ACT executive director for children, youth and families Mark Collis said the 38 children involved in an analysis of child protection were some of the most complex cases dealt with by the system.

The report, released under Freedom of Information, showed more than 80 per cent of children involved in the review were subject to family violence for years with minimal change or intervention, and about 70 per cent of the same cohort were found to have suffered serious neglect that persisted over several years.

Dr Collis said the report on the first year of operation of the case analysis team was prepared for quality assurance.

It was designed as a mechanism of oversight, to help front-line case workers manage difficult and complex cases.

"Of the 38 kids, that represents probably amongst the most complex of the work that we do," Dr Collis said.

"You really can't generalise the demographics around that group to the broader population of the work that we do."

Dr Collis said it was standard across Australia that the three main drivers for child protection were family violence, drug and alcohol use, and mental illness.

"Those three things account for over 90 per cent of the variables that lead people to child protection," he said.

"So whilst the presentation of this group with severe drug and alcohol and severe violence arrangements isn't representative of the broader view, the reality is if you look at the 3000 to 3500 people we're working with, nearly all of those will have one or most likely two of the factors in play in their family, and that's what has driven them to our door."

He said it was hard work to balance the harm to children of being removed from their parent and the harm of being exposed to violence.

"The generational impact of [domestic violence] on children is quite significant but we have to balance that with the fact that it is incredibly traumatic to take a child away from a primary attachment figure."

ACT Family Safety co-ordinator-general Jo Wood

said the report was useful to get a sense of what child protection workers were grappling with.

"We know family violence is a very common issue in child protection cases, so the fact the number is high isn't surprising," she said.

Ms Wood said it was important for the territory to focus on dealing with the perpetrators of domestic and family violence, and there was plenty happening in the space to intervene earlier, including the implementation of the Family Safety Hub.

Dr Collis said the government was also coming to terms with the message from some members of the community that people in these relationships didn't want them to end, they just want the violence to stop.

He said he was looking forward to the implementation of a new computer system later this year, as the current system was 20 years old and not accessible to case workers in the field.

He said the new system would give case workers a way to track markers of cumulative harm, something the report deemed "an evident or emerging concern" in the majority of cases.

"It's probably one of the most difficult areas of practise in child protection because no single event might reach a threshold that we would think is problematic for a child, but if you take the child's whole life story and put that in context you might see an accumulation of that."

He said identifying markers for cumulative harm was a new focus for the territory's case workers.

Liberals spokeswoman on families, youth and community services Elizabeth Kikkert said the report showed that Canberra children had been left in situations exposed to family violence with minimal change or intervention.

"Based on this fact, I can say that I lack confidence in this government to make these corrections," Mrs Kikkert said.

"Children should never be left in circumstances that expose them to known violence over the course of years. If the ACT government is serious about children's rights and wellbeing, they should fix this problem as a matter of priority."