Alice Udale-Smith, News Reporter
A court in Australia is meeting to decide whether seven politicians should be barred from public office after it emerged they all held dual citizenship.
But how did the row over citizenship start and what does the court case mean for the country? Here’s what you need to know:
:: Tap through the pictures above to see more about each case
When did the scandal start?
The controversy started in July when senator Scott Ludlam resigned because he discovered he was dual citizen of Australia and New Zealand.
Three days later another senator, Larissa Waters, discovered she still held Canadian citizenship and also resigned.
As a result of the sudden national interest, politicians from across the country started doing some digging into their own family history.
It subsequently emerged that five more politicians were also dual citizens.
The seven politicians came from across the political spectrum and were citizens of New Zealand, Canada, Italy and the UK.
Why is dual citizenship a problem?
It isn’t, unless you want to be a national politician.
Section 44 of the Australian constitution bars dual nationals from sitting in Australia’s parliament.
The constitution bans anybody who is “a subject or a citizen or entitled to the rights or privileges of a subject or a citizen of a foreign power”.
But the government is expected to argue that section 44 shouldn’t apply if people genuinely didn’t know they were dual citizens when they stood for office.
They’ll suggest that only the election of Malcolm Roberts and Scott Ludlam should be found invalid, and that the other five should be let off.
Is it really possible to not know you are a dual citizen?
According to the politicians affected, yes. And the problem is particularly prevalent in Australia.
In 2015 around 28% of people in Australia were born overseas, according to the Australian Bureau of Statistics.
Figures from the OECD show that 45% of people in the country have at least one parent who was born overseas.
The result is that many Australians have inherited citizenship from their parents without ever being aware of it.
Other people assumed that when they became Australian citizens (often as young children) this would have ended their old citizenship.
But in many cases it did not, meaning they have unknowingly been dual citizens ever since.
What does the High Court case mean for Australia?
The High Court hearings could have far reaching consequences for Australian politics.
Most importantly they could remove the ruling coalition’s majority in the House of Representatives.
The Liberal-National coalition currently has a one person majority, which they will lose if the court rules Barnaby Joyce is illegible to serve as an MP.
A by-election would have to be held to fill the deputy prime minister’s New England seat, which could trigger a full national election if it changes party.