What the Prime Minister told her Cabinet before moving out of lockdown has been revealed.
On April 20, Jacinda Ardern presented a 23-page paper on the decision they needed to make about moving to alert level 3.
New Zealand was doing well and evidence was growing there wasn't widespread community transmission. But a shift too early could mean stints of going back into lockdown for the rest of the year or until a vaccine arrived.
But cautiously moving to level 3 was the only way to test what the effects would be, Ardern said in the paper which was included in hundreds in today's release of Pandemic Papers.
"Whenever we step down, as we move to our new reality, I expect the enormous scale of the challenges the virus has brought to our economy to come more directly into focus.
"Our actions have ultimately served our people's health and livelihoods, as unmitigated spread would have been an economic as well as a social and humanitarian disaster."
Ardern said whatever choice the ministers made, much would depend on the goodwill of New Zealanders.
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And Cabinet needed to be prepared to move back into lockdown if needed "despite the enormous imposition" if the measures hadn't worked, Ardern said.
"We now face a choice of when to step to alert level 3."
Ultimately Cabinet decided to slightly extend the lockdown until after Anzac weekend on the advice of director general of health Ashley Bloomfield.
The three choices
Ardern presented three scenarios to the decision-makers on April 17 about how the lockdown could be lifted - and warned they had to be prepared to go back if things didn't go to plan.
Ardern believed that from midnight on Wednesday April 22, New Zealand was in a position to support a higher level of social and economic activity and meet demands in the health system now while still continuing on the path of elimination.
Scenario 2 - Bloomfield's option
Extend lockdown for five more days and move to level 3 controls after Anzac Day weekend.
The extra five days at level 4 would increase confidence in the positive trends seen in the data, said Ardern.
More results from the extra testing would be available to give greater certainty that New Zealand was on track to avoid the negative scenarios that early modelling was suggesting would occur.
It would also moderate concerns about a sudden change and allow more businesses and their workers to prepare for the new conditions.
This option was recommended by Bloomfield.
Extend the Level 4 controls for a further two weeks, which meant further confidence in the trajectory of cases and the chances of unexpected outbreaks.
But it would come at "significant additional cost to our economy, our businesses and workers, and their families".
"Further, with such low numbers of cases now being reported, this option runs the risk of eroding the support of the community that we presently enjoy."
New Zealand was doing well
At the time Cabinet made the decision, lockdown compliance was high, which meant a sharp reduction in the number of new cases and increasing confidence there wasn't undetected community transmission.
New Zealand had curbed the infection rate (R0) to 0.48 - the number of people who caught the virus from an infected person - compared to 2.5 overseas.
And although New Zealand had a relatively low proportion of serious cases compared to other countries, the virus had spread to some especially vulnerable communities - rest homes, in particular.
The health system was not under significant pressure with hospitals operating at 50 to 60 per cent of their normal capacity, but other strains were emerging.
General practices were at risk of financial collapse, 7300 inpatient surgeries had been delayed and more than 70,000 appointments cancelled.
Ardern said there was sufficient personal protective equipment.
A week later on April 22, Cabinet was told the number of gloves and disposable aprons wasn't enough to meet expected demand and although masks, gowns and face shield supply was good, the supply of glasses was barely enough.
Business confidence in freefall
Although New Zealand was on track to achieve its health outcomes, Ardern said business confidence was "in freefall", which could affect investment needed for recovery.
Economic forecasters expected a 15 per cent shrink in GDP and a 9 per cent rise in unemployment by June 30. Visitor numbers were zero and the Government was seeing the first signs "of what is expected to be a significant decline in the housing market".
"The longer the lockdown continues, the fewer businesses will survive and the more people will lose their jobs."
And the lockdown was being felt disproportionately by smaller businesses - larger ones were more likely getting the economic benefit of being counted as essential - and by people on lower incomes or with low savings.
"The closure of retail businesses has a disproportionate impact on low paid employees, and the shuttering of construction has particularly negative effects for Māori and Pacific workers."
Ardern told ministers their decision could mitigate the income effects of the lockdown.
"Under any scenario, New Zealand will face a long period of economic recovery, and this will last years if not decades.
"We must do all we can to avoid the scourge of widespread unemployment, which will particularly harm vulnerable groups, especially in the regions, and older workers."
Impact on vulnerable groups
After moving into alert level 3, the next stage of health surveillance needed to uncover the health and infection in the more vulnerable communities in the country, Ardern said.
Within the Māori and Pacific Island populations particularly, households struggled with crowded living conditions that make the management of any infection difficult and often included older family members.
Any move out of lockdown would have to be coupled with measures to protect people over 70 years old or those with existing conditions.
"This will be accompanied by key messages for everyone to ensure that older people are respected and do not face verbal criticism from the public when they take opportunities to leave their homes and are taking precautions."
And even with restrictions slightly eased and 400,000 back at work under alert level 3, about one million New Zealanders, equating to 40 per cent of the workforce, would have to stay home.
Would level 3 work?
"It is uncertain how effective our level 3 measures will be in slowing the spread of the virus," Ardern said in the paper.
That's why she wanted to err on the side of caution.
"They [level 3 measures] were built from the best available public health advice. And they are more equitable, since our approach to business in particular is more open than the restriction to essential services of the emergency requirements under level 4 allows."
If level 3 wasn't successful, New Zealand would need to go back into lockdown several times for the rest of the year or until there was a vaccine or treatment.
Modelling from Auckland University professor Shaun Hendry showed two scenarios if New Zealand moved to alert level 3 on April 23 in Scenario 1.
One showed more effective controls with each infected person infecting fewer than one other (R0 = 0.94) and less effective controls showed an R0 of 1.22.
"These short-term results foreshadow the start of the familiar and unwelcome spike of exponential growth."
A regional approach
Cabinet asked officials to develop a plan for regional de-escalation,n which involved 16 regions and at least 84 road blocks. But it wasn't supported by a number of key ministries.
In deciding the move to level 3, Ardern said the impact of the virus was "quite different in different places".
As at April 17, eight DHBs had reported 20 or fewer cases and the six with the smallest populations had no or only a handful of cases in the previous 10 days.
By contrast, Auckland, Waitemata, Waikato and Southern DHBs, which serve 39 per cent of the population, reported 56 per cent of the cases.
A regional approach was possible, said Ardern, and a more differentiated response would also make decisions to raise levels less difficult "since the consequences of stricter controls would be lessened by a more narrow geographic reach".
But it wasn't recommended for a move out of lockdown as it went against the message that "all New Zealanders are united in this struggle".
The regional de-escalation plan also wasn't ready to be implemented and Ardern said they could return to that approach if a specific outbreak needed to be contained.
Bloomfield wanted schools to initially reopen with bubbles of 10 children, moving to bubbles of 20 if it went smoothly.
The Education Ministry was working with schools on how a return would work, including cleaning classrooms and assigning children into bubbles.
Three-phase communication strategy
Officials developed a three-stage strategy to communicate the move: to first "signpost" what it would look like, "prepare" people for the change then "implement", which would focus on compliance.
Moving out of lockdown would require a greater reliance on voluntary compliance and would require changes to legislation to ensure it could be enforced.
This resulted in the Covid-19 Public Health Response Act 2020, which was passed just before New Zealand moved into alert level 2.
Impact on fundamental human rights
The restrictions imposed at levels 3 and 4 involved "the most significant and widespread interference with human rights in New Zealand in living memory".
Human rights New Zealanders sacrificed were:
• Restrictions on gatherings could limit the right to manifest religion or belief in worship, observance, practice or teaching, particularly in community with others.
• Restrictions on gatherings limit the right to peaceful assembly
• Travel restrictions, domestically and at the border and the nationwide enforced quarantine order limited freedom of movement
• All measures had the potential to limit the right to be free from discrimination because of their potential disproportionate impact on some groups, particularly people of faith, Māori, Pacific peoples, older people, people with disabilities and women.
• Restrictions on gatherings could limit the rights of ethnic, religious or linguistic minorities to enjoy the culture, to profess and practice the religion, or to use the language, of that minority.
• The enforced quarantine of new arrivals in specified managed facilities may amount to an arbitrary detention and limits the rights to freedom of assembly, association and movement.
The restrictions also limited the international human rights to work, the highest attainable standard of mental and physical health and education.
The only reason limiting these rights was not unlawful was if they were a "proportionate response to the objective of protecting the public health and lives of New Zealanders", the paper said.
Impact on women and disabled people
At the time of the decision on April 17, the extent of the impact of Covid-19 on women was unclear but ministers knew police investigations into family harm significantly increased in the first week of lockdown.
And since the start of lockdown, people seeking help from refuges increased - both indications of issues that disproportionately affect women.
The disabled community remained anxious about Covid-19 as a proportion of disabled people were at a greater risk to the virus.
What Cabinet decided
After the lengthy paper from Ardern, Cabinet decided to follow Bloomfield's advice and move to alert level 3 for two weeks from 11.59pm on Monday April 27 after Anzac weekend.
This would be reviewed no later than May 11.
Ministers also agreed unless and until management of the virus was better seen as a regional priority, there would be no difference in alert levels between regions.
It also noted the response to Covid-19 continued to be the Government's highest priority.