A health assistant who indecently assaulted a patient in a psychiatric unit then accessed his confidential records and called him repeatedly once he had left hospital.
Deputy Health and Disability Commissioner Dr Vanessa Caldwell said the staff member (Mr B) sexually exploited the patient, "Mr A", who was in his 20s at the time.
"Mr A was a vulnerable consumer, and he should have been in a place of safety. Mr B's actions towards Mr A were a gross breach of trust and took advantage of Mr A's situation."
Four days after his discharge from hospital, the patient told his key case worker about the assault and the ongoing phone calls from his abuser asking him to meet.
The key worker helped him make a complaint to the police.
Mr A was able to give the police a recording of one of the phone calls from Mr B.
The health assistant - who was fired by the hospital for accessing patient records - later pleaded guilty to indecent assault and was sentence to 18 months' intensive supervision.
Caldwell has also found the unnamed public hospital service failed to offer the patient sufficient support after he reported the assault.
Te Whatu Ora Health New Zealand told the commission it started a full investigation of the incident after being notified by both the key worker and police.
At that time, it concluded the allegation of indecent assault "could not be substantiated" but it was able to establish Mr B had accessed patient details and contacted him out of work.
As a result, his employment was terminated with immediate effect.
However, Dr Caldwell said irrespective of the ongoing investigation into the indecent assault, it was "unhelpful" for Te Whatu Ora to assume Mr A would be able to use his usual supports for his existing mental health issues to deal with the additional trauma.
For example, it would have been reasonable to offer to pay for external counselling, she said.
"Instead, it appears that there was a 'business as usual' approach to Mr A's care, which failed to acknowledge that he had been subject to an indecent assault while he was an in-patient of the very service that was supposed to be supporting him."
There was a further opportunity for Te Whatu Ora to apologise when Mr B was convicted and sentenced, but it made no move to do this, she said.