Explained: The difference between coronavirus alert level 4 and state of emergency

When news broke on Tuesday that New Zealand's state of national emergency would be extended by a week, many Kiwis assumed that meant our coronavirus lockdown period would now be five weeks long.

But the lockdown, a measure imposed by the Government under the fourth tier of its new alert level system, has a completely different function to Civil Defence's state of emergency.

States of emergency have been declared dozens of times since the legislation was enshrined in the Civil Defence Emergency Management Act 2002 - most notably in response to extreme weather events and the Kaikoura earthquake.

In contrast, New Zealand's alert level system was only conceived last month, in response to the coronavirus pandemic.

In light of the uncertainty surrounding the functions of the two systems, Civil Defence director Sarah Stuart-Black took time in her COVID-19 update on Wednesday afternoon to point out the differences.

"I'll try and explain: the state of national emergency and COVID-19 alert levels are two distinct and separate things," she began.

"The alert levels specify the range of measures that we are taking against COVID-19. A state of national emergency provides the people managing the response in an emergency - and in this case, COVID-19 - access to powers that they need, but would not normally have.

"The alert levels can be applied without a state of emergency, and a state of emergency can be declared without alert levels being used."

In short, the alert levels are the measures deployed to protect New Zealand from COVID-19, while a state of emergency gives officials the power to enforce those measures.

"These powers are complementary to the powers under the health legislation," Stuart-Black continued.

"They have been used a number of times so far, including to stop people doing non-essential activities and to requisition a car park so it can be used as a community-based assessment centre."

Earlier in the press conference, officials revealed New Zealand had 61 new cases of coronavirus, bringing the total to 708 cases.

So far, there has been one death. Fourteen people are in hospital, two of which are in intensive care.