CROSSBENCHERS are ramping up a push for a full citizenship audit of Parliament following issues raised by Senator Derryn Hinch.
Senator Hinch yesterday admitted that until last year, he had been receiving a US pension of about $600 a month since 2013.
He has written to the Solicitor-General amid concerns he could be in breach of section 44 of the Constitution.
The 73-year-old wrote to US Social Security Administration after he was elected to the senate last July, asking for the payments to stop.
One Nation Senator Pauline Hanson used the issue to renew calls for a full citizenship audit.
"If Malcolm Turnbull wants to clean up the corrupt unions he should lead by example and clean up this citizenship fiasco first," Senator Hanson said.
Meanwhile, board appointments made by Deputy Prime Minister Barnaby Joyce, including that of former senior National Ron Boswell, could be under a cloud if he is found to have been ineligible at the time.
Opposition agriculture spokesman Joel Fitzgibbon warned if the "jobs for the boys" appointments were made while Mr Joyce was ineligible to be a minister, they could be targeted.
He pointed specifically to Ron Boswell, who was appointed chair of the Fisheries Research and Development Corporation, and former NSW Nationals MP Kay Hull, who was appointed to the Rural Industries Research and Development Corporation.
"I think they would be very vulnerable in all this," Mr Fitzgibbon said.
"All those appointments could come under question if (Mr Joyce) is not eligible."
Prime Minister Malcolm Turnbull yesterday repeated that he was confident Mr Joyce, as well as Senators Fiona Nash, Matt Canavan and Nick Xenophon, would survive High Court challenges to their parliamentary eligibility.
"But Mr Fitzgibbon needs to explain if he has satisfied himself if appointments under a hypothetical Labor government led by Bill Shorten would be legal, given his refusal to level with voters by releasing his own citizenship documents," he said.
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