BBC Live
https://www.bbc.co.uk/news/live/world-australia-59909477
Specifically the power under s116 (e)(i) of the Migration Act.
It allows the government to cancel someone's visa if they present a risk to "the health, safety or good order of the Australian community..."
The ABF decided that Djokovic, being unvaccinated, posed such a threat.
However, the tennis star's lawyers argue that he presented "miniscule" risk, given he had already had Covid, reducing his risk of contracting it again and passing it on to others.
Australia is already in the grip of an Omicron wave and seeing over 90,000 cases a day. Djokovic's entry hardly makes any difference, his lawyers said in their court documents.
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