Key points:
- Ten politicians have been forced to resign over dual citizenships
- Two have already returned: Barnaby Joyce and John Alexander
- One more Labor MP, Katy Gallagher, has already been referred to the High Court and is awaiting a hearing
- Labor and the Coalition both want a handful more referrals this year, but cannot agree on a process
What’s the issue again?
Millions of Australians hold dual citizenship with a foreign country.
That’s fine unless you’re planning to run for federal parliament.
Dual citizenship makes you ineligible to sit in Australia's parliament under Section 44(i) of the constitution, so candidates are required to renounce their foreign ties before they contest an election.
What was all that noise last year about?
In July last year, Greens senator Scott Ludlam suddenly resigned.
He had discovered a latent New Zealand citizenship, left over from the country he had left as a young child.
That sparked a massive witch-hunt for dual citizen politicians, as journalists and political operatives scoured the ranks of every party looking for potentially invalid members of parliament.
It turns out Mr Ludlam and the Greens were not alone.
Months of accusations culminated in a landmark High Court trial of seven politicians from across the political spectrum – the so-called 'Citizenship Seven'.
Only were allowed to stay – LNP senator Matt Canavan and crossbench powerbroker Nick Xenophon – while five, including the deputy prime minister Barnaby Joyce, were ejected from parliament.
Down the line there were more resignations to come as more and more politicians were implicated: Liberal MP John Alexander, Tasmanian independent Jacquie Lambie, the NXT’s Skye Kakoschke-Moore and Liberal Senator Stephen Parry.
Then Labor MP David Feeney became the , resigning after failing to find the adequate paperwork to prove his UK citizenship was no longer in effect.
Many of the senators have already been replaced with the next candidate on each party’s senate tickets in the 2016 election.
But for the two Lower House members – Barnaby Joyce and John Alexander – the court’s ruling triggered by-elections in their local seats.
Both men were re-elected, securing the Turnbull Government’s slim one-seat majority in the House of Representatives.
Who is in danger now?
Labor senator Katy Gallagher was referred to the High Court last year and is still awaiting a High Court decision.
But there could be many more cases to come in the citizenship saga.
Defence industry minister Christopher Pyne has warned the government may use its majority in the House to refer as many as four more Labor MPs to the High Court over alleged dual citizenship issues.
Mr Pyne said there were four more opposition MPs who should resign or submit their cases to High Court judgement: Susan Lamb, Justine Keay, Josh Wilson and Emma Husar.
The Coalition is focusing its attack on Susan Lamb, who wrote to the UK government in an attempt to renounce her foreign citizenship but never received a confirmation.
Labor wants the two major parties to come together and refer batch of pollies to the High Court. The opposition is focusing most of its attention on Liberal MP Jason Falinski but claims other politicians also have questions to answer.
The opposition that would have sent four Coalition members, four Labor members and one from Nick Xenophon’s team to the High Court. The Coalition narrowly succeeded in voting the bill down.
Didn’t the government have a solution to this?
The government and Labor voted together to set up a citizenship register last year, forcing every MP and senator to they had in their possession.
But the disclosure scheme threw up as many questions as it did answers. It gave both major parties new ammunition to accuse their opponents of failing to meet their constitutional obligations.