The government is still working out what 'mandatory' will actually mean when it comes to the roll out of vaccine certificates next month.
Israeli men show 'green passes; or vaccine passport at event in Tel Aviv (file image). Photo: AFP
Lawyers suggest the certificates could face a legal challenge for breaching a person's human rights, but employers also have an obligation to protect their staff and patrons.
According to sources who have been working on the vaccine certificates, there are three possibilities for how they will be legally enforced.
An individual who wants to access an event, or possibly a restaurant, bar or other business, could be liable if they don't produce a vaccine certificate.
They could face a fine, for instance, if they do not prove their vaccination status.
A second option is to hold event organisers or businesses to account if they do not scan the health passes, much like the way businesses are liable if they sell alcohol to someone who is under age.
The manager, owner or event organiser could then be fined.
The third option is that event organisers or businesses only have to have the ability to scan a vaccine certificate, but there would be no mandate that they actually scan the passes.
This is the current situation with the 'mandatory' scanning rules, where a business is not punished if a patron does not scan in.
They also have no obligation to refuse the person service.
Michael Dreyer, who is leading the vaccine certificate work at the Ministry of Health, told RNZ officials were still working through what mandatory vaccine certificates will actually mean, a month out from their launch.
"We are consulting with business, hospitality and the events sector on the finer details of how the vaccine certificate can work on the ground," Dreyer said.
"We're still working through the policy settings for exactly which types of events a proof of vaccination will be required."
The reason it was a legally murky area was because vaccine certificates would be a breach of a person's human rights.
In New Zealand's Bill of Rights Act, people can not be discriminated against based on their health status.
A mandatory vaccine certificate to access events or businesses would do exactly that.
It helped explain why the government was not considering implementing the health passes in places like supermarkets, health facilities, or churches.
People have the basic human right to use those sorts of facilities.
However, other laws we have also breach human rights, but are deemed to be for the greater good.
One example is breath testing by the police.
Technically, it breaches your human rights to be forced by police to blow into a tube and show your breath alcohol.
But by doing it the police are able to crack down on drunk drivers and reduce the number of serious crashes and road deaths.
There will be a similar argument for vaccine certificates.
Employers also have an obligation to keep staff and customers safe from a health and safety perspective, and barring people who are not vaccinated could fall within that scope.