Prince Harry was in a London court on Monday as the lawyer for a group of British tabloids prepared to ask a judge to toss out lawsuits by the prince, Elton John and several other celebrities who allege phone tapping and other invasions of privacy.

The hearing involves one of several lawsuits Harry, also known as the Duke of Sussex, has brought against the media. It is expected to last four days.

Harry's presence at the High Court in London is a sign of the importance he places on the case.

Associated Newspapers, which publishes titles including the Daily Mail, is asking the High Court to end claims brought by a collection of high-profile individuals who are seeking damages for misuse of private information. Other plaintiffs include John’s husband, David Furnish, and actresses Liz Hurley and Sadie Frost.