The motion, led by Canberra Liberals' corrections spokeswoman Giulia Jones, called on Mr Barr to advise the Legislative Assembly if Mr Rattenbury "is an appropriate fit for role" and if he had full confidence in the Greens minister.

While the motion was almost certain to be voted down, as it eventually was, in the Assembly, it comes as the Opposition has been increasing pressure on the government's performance in corrections after a spate a series of serious incidents at the Alexander Maconochie Centre.

Among those incidents, Mrs Jones said escapes from the prison and Canberra Hospital, the accidental release of a prisoner, and two recent deaths in custody, had brought Mr Rattenbury's performance under question.

"Another year, another discussion about the failings of the AMC, not another overdose, fortunately," she said.

"Prisoners who are meant to be locked up shouldn't be allowed to walk out the front door, I would have thought this was prison management 101, it's astounding," she said.

Mrs Jones said she late last year wrote to Mr Barr outlining the series of events in the prison, also criticising Mr Rattenbury's performance, given he had been in charge of the prison for five years.

But she said he responded saying he did not agree with her characterisation of events, or her characterisation of Mr Rattenbury's performance, in questioning his suitability in the role.

"Or does the Chief Minister think that's fine, that everythings going okay in our prison?" she said.

Mrs Jones questioned whether Mr Barr disagreed "with the fact that inmates have died in custody", others had escaped and two indigenous brothers had been seriously assaulted in the AMC in recent months.

But Mr Rattenbury said despite what she may believe he and his staff in corrective services were striving every day for a prison where detainees were safe, secure, to improve and be rehabilitated.

He said the recent report on government services showed the territory government had continued to be the top-ranking jurisdiction for education and training for detainees.

"ACT corrective services is currently undergoing a significant period of whole of organisation reform and since April 2017 there have been holistic changes including changes in leadership and structure, governance arrangements and operational practice," he said.

"We can never entirely account for human behaviour, we can do things better and we can mitigate risk more proactively abut ultimately incidents will occur.

"The measure of our maturity and the measure of my capability as minister for corrections can be found in how we respond to the types of incidents Mrs Jones raises in her motion."

In a brief comment during debate, Mr Barr said simply that he supported Mr Rattenbury's comments in the Assembly, and he rose to "reaffirm that Minister Rattenbury, as minister for corrections, has my confidence".

The motion was ultimately voted down by Labor and the Greens in the Assembly.