Registered nurse Arthur Moutakis failed to manage complaints and adequately perform his role as a member of the clinical governance committee at the Older Persons Mental Health facility in Oakden, the South Australian Civil and Administrative Tribunal found.
The facility closed in 2017 after a report by the state's chief psychiatrist revealed abuse and neglect dating back 10 years.
The SA corruption watchdog released a report in 2018 which found the facility's residents suffered neglect due to a shortage of staff that rendered the facility "medically unsafe, as well as reports of patients being assaulted".
The then-Independent Commissioner Against Corruption Bruce Lander described Oakden as a disgrace and declared the affair a "shameful chapter in the state's history".
Subsequent investigations by the Australian Health Practitioner Regulation Agency led to the referral of staff to tribunals, including former manager Julie Harrison who was disqualified from nursing for a decade last December.
In January, former Oakden nursing manager Kerim Frederick Skelton was banned from applying for registration for 12 years.
On Monday, the tribunal announced it had found that Mr Moutakis engaged in professional misconduct, supporting findings by the Nursing and Midwifery Board of Australia that he failed to adequately manage three specific complaints and failed to adequately perform his clinical governance responsibilities as a member of the governance committee.
The tribunal ordered that he be reprimanded and his nursing registration cancelled. He was also disqualified from applying for registration for three years and banned from providing any health service.
Board chair Veronica Casey welcomed the latest tribunal finding and hoped it may bring some closure.
"These vulnerable residents put their trust in nurses, managers and facilities to care for them when they need it most and it's important that this trust is upheld," Adjunct Professor Casey said.
"These investigations uncovered practices that fall a long way short of community expectations and the need for health practitioners to discharge their professional responsibilities, including in relation to clinical governance, even in failing health services."
Mr Moutakis held the roles of consumer adviser and consumer liaison officer at the facility, which catered to older people with severe mental illness, including those suffering from dementia, between 2007 and 2017.
The tribunal rejected a submission that his behaviour was an isolated incident, given the misconduct occurred over a sustained period of time.
The regulation agency's CEO, Martin Fletcher, said the tribunal outcomes underline the importance of the work of his group and the nursing and midwifery board for public protection.
"The residents at Oakden did not receive the level of care that they were entitled to expect," Mr Fletcher said.
"It is imperative that we learn from these events to improve patient safety and ensure that this can never happen again."
