The treatment of a man who has been in preventive detention for 45 years has been described as a disgrace by a lawyer who is taking the case to the United Nations (UN).
The 58-year-old man was first detained on sex offences when he was 13.
His lawyer, Tony Ellis, said he could not be named because of an extreme intellectual disability but that he had been in psychiatric institutions or prisons since 1969, bar one year of freedom in the 1990s.
A report prepared by Mr Ellis said the prisoner had an IQ of 55, and there were not enough places available to treat him.
The man's low IQ meant he could not be held responsible for his actions and should be under medical management rather than in prison.
Mr Ellis said he expected a response from the UN within six months.