An inquest into the death of prison guard Jason Palmer has begun in Auckland.
The 33-year-old died after being punched by an inmate at Springhill Prison, Waikato, last year.
Latu Kepu pleaded guilty to the manslaughter of a prison guard. He had been caught stealing biscuits and chips from a fellow prisoner and was awaiting transfer to a maximum security prison when he threw the fatal punch.
The guard fell to the ground and hit his head on the concrete floor. He was unlocking Kepu's cell to let him out for his hour of recreation when the assault occurred.
Married with two children, US-born Mr Palmer was buried in Pukekohe in May last year.
Kepu pleaded guilty to manslaughter and was sentenced to six years and four months in prison.
The Corrections Association of New Zealand (CANZ) wants four issues to be considered and improvements made.
They include whether the prisoner should have been transferred to a maximum security prison earlier, whether the procedure to unlock prisoners was adequate and whether the process for assessing threats to prison officers was good enough.
While giving evidence at the coroner's inquest, Arul Prakash, principal corrections officer at Spring Hill, said Kepu had just been reclassified as a maximum security prisoner when he punched Palmer.
This followed an incident where Kepu was suspected of stealing biscuits and chips from the cell of a fellow prisoner, he said.
This was the last in a series of incidents that led to Kepu's reclassification.
Because Spring Hill does not deal with maximum security prisoners, Kepu was waiting to be transferred to Paremoremo, a maximum security prison.
As a precaution, Mr Prakash instructed that three staff members, instead of the usual two, unlock Kepu's cell.
Mr Prakash said if there were any safety concerns, he would have been the first to pick them up.
When Mr Prakash was asked by the coroner if anything could have been done differently, he responded, "I don't know, I don't think so".
The inquest continues.
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