Barnaby Joyce, a member of the Australia Federal Senate, talks during an interview in Canberra, December 2, 2005.
Barnaby Joyce, a member of the Australia Federal Senate, talks during an interview in Canberra, December 2, 2005. Reuters/Tim Wimborne

Deputy Prime Minister Barnaby Joyce and other “citizenship seven” MPs have received verdict on Friday. The court ruled that Joyce and four other politicians were wrongly elected due to dual citizenship.

The High Court of Australia decided that some politicians are disqualified from office. Joyce’s exit cost the government its one-seat parliamentary majority and forced a by-election. Some already quit in July.

Joyce, Fiona Nash, Scott Ludlam, Larissa Waters and Malcolm Roberts deemed "a subject or a citizen of a foreign power.” They were therefore incapable of being chosen or sitting as a senator or a member of the House of Representatives.

Matt Canavan and Nick Xenophon were ruled to have been validly elected. They were not dual citizens, according to the constitutional definition.

The court was not convinced that Canavan had attained Italian citizenship through descent. As for Xenophon, his inherited UK citizenship did not give him full rights. Canavan will be returned to cabinet as Resources Minister and Minister for Northern Australia, the Sydney Morning Herald reports.

According to Australia's constitution, dual citizens could not be elected. The dual citizenship issue has hit Australian politics since July, which prompted several MPs to clarify their status to the public.

Joyce's exit strips the government of its one-seat majority. He could return via a by-election. There is a possibility that Australian Prime Minister Malcolm Turnbull would regain his 76-seat majority if Joyce wins the by-election on December.

Joyce said he respect the court’s verdict. "We live in a marvellous democracy, with all the checks and balances they have given us all the freedoms we see- I thank the court [for] their deliberations,” he said, according to the BBC. He said he would stand in the by-election, telling reporters in the rural town of Tamworth that politics is a tough game. He added that one takes hits and sacrifices.

The Australian dollar has dropped a quarter of a US cent following the court announcement of its ruling. It ordered that Joyce should seek a new mandate in his rural New South Wales state electorate. Meanwhile, the Australian prime minister should win the support of one of three independent lawmakers to keep his minority government afloat.

All seven lawmakers have recognised that they were dual nationals when elected last year. However, they argued they were initially not aware of their status. Some were conferred a second nationality by birth, some by descent.