Over half of secure beds for seriously at risk children are closed because of staff shortages, according to the latest report from the Child Care Law Reporting Project (CCLRP).
The report, which gives details of in-camera child and family court cases, notes that there are only 26 secure beds in the State, and that just 14 of them are available.
In one case, a High Court judge said that while they understand the recruitment difficulties, the child and family agency Tusla is well funded and "should be in a position to sort out this glitch in order to make use of what are hugely impressive facilities".
CCLRP Director Carol Coulter said these are children who are "very seriously troubled".
Tusla has said that 15 beds are open today - eleven in Dublin and four in Limerick.
In a statement, the agency said that "11 more are within the available bed complement built but repeated efforts to attract and retain staff in this aspect of work have proved enormously challenging."
Tusla said it is taking steps to address this challenge.
Speaking on RTÉ's Morning Ireland, Ms Coulter said they often have psychiatric and behavioural problems and could be homeless.
"They often come from very troubled backgrounds and are a great risk to themselves and sometimes to other people, because their behavioural problems can include very violent behaviour.
"You could be looking at children who would be a real threat to the public and certainly a threat to themselves," she said.
Ms Coulter said these children need intensive therapy and a secure environment, which is why they are placed in special units.
She said some children have such acute problems that the specialist treatment they need does not exist in this country and they are sent abroad, usually to the UK.
"A small number of children are involved, it's a very expensive process. It does reflect a rather ad hoc approach over the years to dealing with these problems rather than a long term plan".
Ms Coulter said a number of children who are sent abroad are those with eating disorders, because it is not recognised in Ireland as a mental health issue.
She said the report also notes a disproportionate number of children from minority or ethnic backgrounds coming before the courts, and that more research is needed as to why this happens.
"Social isolation and cultural differences are sure to be playing a role. As we know, homelessness does disproportionately affect people from minority backgrounds. The problems that lead to children going into care in the Irish community - alcoholism, mental health problems - they affect people from ethnic minorities as well".
Ms Coulter had previously said that the system in relation to child and family cases is "overburdened" and that a dedicated family court is needed to deal with these cases.
She said legislation in the Department of Justice is "very well advanced" and she is optimistic that we will see legislation to set up a family court "very very soon".
She called on "whatever government that comes in" next to "make this a priority".