The man defecated on his cell bed and attempted to eat a food container and plastic utensils, his cell remained unclean for several hours.
The man assaulted an officer the next morning and that afternoon officers had to use a shield to restrain him on the ground while he was being transported to prison.
While restrained on the ground, the man lost consciousness and was subsequently taken to hospital.
It has not been determined what caused the man to lose consciousness, the report said.
"Having interviewed witnesses and reviewed the footage of the man being restrained on the ground, the officers' use of force was reasonable under the circumstances. There is no obvious indication any officer restrained Mr X in a way which would cause him to struggle to breathe," said authority chair Judge Colin Doherty.
The authority found the use of the shield was reasonable but the restraint procedure was poorly executed.
While officers provided timely and appropriate medical care, they should have made more of an effort to uphold the man's dignity when his gown was cut off him, the report said.
"The police and corrections officers working within the custody suite were unsure exactly who was in charge of extracting the man from his cell.
"The authority has recommended police, corrections and the Ministry of Justice collaborate to clarify at which point each agency is responsible for remand prisoners in the custody suite."
The police have accepted the findings in the IPCA report.
"Police also acknowledges that there were several areas to improve in the
decisions made by officers while managing the man referred to in the report
as Mr X."
The man was known to be challenging to manage and presented a violent risk as
well as a health risk, a spokesman said.
