As police have placed him on remand for four weeks, he begins the trial in custody.
His defence team intends to appeal against the decision.
The crown princess is facing increasing criticism after it emerged that she was cited in hundreds of emails showing extensive contacts with the late sex offender Jeffrey Epstein. She has admitted showing “poor judgement”, but the fallout has already begun, with one organisation dropping her as patron for its annual prize.
Heavy court restrictions have been imposed on the trial, with a ban on any pictures of Marius Borg Høiby inside or outside court. There is also a ban on any detail that might identify the four women who he is alleged to have raped.
The royal family will not attend any of the proceedings in Courtroom 250 at Oslo district court, where the trial has attracted enormous interest throughout Norway and beyond.
Commentators do not see that as particularly surprising, with King Harald V and Queen Sonja heading to the Winter Olympics in Italy later this week, but it adds to a sense of isolation surrounding Crown Prince Haakon’s stepson.
Marius Borg Høiby was born four years before Mette-Marit married the crown prince, and although he is seen as a close member of the family he is not part of the royal family itself and not a public figure.
