Six Australian senators are waiting for confirmation on whether they can continue in the country's Upper House, and the High Court will have to make rulings on each of them.
Government Senator Fiona Nash revealed yesterday she is a UK citizen by descent because of her Scottish-born father.
Australia's constitution states you cannot be a parliamentarian if you hold dual citizenship, or are entitled to it.
Ms Nash is deputy leader of the National Party, the junior partner in Liberal Party Prime Minister Malcolm Turnbull's governing coalition.
The saga has gripped Australian politics for five weeks, forcing dozens of MPs to make statements about their citizenship status, and causing two Green Party members to resign.
The furore spilled over the ditch after it emerged Australia's deputy prime minister Barnaby Joyce holds New Zealand citizenship - something he has since revoked.
It was revealed an Australian Labor Party staff member had contacted New Zealand Labour MP Chris Hipkins, who put questions in parliament about dual citizenship rules.
This led to Australian Foreign Minister Julie Bishop claiming she would find it difficult to build trust with a New Zealand Labour-led government.
Australia's dual-citizen senators
- Fiona Nash - National Party
- Deputy Prime Minister Barnaby Joyce - National Party
- Former Resources Minister Matt Canavan - National Party (Resigning ministerial position until resolved)
- Malcolm Roberts - One Nation
- Larissa Waters - Australian Greens (Resigned)
- Scott Ludlum - Australian Greens (Resigned)
- Susan Lamb
- Justine Keay
- Maria Vamvakinou
- Tony Zappia
- Senator Nick Xenophon - Party leader for Nick Xenophon Team (mother from Greece, father from Cyprus)
- Justice Minister Michael Keenan (was forced to deny he was a British citizen)
- Some others have come out and provided documentation renouncing foreign citizenship, while others may be sitting quietly hoping it blows over
Labor insists it has better vetting processes and doesn't need to refer any members to the High Court, but they won't release any documentation to substantiate this.
The Federal Government has threatened to refer:
There are also complications for:
Like Mr Joyce, Ms Nash said she would continue in her position until the High Court clarifies a section of Australia's constitution.
"I can advise honourable senators, that on the basis of the solicitor-general's advice, the Prime Minister sees no reason for me to stand aside from my portfolio responsibilities," she said.
Parliament's sitting week had ended, and it was too late for the Senate to refer her to the High Court. Ms Nash said she has had legal advice that she had not breached rules.
Prime Minister Malcolm Turnbull this week affected surety, declaring Mr Joyce was "qualified to sit in this House, and the High Court will so hold".
The Greens and independents have called for an audit of all parliamentarians, but the major parties are not interested.
Labor senator Katy Gallagher said Mr Turnbull needed to explain why he had not asked Mr Joyce and Senator Nash to stand down.
"Senator Nash's statement means the entire National Party leadership is now facing disqualification from the Parliament," she said.
"Malcolm Turnbull needs to explain why he is holding Mr Joyce and now Senator Nash to a lesser standard than Matt Canavan and not requiring them to stand down."
Senator Gallagher said it was unacceptable Senator Nash had stayed quiet about her citizenship doubts since Monday.
"As Senator Nash admitted, she has known since Monday that she was a dual citizen, yet waited until one minute before the Senate rose for a two week break to inform the Parliament," she said.
"This is simply not good enough."
What's the problem? How can the court help?
The country's High Court has its first hearing on the matter set down for 24 August, and is expected to decide by December.
The meaning of section 44(i) has not been read by the High Court as an absolute bar on a candidate being a foreign citizen.
In a ruling on a 1992 High Court case, Independent MP Phil Cleary was disqualified along with two candidates. However, that case also found that "it would be wrong to interpret the constitutional provision in such a way as to disbar an Australian citizen who had taken all reasonable steps to divest himself or herself of any conflicting allegiance".
Either way, the rules are not entirely clear, with the case also finding that what amounts to "reasonable steps" to renounce foreign nationality would depend on the situation, including the rules of those foreign powers, the individuals' connection to it, and whether they had expressly renounced their allegiance in an Australian Naturalisation Ceremony.
So now, the court must rule individually on each Senator. Presumably Ms Nash will join the other five cases once Parliament resumes.
The constitution cannot be changed without a referendum, which rarely succeed.
Australian Conservatives senator Cory Bernardi has suggested suspending the Parliament.
The Prime Minister can ask the Governor-General to discontinue the session of Parliament, but at this point it's unlikely he'd want to do that.
- BBC / ABC / RNZ