Jacinda Ardern says the Government had to rely on instinct, not evidence when deciding what measures to implement in response to the coronavirus pandemic.
On March 24 the Prime Minister announced New Zealand would be going immediately into alert level 3, followed by level 4 in 48 hours time.
Ardern has received worldwide praise for the 'go hard, go early' approach, but she told The Spinoff the decision was made amongst rapidly changing information with little direction.
"There was a huge degree to which we were stepping into the unknown and also the pace of decision making," she says.
"Sometimes you just had to anticipate, you knew what the science was, you knew what the evidence was telling you, but you didn't know how it was going to roll out here in our context," she told The Spinoff.
Ardern says it was the early decisions were about finding the right balance between health and safety, and the economic cost to New Zealand. If they didn't make the right decision the "ramifications were huge".
She says it was instinct that helped the Government decide to implement the lockdown.
"At no point did the science and evidence say in absolute terms that this is exactly what needs to happen and this is the exact point at which it needs to happen," she told The Spinoff.
"There was a lot of judgement applied there."
Now Ardern wants to use the pandemic to address New Zealand's major social issues.
"I want to look back on this period and say that there are things that could have gotten worse because of COVID that we managed to actually make better: Our housing crisis, child poverty and equality, and environmental issues."
New Zealand has had no new cases of COVID-19 since May 17 and only 30 cases remain active.