The leader of the Australian Greens, Richard Di Natale, addresses the media last month in Sydney. (Dan Himbrechts/European Pressphoto Agency)

Richard Glover is an Australian writer and broadcaster.

Is a Greek person always Greek? That might sound like a philosophical question fashioned in an era of identity politics, but in Australia right now, it’s a matter of political life-or-death.

A sudden focus on dual citizenship is cutting a swath through the Australian parliament. Already, two senators have been forced to resign. And the resources minister has quit the prime minister’s Cabinet, his career hanging in the balance.

Some say the issue could bring down the government. It may come down to just one vote by liberal MP Julia Banks, who could be Greek — sort of. We’ll come back to her.

All of this seems bizarre in a country in which about a quarter of the population was born in a different country. In fact, if you include people with parents born overseas, then nearly half of all Aussies have a recent link to somewhere else.

The recent crisis is due to a clause in the Australian constitution that forbids dual citizens from standing for election. According to Section 44, a person is ineligible to stand for Parliament if he or she has any “allegiance, obedience, or adherence to a foreign power.”

But here’s the problem: What if politicians have an additional citizenship that they weren’t aware of?

Oddest of all is the story of Matt Canavan, a rising star on the conservative side of politics. He recently resigned from his leadership position — confessing that his mother, many years ago, had applied for Italian citizenship on his behalf. Canavan had, on his own evidence, signed no papers. The action was taken without his knowledge. He says he has never even been to Italy. It was his mother’s decision, taken unilaterally. Blame her.

The best response to the mess came from the leader of the Australian Greens, Richard Di Natale, himself a person of Italian heritage, who said, “If you’re a genuine Italian … you never blame your mum for anything. So that might be his only defense in this case, I reckon.” While Di Natale’s comment was witty, it was delivered in the face of real political pain. He’d just lost his two best performers to the same “dual-citizen” rule.

Indeed, it was the Greens who kicked off the citizenship crisis — when the party’s deputy leader, Scott Ludlam, realized he still held New Zealand citizenship. Oops.

Ludlam — who is handsome, charismatic and social-media-savvy — had assumed his Kiwi citizenship had been automatically extinguished when he became an Australian in his mid-teens. Not so, it turned out, as the rules for relinquishing differ from country to country.

Next to go was his fellow deputy — Senator Larissa Waters, who won international praise after breastfeeding her baby while addressing parliament. Soon after Ludlam’s problems, Waters checked her own status and tearfully confessed that she was a Canadian. Waters was born in Canada — but to Australian parents who’d returned home when their child was just 11 months old. She’d never returned to the country. According to the legal advice Waters received, a change in Canada’s laws, made just one week after she had been born, meant Canadian citizenship has to be actively renounced.

Waters is not the only one to find herself in confusing territory. Sam Dastyari, a Labor senator, was born in Iran — a country whose citizenship is hard to renounce. He has been on social media recently, noting the amount of money it took to free himself:

Everyone talking about Larissa and Scott. To put everyone at ease. I was born in Iran (hence born an Iranian citizen). I…

Posted by Sam Dastyari on Monday, July 17, 2017

A flurry of other Parliament members found themselves racing to share proof they were totally, unimpeachably Australian.

The list even included former prime minister Tony Abbott, still a parliamentarian, who used Twitter to publish a letter he’d had from the Brits, accepting that he’d departed the flock.

Which brings us to back to Banks. She has done nothing to renounce her Greek citizenship — mainly because she doesn’t accept that she has it.

Banks has a point — she’s really not Greek in any meaningful way. Yet others claim Greek citizenship would have been automatically conferred via her father. They say Greek citizenship is automatic, and you have to specifically renounce it. Yet if she goes, our prime minister might follow. The government could change because of a Greek woman who didn’t know she was Greek.

So what now? Canavan, having resigned his Cabinet post, plans to take his case to the High Court. He, no doubt, hopes that “my mother did it” will be enough to convince the judges.

The two Greens, meanwhile, have both taken it on the chin and resigned. The Greens now want an official vetting process that would address the eligibility of all parliamentarians — an that idea has sent a shiver through the rest of the Parliament  — 23 of whom were born overseas.

How can one prove someone is a genuine Australian? We may have to require everyone to eat a meat pie, sink a beer and throw a shrimp on the barbie.

Then again, that would be a strange outcome in a country that prides itself as a special place: somewhere you can flourish wherever you were born.