Workplace authorities say only very few businesses will be able to force their workers to get the COVID-19 jab as Australia prepares to roll out the vaccine.
The Fair Work Ombudsman on Friday said it had fielded questions from employers about what they could and couldn't do when it came to workers getting the jab.
It emphasised that "the overwhelming majority" of Australian employers should assume they wouldn't be able to mandate the vaccine.
It said businesses essentially only could if there was some specific law that required a worker to be vaccinated, or if they had an agreement or contract with a worker that stipulated they had to get vaccinated.
"There are currently no laws or public health orders in Australia that specifically enable employers to require their employees to be vaccinated against coronavirus," the ombudsman said.
Health Department Secretary Brendan Murphy on Thursday flagged that the government hadn't ruled out eventually making COVID-19 vaccinations mandatory for workers in aged care facilities.
The ombudsman said that, in lieu of a contract or law, employers could give their workers a direction to get the jab - but only if that direction was "lawful and reasonable".
"On its own, the coronavirus pandemic doesn't automatically make it reasonable for an employer to direct their employees to be vaccinated against coronavirus," the ombudsman said.
It said it might be reasonable for employers to direct their workers to get a COVID-19 vaccine if they, for example, worked in hotel quarantine or border control and interacted with people who were at an "elevated risk" of being infected with coronavirus.
The ombudsman said it might also be reasonable for an employer to direct employees to get the jab if workers had close contact with people most vulnerable to the virus, like elderly or sick people.
It said that, if a business was ultimately allowed to direct or require employees to get the jab and a worker refused, they could reprimand them through disciplinary action.
However, it said: "Stand downs are unlikely to be an available option for employers if an employee refuses a direction to be vaccinated."
The ombudsman said that employers could ask workers to show them evidence that they had been vaccinated, and, in most circumstances, businesses could require prospective employees to get the COVID-19 jab.
The ombudsman said businesses should get legal advice if they wanted to try to compel employees to get vaccinated.
Attorney-General Christian Porter said the guidance, which was backed by Safe Work Australia, reinforced the federal government's broad stance that "vaccination should be voluntary".
"As the Prime Minister has said many times, the government expects that the overwhelming majority of Australians will want to be vaccinated to protect themselves and their loved ones, and so they can get on with their lives without disruption," Mr Porter said on Friday.
He said the guidance on how businesses should handle the vaccine rollout had been developed after talks with employers and unions.
ACT and federal public servants have been told the vaccine won't be a requirement.
The Australian Chamber of Commerce and Industry said it supported the national cabinet's stance that COVID-19 vaccines should be voluntary.
Prominent ACT human rights barrister Allan Anforth told The Canberra Times that it would be easiest for workplaces to be able to compel their workers to get the COVID-19 vaccine if the government amended legislation.
"The Parliament could just simply amend the Public Service Act or the ACT Public Sector Management Act, whatever the statute is, and make it compulsory," he said.
"The only way you could strike down such federal legislation would be on constitutional grounds, and it wouldn't be unconstitutional."
Mr Anforth said employers had a legal and ethical duty to protect their workers from anyone who had an infectious disease.
He said that legal obligation allowed employers to instruct infected employees not to attend work, unless they could prove they were no longer infected.
The first Canberrans to get the COVID-19 vaccine will have it administered at the Garran Surge Centre on Monday.
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