Legislation that will curtail freedoms of hundreds of thousands of unvaccinated New Zealanders has been passed under urgency amid outrage from Opposition MPs that it has avoided normal levels of scrutiny. 

The new laws will allow businesses and groups to introduce vaccination mandates among their staff ahead of the new Covid-19 Protection Framework starting in December. 

Along with those already in force, including health and education workers, it means mandates will cover about 40 per cent of the workforce. 

This framework, also known as the traffic light system, includes requirements for workforces deemed high risk to be vaccinated, including hospitality, events, gatherings, close-contact businesses and gyms. 

Mandates and the ability of businesses to use them have wide parliamentary support, but the traffic light system and speed with which the legislation has been pushed through has drawn major criticism from all sides, with National, Act and Te Pāti Māori all opposing. 

Legislation has to be in place before the traffic light system comes into force, but passing it under urgency, which the Labour Government can do with its majority, also means it bypasses normal levels of scrutiny, including from select committees and public submissions. 

National's Covid-19 spokesman Chris Bishop said it was one of the "most significant" Bills and yet would become law within 24 hours of being introduced. 

"This is contemptuous of Parliament, contemptuous of the people of New Zealand, contemptuous of the rule of law," Bishop said during the third reading. 

Labour also rejected a motion to have a post-enactment review of the law, which was supported by all other parties. 

Bishop said he was unsure if the law would actually give the Government the powers it sought, potentially opening it up to legal challenges. 

Bishop said it was not that some of the aspects were not justified - National generally supports mandates - but that the laws proposed needed more time and scrutiny, citing comments from Government legal advisors over the short timeframe. 

Covid has been in the community since August, and since the elimination strategy failed the Government had no back-up plan, Bishop said. 

He feared the "secretive" and "non-transparent" way the Bill was being rammed through could further fuel division. 

"This Bill will backfire on the Government. It will not help." 

Te Pāti Māori co-leader Debbie Ngarewa-Packer said it was a "cruel Bill" and "tramples on tikanga". 

Ngarewa-Packer said they were concerned about a lack of consultation with Māori and if it was consistent with Te Tiriti o Waitangi. 

Even Speaker Trevor Mallard criticised the use of urgency, particularly given the policy around the framework became public on October 15. 

"The policy decisions, the drafting instructions, or an exposure draft of the bill could and should have been made public and preferably considered by a select committee, either through reference through the House or using committees' inquiry functions. 

"The failure for that to occur is primarily the Government's responsibility. 

"Urgency of this type used to be common. It isn't any more, for good reason; it resulted in bad law." 

Introducing the Bill, Covid-19 Response Minister Chris Hipkins said the measures were "justified given the situation that the pandemic and the public health response requires". 

"They'll help us to better manage the public health risks that are caused by those who haven't been vaccinated, because the reality is, now, the key thing to bringing greater freedoms for us all is to encourage those people to be vaccinated." 

Prime Minister Jacinda Ardern said the Government was not abusing its power by rushing through the Bill. 

"Without these provisions we would not have the ability to ease restrictions and into the new framework." 

On the lack of detail in the Bill, Ardern said they had used orders throughout the response as it allowed restrictions to be lowered more quickly than the full legislative process. 

Among those criticising the Bill have been the Human Rights Commission and legal experts - Victoria University law and governance expert Dr Dean Knight calling it a "constitutional disgrace". 

They were concerned about human rights implications and consistency with Te Tiriti, and called for mechanisms to review the legislation. 

The Council for Civil Liberties has also called out the process, revealing the Government has refused to release advice it received around vaccination certificates until January. 

"The failure to be open and straightforward with the public reflects poorly on a Government that likes to boast about high levels of public trust, and how transparent it is," chairman Thomas Beagle said. 

Workers covered would need to have a first dose by December 3 and a second by January 17. Non-compliant businesses could be fined up to $15,000. 

The changes will also require employers to give workers time off to get vaccinated, and a four-week notice period for those who lose their jobs because they were not vaccinated. 

With still about 8 per cent of the eligible population yet to receive a dose of the Pfizer vaccine, potentially hundreds of thousands of workers could be affected once the framework kicks in on December 3. 

Polls have shown strong support for vaccine mandates, but have also shown confusion around the new traffic light system. 

A tool to help clarify what work should be covered by vaccinated workers and for assessing when it is reasonable to require vaccination for other work has also been developed. 

The four criteria, at least three of which must be met, are: the size of the workspace, how close people are to others, how long they are near to others, and whether they provide services to people vulnerable to Covid-19.