A 65-year-old Victim Support area manager condemned a young boy to a "life sentence of guilt, confusion, anger and turmoil" when he should have been the person his family could have counted on.

David John Charteris was jailed for 14 years on Friday after being found guilty at a judge-alone trial of seven charges of sexual violation by unlawful sexual connection and one charge of indecency with the boy, who was aged 10 to 12.

Charteris' Linked-in page online now describes him as retired.

The victim, a father now in his 30s, told the court Charteris had "exploited" him and said his employer was "the very organisation that should have been available to support me".

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Charteris was victim support Victim Support service co-ordinator for Christchurch and North Canterbury for two years and area manager for Victim Support in Otago and Southland. He was earlier a photo-journalist for The Press. 

Charteris denied the offending at trial and continued to deny it at his pre-sentence interview with probation. He also sat shaking his head in the dock as the judge described the offending he was convicted of at trial.

The Christchurch District Court judge for the trial and the sentencing, Judge Raoul Neave, said if Charteris maintained his attitude of denial, he could not expect early release from prison which meant he would serve the whole term.

Charteris was aged in his 40s when the offending occurred, the Crown said at the trial in May.

The victim's statement was read in court, saying Charteris' offending had condemned him to "a life sentence of guilt, confusion, anger, and turmoil". He said Charteris has exploited him with "grooming and the illusion of support".

His life had been "stalled" during the long court process, affecting his employment and his time available with his children.

He said Charteris' offending for his "selfish needs" had effects on his mental health, caused distress, and caused havoc in his personal and professional relationships.

Crown prosecutor Kerry White said Charteris had exploited the boy when his family were going through emotional turmoil with a marital break-up.

She spoke of Charteris planning the offending through taking the child out for drives during the day.

Defence counsel Anselm Williams said Charteris maintained his innocence, but acknowledged he had to be sentenced in terms of the verdict. He said there were health issues that would make the prison term more difficult. He had been heavily involved in the community, and suffered from depression and anxiety.

Judge Neave said the victim had not been groomed or targeted, but Charteris had taken advantage of circumstances and had organised situations where the offending could occur. This involved arranging outings, or having the boy at his house when his flatmate was out.

The boy's mother had nothing to reproach herself for. She had turned to Charteris to be a friend and mentor for her son at a difficult time. A range of sexual acts then occurred over more than a year.

There was significant harm to the victim, the scale of the offending was significant, and it was a breach of trust.

The judge decided to reduce the jail term because of Charteris' otherwise good character which involved contributing thoroughly to the community. He also reduced it for the health difficulties he faced ahead of the prison term.

Charteris and the Victim Support organisation have had interim suppression orders until Friday, when the judge said the orders lapsed. Some suppressions remain.