt, who is overseeing the trial — are deciding whether Harry’s two other phone hacking cases will proceed to trial.