A 19-year-old has been jailed for three years for having sex with a teenage girl in circumstances that were described by the Crown as "very close to rape".

Christchurch District Court Judge Colin Doherty referred to a "chilling conclusion" from Murray James Allan's pre-sentence report that he could cause a high level of harm if he offended again.

Allan repeatedly mouthed, "I love you", to his partner who was in the back of the court during his sentencing on charges of abducting a girl for the purposes of sexual connection, and having sexual connection with a young person.

The partner was in tears as Allan was taken away to begin his sentence for offending against a 14-year-old girl who was seen as a vulnerable victim. 

Judge Doherty said Allan's attitude to the victim was seen to be particularly callous and he had no consideration of the impact of his actions on the girl.

That was at odds with a letter he had now written, which the judge described as a "self-serving document".

Defence counsel Pip Hall said Allan could barely read and write and had help to write the letter.

He said Allan had pleaded guilty on the day of his trial when a rape charge was reduced.

The issue at trial would have been consent.

The abduction had involved taking the girl from one room to an adjoining room.

The abduction was witnessed, but the witnesses did not react by waking other adults who were in the house.

Crown prosecutor Deirdre Elsmore said the pre-sentence report was concerning because Allan took no responsibility for his offending.

"The intercourse here does seem very close to rape," she said.

Judge Doherty said Allan had threatened the girl so that she would not scream during the incident, and put his hand over her mouth.

The intercourse had caused internal and external injuries and she had been left with significant emotional trauma.

She reported that she had tried to end her life twice since the incident.

The judge said: "This intercourse does seem to be at the very extreme end of the consent spectrum."

He jailed Allan for three years, two months and said questions of rehabilitation would be dealt with by the Parole Board.

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