THE Turnbull Government has admitted Deputy Prime Minister Barnaby Joyce and Nationals senator Matt Canavan were dual citizens when they were elected.
In a submission to the High Court today, Solicitor-General of the Commonwealth Stephen Donaghue said the government had received legal advice that Senator Canavan and Mr Joyce "are, or were, citizens of Italy and New Zealand respectively".
The submission also discloses that the government will pay the costs of the five federal politicians referred to the High Court "to assist in the expeditious hearing of the references".
That includes Mr Joyce, Senator Canavan, Greens senators Scott Ludlum and Larissa Waters, and One Nation Senator Malcolm Roberts.
Attorney-General George Brandis has called on the High Court to hear the five cases together in less than four weeks on September 13 and 14.
Senator Brandis also asked that the High Court require each of the politicians to file an affidavit by September 1 which shows the date and place they were born, the date and place their parents were born and the date and place their grandparents were born, if relevant.
They would also be required to show when they, their parents or their grandparents immigrated to Australia, became Australian citizens and when they renounced any foreign citizenship.
The affidavit would also include the date and under what circumstances they "became aware that they are, or may be, a citizen of a nation other than the Commonwealth of Australia", along with the details of any formal interactions with that nation, such as applying for or using their passport, voting in their public elections, or renouncing their citizenship.
The Attorney-General has also called on the court to order each of the referred politicians to provide "all documents in their possession, custody or control that relate to their citizenship status".
He recommended the court make provision for obtaining the documents by other means if they did not.
The High Court will hold a directions hearing for the five politicians on Thursday.
The Attorney-General has urged the High Court to deal with the matter "as quickly as possible" and before the full court.
"There is a compelling public interest in the references being determined as quickly as possible, given that they involve the qualifications of several sitting senators and a member of the House of Representatives, and that the judgement of the Court may have direct implications for the qualifications of two more senators (Senators Fiona Nash and Nick Xenophon) who have confirmed that they are dual citizens," the submission says.
Both Senators Nash and Xenophon will refer their dual citizenship cases to the High Court when Parliament returns on September 4.
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