Prince Harry has arrived at a London court ahead of his testimony against a tabloid publisher he accuses of phone hacking and other unlawful snooping.

The prince arrived at the High Court in a black SUV.

Harry has made a mission of holding the U.K. press to account for what he sees as its hounding of him and his family.

This is the first of several lawsuits to go to trial. He accuses the publisher of the Daily Mirror of using unlawful techniques on an “industrial scale” to get scoops.

The 38-year-old son of King Charles III will be the first British royal since the 19th century to enter a courtroom witness box. He will face cross-examination by a lawyer for the defendant, Mirror Group Newspapers.

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The Associated Press contributed to this article.