Published Thursday, 29 March 2012
Most prisoners in Maghaberry are on medication. (© UTV)
It revealed that 16% of those placed in custody meet the assessment criteria for mental disorder.
In Maghaberry, 700 out of 850 prisoners are on medication, mainly tranquillisers, while 7% of the whole prison population are thought to be seriously mentally ill.
While some improvements have been made, the CJI said many challenges remain.
A joint working group has been set up by the health and justice departments but it has to date had a "limited impact" on the ground.
It shines a light on the scale of that challenge and concludes that more needs to be done to address the issue.
Justice Minister David Ford
Dr Michael Maguire from the body said the scale of the task the criminal justice system in NI faces should not be underestimated.
"Progress in the last two years has been slow despite the recognition of the great challenges facing the criminal justice agencies in caring for prisoners with mental health issues," he said.
"The early assessment and screening of people with mental health problems remains difficult as they enter into the justice system.
"There are still no clear rules about where people are to be taken when they are arrested or detained by the police."
The report entitled 'Not a Marginal Issue: Mental health and the criminal justice system in Northern Ireland' is a follow-up to an inspection made in March 2010.
Dr Maguire added: "The 2010 report highlighted a range of deficiencies for those in the system with mental health problems and was published in order that their treatment would improve.
"There have been some improvements in the information shared between organisations as well as the information given to the court about people with mental health issues.
"It is not possible to say however, whether this had made any difference to the extent to which people have been diverted away from custodial care."
Other stark figures outlined in the report revealed that 78% of male prisoners on remand and 50% of female prisoners are personality disordered - seven times that of the general population.
A quarter of those committed to jail every year say they have been in touch with mental health services in the community.
Amongst sentenced prisoners, 64% of male and 50% of females have a personality disorder.
"These statistics reveal the scale of the problem. Progress has been slow and it's important that we continue our efforts to meet these challenges," Dr Maguire added.
"Protecting the public from criminals is just one facet of the criminal justice system; providing prisoners with education and health care as part of their rehabilitation is another so that the likelihood of reoffending on release is reduced. That makes for a better society for us all."
Justice Minister David Ford has welcomed the report.
"This report reinforces the fact that many people who enter the justice system suffer from some form of mental illness," said the Alliance minister.
"In our prisons, improvements have been made in assessing those who are placed into our care by the courts and the transfer of healthcare responsibility to the South Eastern Trust should improve those arrangements.
"Over the last two years and since being elected Justice Minister, I have made the case time and time again that the solution to many of the problems in the justice system does not rest solely with my Department.
"I am determined to work in partnership with others to make a real difference, and I welcome the thrust of the CJINI report which finds that improvements are not only required between the different justice organisations but across Government."