Chief Ombudsman Peter Boshier has announced investigations into the Ministry of Health's oversight of facilities and services for intellectually disabled people with high and complex needs.

He says the ministry's ability to resource, coordinate and plan services will be investigated.

"I will consider the capacity of the health system to meet the needs of some of society’s most vulnerable people," Mr Boshier says.

"I am aware at times there is a shortage of beds. This has meant some people have faced lengthy delays before being assessed as ordered by the courts. I will also consider whether some have been unlawfully detained in prison or other unsuitable places because there has been nowhere else for them to go."

The ministry contracts five District Health Boards to provide forensic intellectual disability services. The DHBs provide around 66 secure hospital beds nationwide.

"My investigation will look at whether the facilities are adequate for those referred by the courts for assessment as well as for long-term clients, women and youth. I will also look at how much workforce planning is being done to make sure there are enough appropriately trained staff."

Mr Boshier says he is conducting a separate investigation into the quality of the data collected by the ministry relating to the deaths of intellectually disabled people in forensic and residential care.