Health staff could not have prevented the escape of a man who was undergoing a mental health assessment at Canberra Hospital's adult mental health unit, an initial review of the incident found.
Canberra Health Services executive director of mental health Katie McKenzie said staff had followed all necessary procedures and processes after a man escaped through a window.
Jessie Gould, 32, was at the unit after being referred by a magistrate's orders. He was still missing as of Tuesday evening.
The security of the territory's mental health units has again come under scrutiny from the ACT's opposition with shadow opposition mental health spokesman Ed Cocks saying units need to be better at managing risks.
"It's really important that we draw a distinction between patients who have turned up to have their mental health treatment and to be looked after in the system and when we have people being transferred from the justice system into one of these facilities," he said.
"People are asking why was this patient being evaluated in an unsecure facility when they had come from the justice system."
The adult mental health unit is a closed facility but Ms McKenzie said there was still a range of security measures in place.
"We also have other security means as well as the doors. We have secure windows and we also work in very close collaboration with our security guards who are part of the team so we do have security guards when needed," she said.
Ms McKenzie said there were patients who had been admitted voluntarily and involuntarily to the adult mental health unit and emphasised the overwhelming majority of people with mental illness were not a risk.
"It's really important we remember that people with mental illness on the whole do not pose a risk to community safety and that's probably a key point that I would like to reinforce is that people with mental illness should not be seen as unsafe," she said.
Mr Cocks referenced an ACT chief psychiatrist's report into the circumstances surrounding an alleged stabbing at the Australian National University by a patient on approved leave from a secure facility like Dhulwa or Gawanggal.
The report, released last week, recommended a major shake-up of leave provisions, including legislation changes and consideration of community safety when making decisions about whether a patient can be on approved leave.
"There are really concerning echoes of the report the chief psychiatrist released just a week ago in this event," he said.
"One of the key findings of the chief psychiatrist's report was that the system needs to be better at identifying risk and managing both the risk to the individual and to community safety.
"That's been a key consideration that hasn't factored in this time."
Mr Cocks took aim at Minister for Mental Health Emma Davidson, saying there had been a series of failures in the system under her watch.
Ms Davidson fired back, saying the provision of services was complex and the opposition should not politicise someone's health needs.
"Unlike Mr Cocks I wait for the facts and make informed decisions about what needs to change to prevent issues from occurring again," she said.
"Mr Cocks did not ask my office for information about this incident, nor has he discussed with my office ways to improve Canberra's mental health system.
"I genuinely can't recall an occasion where he has put anything proactive forward."
- Support is available for those who may be distressed. Phone Lifeline 13 11 14; Men's Referral Service 1300 776 491; Kids Helpline 1800 551 800; beyondblue 1300 224 636; 1800-RESPECT 1800 737 732.
