Marius Borg Hoiby, 29, who joined the royal family when his mother Mette-Marit married Crown Prince Haakon in 2001, has pleaded not guilty to the most severe accusations against him, including those of rape, while admitting to some lesser charges.
The seven-week trial, which is due to end on Thursday, has transfixed the Nordic country, detailing Hoiby's drug addiction, self-made videos of sexual encounters and more than 800 electronic messages entered into evidence.
The trial coincided with Crown Princess Mette-Marit's apology for "poor judgment" in maintaining contact with the late US sex offender Jeffrey Epstein after he was convicted in 2008.
Both events have hurt the overall popularity of the monarchy, according to opinion polls.
Lead prosecutor Sturla Henriksboe on Wednesday set out the sentence he was seeking for the 40 charges against Hoiby, which included several counts of rape which investigators said happened when the alleged victims were sleeping or unconscious.
Hoiby pleaded guilty at the start of the trial to charges that carry lighter sentences, including offensive sexual behaviour, driving too fast and driving without a valid licence.
Henriksboe told the court that Hoiby must be treated like any other Norwegian, facing neither tougher nor milder punishment for being part of the Nordic nation's most prominent family.
But in tearful testimony last week, Hoiby said heavy media coverage of his trial had made him "an object of hatred" and portrayed him as a monster, leading to anxiety and clinical depression.
"Hoiby is no monster. None of us are," Henriksboe said at the beginning of his closing argument on Monday. "He must not be sentenced for who he is, but for what he did."
The trial, which began in early February, has shocked Norway and drawn global media attention.
with Reuters
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