Matt Canavan quits cabinet over Italian dual citizenship

The resources minister Matt Canavan has quit the cabinet because he is a dual citizen of Italy.

Canavan’s resignation on Tuesday night follows the recent resignation of two Greens senators, Larissa Waters and Scott Ludlam, because of dual citizenships – a controversy that has triggered questions about the eligibility of many other Australian parliamentarians.

Canavan told reporters on Tuesday night his mother had applied for Italian citizenship on his behalf without his knowledge or consent when he was 25 years old, in January 2007.

He said he had “no suspicion” he was in possession of a dual citizenship until last week, when his mother “raised the possibility”. The Italian embassy subsequently confirmed he was a citizen of the country.

“I was not born in Italy, I have never been to Italy and to my knoweldge I have never set foot inside the Italian consulate or embassy,” Canavan said.

“I knew my mother had become an Australian citizen, but I had no knowledge that I myself had become an Italian citizen, nor did I request to become an Italian citizen”.

The attorney general, George Brandis, said preliminary legal advice to the commonwealth suggested there had been no breach of section 44 of the constitution in Canavan’s case.

Brandis told reporters given Canavan had no knowledge about his status as a dual citizen, and the “legal uncertainty” surrounding the issue, the government would refer the issue to the high court for deliberation.

Australia’s constitution bars dual citizens from eligibility for elected office, unless they can show they have taken reasonable steps to sever foreign ties.

The lack of clarity over his eligibility puts a question mark over the long term political future of one of the most prominent National party parliamentarians, a significant blow for the party and a political embarrassment for the Turnbull government.

Canavan said he was seeking advice about whether the registration of his Italian citizenship by his mother was valid under Italian law.

He said on the basis of the government’s legal advice, he would not quit politics or the parliament before the high court’s deliberations.

But Canavan said it was appropriate he step aside as minister for resources and northern Australia until the issues were clarified.

A statement issued by the prime minister on Tuesday night indicated the deputy prime minister and Nationals leader, Barnaby Joyce, would take over his portfolio responsibilities “until Senator Canavan’s status is resolved”.

Constitutional law expert George Williams told Guardian Australia on Tuesday night it would be a significant high court case, because there were no clear precedents.

Williams, who is the dean and Anthony Mason professor of law at the University of New South Wales, said if the facts were as Canavan described them, he had a “good argument”.

The constitution requires that reasonable steps be taken to sever foreign ties, “but what is reasonable when he lacked knowledge is yet to be determined”.

“It’s never been decided, so this will be a significant high court case.”

Williams said Waters may also choose, given Tuesday’s events, to test her position in the high court as well. “I think she’s got an argument about reasonableness,” he said.

The law professor said the past few weeks had opened a Pandora’s box on eligibility questions, and it was entirely possible that more cases would follow.

The departure of two of the Greens’ nine senators – and the new furore involving Canavan – also follows recent high court proceedings against two other senators, Bob Day, who represented the conservative Family First party, and Rod Culleton, another rightwing independent, after both offended constitutional provisions.

The recently departed Waters took to Twitter to commiserate with Canavan.