CANBERRA, Australia - Australia's government told the High Court on Tuesday that it should not take a constitutional ban on dual citizens being elected to Parliament literally as it decides on the fates of seven lawmakers, including the deputy prime minister, whose administration's slender majority is threatened by the crisis.

The remarks came at the start of what is expected to be a three-day hearing that will decide whether the seven should be disqualified from Parliament.

If the court rules that Deputy Prime Minister Barnaby Joyce was illegally elected in July last year due to New Zealand citizenship he unknowingly inherited from his father, the ruling conservative coalition could lose its single-seat majority in the House of Representatives, where governments are formed.

Joyce could stand in a byelection, having renounced his Kiwi citizenship. But with the government unpopular in opinion polls, voters in his rural electoral division could take the opportunity to throw both the deputy prime minister and his administration out of office.

Solicitor-General Stephen Donaghue told the High Court judges that five of the lawmakers caught up in the crisis, including Joyce and two other government ministers, should not be disqualified from Parliament for breaching the constitution because they did not voluntarily acquire or retain citizenship of another country.

A clause in the 116-year-old constitution says "a subject or citizen of a foreign power" is not eligible to be elected to Parliament.

Donaghue, however, argued that the clause "cannot be read literally."

"If a person is not aware either that they are a dual citizen or of a significant prospect that they are, in our submission by definition that person cannot have a split allegiance," he told the court.

Bret Walker, a lawyer for Joyce and fellow Nationals party minister Fiona Nash, told the court that neither knew until recently that they were dual citizens of New Zealand and Britain, respectively.

As soon as they found out, they took all reasonable steps required to sever their foreign ties, Walker said.

"There's no split allegiance where you're not aware of one," Walker told the court. "You cannot heed a call you cannot hear."

Apart from Joyce, the lawmakers under a cloud are senators who could be replaced by members of the same party without elections that could alter the balance of political power.

Donaghue argues that only New Zealand-born Scott Ludlam and India-born Malcolm Roberts should be disqualified for failing to take reasonable steps to renounce their dual nationalities.

Ludlam accepts that view and has resigned. A fellow member of the minor Greens party, Larissa Waters, has also resigned and argues that she deserves to be disqualified over her citizenship of Canada, where she was born.

Roberts argues that he shouldn't be disqualified because he had emailed the British government to renounce the citizenship he inherited from his Welsh father, but did not pay the required renunciation fee. Roberts is a member of the minor One Nation party.

Tony Windsor, a political rival of the deputy prime minister who contested the same electoral division in the last election, told the court that Joyce should be disqualified because he had known his father was born in New Zealand and should have checked his own citizenship status.

Donaghue told the seven judges hearing the case that when the Australian constitution took effect in 1901, no other country in the British Empire banned dual nationals from becoming lawmakers.

News from © The Associated Press, 2017