When Cameron John George (26) was approached by police about the incident in March last year he indicated his surprise at his good fortune in how things had unfolded, the Dunedin District Court heard this week.
The officers then informed him of the victim’s age.
George pleaded guilty to unlawful sexual connection with an underage girl.
Counsel Steve Turner said his client had reasons to believe the victim was over 16 but accepted he did not take reasonable steps to confirm that.
"He was shocked to learn her true age," Mr Turner said.
"It was 15 minutes of madness, so to speak."
George came across the teenager at 3am after she had crashed her car at Arrow Junction; he stopped, and she told him she was trying to get to Alexandra.
George told her he was about to begin his delivery run but could drop her there in five hours.
She agreed to accompany him, and the pair discovered they had mutual friends, the court heard.
Mr Turner said some of the people mentioned were at least 20, which further suggested to George the girl was older.
The conversation moved from previous relationships to sex.
George asked the teen if he could perform a sex act on her.
She agreed and they stopped outside Cromwell, where the 15-minute interlude took place.
George dropped the girl in Alexandra as arranged.
"It was opportunistic offending," Judge Jim Large said.
He accepted it was a case of George not making the necessary inquiries rather than predation.
Mr Turner said George was now working as a chef in the North Island where he had family and employer support.
He had saved $1000 to offer the victim before sentencing.
"[That] indicates to me you’re not someone who says you’re sorry ... you’ve actually saved some money and shown your remorse," the judge said.
He sentenced George to six months’ home detention and refused to place him on the Child Sex Offender Register.
