Police officers were needlessly put in danger during the riots at Parliament when they were sent in without the correct protective gear, police advocacy groups say.
About 150 officers were injured on 2 March last year during the full day push to remove protesters from the grounds and end the anti-mandate occupation.
Speaking to RNZ, Police Association president Chris Cahill said many officers were not provided with the necessary speciality shields and helmets.
"Rocks were being thrown at them. Some had small shields, some had none at all, and very few had helmets to protect them," he said.
"There really wasn't enough kit in the country."
Cahill said it was a matter of luck that the injuries were not more serious.
"Some of those bricks that were thrown, the paving stones that were ripped out, if they'd hit an officer in the wrong place with the right level of force, someone could have died."
The Independent Police Conduct Authority (IPCA) is reviewing the policing of the protest - including equipment provided - and is due to report back by the end of March.
Police were asked for a response but a spokesperson said they were unable to provide comment while the IPCA review was ongoing.
Allister Rose is a former police officer turned health and safety advocate at Blue Hope Foundation, a health and safety charity for police officers.
He told RNZ he believed as many as 200 officers were sent into the riots without the appropriate protection.
"A number of our members have come forward and spoken to us and haven't been happy about the amount of equipment that they were supplied with.
"They've been mentioning that they haven't had enough shields, head protection and head protection with visors."
Rose said he believed the police headquarters knew they did not have enough protective equipment but pushed ahead regardless.
"They went ahead with the plan anyway - and police officers' health and safety was put at risk," Rose said.
He said it was his view many of the injuries inflicted on 2 March could have been avoided.
"If it was any other business in New Zealand, WorkSafe would be taking a special interest."
Cahill said he understood the police were already trying to boost the supply of protective equipment but believed more training was also necessary to be better prepared next time.
"The police certainly have to take every step they can to mitigate any risk in deploying police staff and we could argue that that wasn't necessarily the case for all staff on that day."