Twice as many children from Catholic than Protestant backgrounds have been held at the only youth prison here.
Responding to a question from Sinn Fein MLA Pat Sheehan, Justice Minister Naomi Long confirmed that over the past five years 63% of kids at Woodlands Juvenile Justice Centre in Bangor, Co Down, are from a Catholic background.
She said: "The Youth Justice Agency is working with children, families and communities to address vulnerability and risk-taking behaviour through targeted support and early intervention, to prevent children being drawn into the criminal justice system.
"This approach has led to a considerable reduction in the number of children entering custody in Woodlands Juvenile Justice Centre - over the past five years, the average daily population has fallen from 34 to only 18 children.
"There is, however, a recognition that there is a disparity in the religious breakdown of those entering Woodlands with, on average, 63% of the children coming from a Roman Catholic background over the past five years."
The Justice Minister said that over-population of Catholic children at Woodlands is not directly within the control of the Youth Justice Agency.
Mrs Long added: "Woodlands is the recipient of children sent by police and courts, they must accept and work with every child referred, and have no right to exclude, nor options to assess suitability, before accepting a child from court. As corporate parents, Woodlands staff deliver all necessary supports and services to children in their care, including providing for their spiritual and religious needs."
Woodlands, based at Rathgael Road on the outskirts of Bangor, comprises six units each with eight en suite bathrooms. It has a capacity for 48 boys and girls between the ages of 10 and 17, who are given private bedrooms and are allocated a dedicated key worker. A normal day is spent taking part in educational classes and life-skills programmes.