Police failed in their duty of care after a detainee tried to take their own life in a Tauranga court cell and later died in hospital, according to an Independent Police Conduct Authority decision.
The authority released its findings today after the man's death in 2017.
The man, known as Mr X, was taken into custody on October 7 2017 and taken to Tauranga District Court for a hearing on October 11.
At 12.35pm, the man was found unconscious in a cell.
He had not been checked for more than 20 minutes before he was found.
Police policy requires items that a detainee could use to harm themselves to be removed.
The Authority also found that the initial evaluation of Mr X was inadequate in a number of respects and handovers from outgoing custody staff to incoming staff were inconsistent.
In addition, he was not checked as regularly as he should have been for the four days he was in police custody.
In a statement today, Bay of Plenty District Commander Andy McGregor said police took their responsibility in regard to the management and care of people in their custody seriously, and an outcome where someone was injured in their custody and later died was tragic.
"The issues raised in the report in regard to the failure to follow processes have been raised with the staff involved and the need to adhere to the policies in place has been reinforced.
"We have met with the man's family and we continue to support them.
He said they were committed to offering the highest level of service to people in their custody.
"Work on a national review looking at the safety of prisoners in police custody is ongoing and the IPCA findings will feed into this work," he said.