His M4 Bushmaster rifle unexpectedly discharged as he leaned forward to help lift the man from the ground when the AOS operation had come to an end.
The police officer's lawyer, Jonathan Krebs, said his client had not received the training he needed to adequately equip him for the front line.
"In a way he was unintentionally set up," Mr Krebs said. "The armed offenders squad was short staffed, it seems corners were cut."
Mr Lynch confirmed that the association would be conducting an investigation into areas around health and safety as well as resourcing. He said there appeared to be issues around police not relaying information about rifles on to other members and work would be carried out in this area.
A police spokeswoman said that after the investigation into this incident, the police had made enhancements to armed offenders squad instructions, training and equipment.
"Police notes the court's decision" and "the community can be reassured that the Eastern Police District, including the Hawke's Bay area, has the appropriate response capability to respond to an incident involving an armed offender", the spokeswoman said.
The police force at present has 16 armed offenders squads, comprising about 300 staff, spread around New Zealand, who can also be called upon to assist one another in the event of any significant armed incident.
Appropriately qualified frontline staff also have access to firearms and can respond when necessary.