Destiny Church leader Brian Tamaki is set to face charges for organising the anti-lockdown protest over the weekend.
In a statement to Newshub on Monday, a police spokesperson said they were considering charges in relation to the organisers of the event. Tamaki is one of them.
Police said they were in the final stages of their investigation into the protest of around 1000 people, which breached alert level 3 restrictions.
The only gatherings allowed under alert level 3 are weddings and civil union ceremonies, funerals and tangihanga, with up to 10 people. People must remain in their household bubbles when not at work or school and masks remain mandatory outside of the home.
Police said they were "disappointed at the large numbers, and that organisers did not follow through on undertakings they had given police about how the event would be managed".
Tamaki could face six months in prison or a fine of up to $4000 for breaching a Health Order. More charges could follow but the current investigation is focussed on the protest's organisers.
More than 1000 people protested against COVID-19 restrictions on Saturday outside the Auckland War Memorial Museum, and despite breaching alert level 3 gathering rules, no one was arrested.
Auckland City District Commander Karyn Malthus said on Saturday the police presence of about 20 officers at the protest was "one of observation and monitoring", rather than arresting people.
"To arrest people today was not the safest course to take with a crowd that size."
A petition calling for protest leader Brian Tamaki to be arrested has reached nearly 65,000 signatures.
"To date the New Zealand Police response over Tamaki's actions has been abysmal," the petition on change.org reads. "All involved were in breach of the current regulations covering groups and gatherings."
Tamaki said on Facebook Kiwis should be grateful.
"What price do you put on your personal Freedoms? Why would you hate us for that? As for the pathetic cry, you will cause a super-spread, is unreasonable panic," he wrote.
"You're vaccinated, not in the vicinity, and safe in your bubble, you then should be thanking us, who took the courageous risk, in the face of restrictions, to push back on oppressive laws from this Government."
Prime Minister Jacinda Ardern said on Sunday the protest was a "slap in the face" for Aucklanders following the rules.
"Look, ultimately, the police response to the protest activity in Auckland on Saturday is a matter for them. It is operational - very important that I don't step into their decision making on the ground - but I have faith in the judgment of the police to manage all sorts of situations within COVID when it comes to compliance.
"I do, however, have a personal view on the protest itself. It was wrong. Obviously, it was illegal, but also it was morally wrong. What does it say to every Aucklander who has given up a huge amount over the past few weeks to do the right thing and keep other Aucklanders safe? It was a slap in the face to them."
A police update on Monday showed that since alert level 3 was implemented, 11 people had been charged with a total of 11 offences for breaching COVID-19 lockdown rules.