Repeat sex offender David Robert Nicholson stared blankly into space in the High Court at Auckland yesterday as he was sentenced to eight years' jail.

The Mt Wellington resident was convicted earlier this year on three counts of sexually violating a 17-year-old boy while working as a tutor at an Auckland training institute.

Justice Glazebrook said the 46-year-old, who has several previous convictions for attacks on young boys, had shown a lack of "true remorse" and refused to take full responsibility for his actions.

He had deliberately befriended the "shy, gentle-natured" teenager, wooing him to his house with new clothes and food, before sexually violating him. The victim, now aged 18, did not flee the house for fear that Nicholson would jeopardise his chances of getting into the Army.

Justice Glazebrook said the teenager had suffered serious emotional damage from the incident, including nightmares and flashbacks.

Nicholson's lawyer, Marie Dyhrberg, continued to argue yesterday that the sex was consensual because the boy did not say "no" to Nicholson's advances.

Nicholson has already served two jail terms for sex offences involving boys. He was sentenced to 18 months for attacking a 15-year-old in 1995 and earlier served a 10-month term for indecent acts on other boys.