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A man convicted of sexually assaulting an elderly woman during a rest home visit was regularly visiting rest homes and retirement villages.
Last week former Massey University journalism lecturer Grant Hannis, 55, was sentenced to eight months home detention for kissing and intimately touching an 82-year-old woman who was trying to get away.
The incident happened while he was visiting another person at the home, but RNZ has found he was regularly visiting rest homes and retirement villages as part of a jazz band.
The band also played for bowling clubs and the Good Companions Club for over 55-year-olds.
One rest home said when the band visited they had been escorted into the hall and escorted out, and there was no point where residents were in private spaces with Hannis.
Another said it had checked its records, and there were no complaints registered after the bands visit.
Several said they do police checks of permanent staff, and keep a careful watch over who is on their premises, but also need to allow visitors to come and go.
The retirement facilities visited by City Jazz include Rita Angus, Sevenoaks, Alexandra Rest Home, Kāpiti Retirement Village, Huntleigh Retirement Village, Malvina Major, Waikanae Country Lodge, Sumerset at Aotea, Kāpiti Midland Gardens and Charles Fleming Retirement Village.
Age Concern educator Hanny Naus said the elderly found it particularly difficult to report abuse.
"People have lots of reasons for not disclosing. Particularly for older people there's more of the issues around vulnerability.
"Are they able to speak up themselves if someone is abusing them? Are they dependent on that person?"
She said 15 cases of sexual abuse against the elderly were reported to their organisation last year.
Sexual abuse in any age group is estimated to be significantly under-reported, and she said it is likely cases involving the elderly are the tip of the ice-berg.
Elderly people feel stigma against raising topics that were socially taboo for their generation, and as with any sexual abuse victims, may feel shame, confusion or self-blame, and worry they won't be listened to. Mental impairment, trouble with memory or communication could also factor.
Ms Naus said Age Concern works with families who are concerned something is going on, to advise them how to talk it over, and what they can do.
Hannis appeared in the Wellington District Court last Friday on a charge of indecent assault.
Judge Stephen Harrop outlined his offending, saying he followed his victim into her room at the resthome and shut the door.
"You kissed and touched her and put one hand on her breast and with the other rubbed her vagina on the outside of her clothing as she tried to push you away.
"You closed the curtains and again kissed the victim and touched her vagina. A caregiver saw you and ... left to find a manager."
In a statement last week, Massey University said Dr Hannis told no-one that he was being prosecuted, and by the time staff became aware, he was no longer teaching.
"This has come as a great shock to colleagues and no doubt to many students, past and present," Massey University said.
It said Dr Hannis had worked at Massey since 2003 and requested early retirement in October, which took effect in December.
"Dr Hannis should have told his manager about the charge he was facing as soon as it was laid so that Massey could have considered his employment position."
Police declined to comment.