The Tasmanian crossbench senator has resigned after her office received confirmation from the UK Home Office she is a dual citizen.
- Lambie resigns over her UK dual citizenship
- Says she hopes to return to parliament 'one day'
- Potential Lambie Network replacements may also face Constitutional problems
- Eight federal politicians have now been ruled ineligible to serve under Section 44
Tasmanian crossbench senator Jacqui Lambie has resigned from the Senate, becoming the eighth federal politician to fall victim to the ongoing dual-citizenship saga.
Senator Lambie announced the news on a local Tasmanian radio station on Tuesday morning, revealing the UK Home Office had confirmed she held UK citizenship.
She formally announced her resignation on Tuesday afternoon in a tearful speech to the Senate chamber that listed a number of her legislative achievements on the crossbench.
"I am sad I could not achieve everything I wanted to achieve. It is my greatest disappointment in my time here," Senator Lambie said. "There's so much more I wanted to."
She said her proudest achievements included blocking government cuts to welfare, securing funding for Tasmanian schools, negotiating a Defence Force pay deal and supporting the expansion of hydropower in her home state.
The UK Home Office confirmed Senator Lambie's grandfather and her Scottish-born father were both UK citizens and had never renounced their status, according to the senator, meaning she was also a UK citizen by descent.
"Anyone who knows my father will be shocked to think of him as anything other than Aussie," she said.
"I love my father to death and I do not blame him for this. He has done nothing for which to apologise and he has been my strongest supporter, my loudest cheer squad and my closest advisor."
"It is not because of him that I am leaving this place. It is because of him that I am here in the first place."
Lambie flags potential come-back
Senator Lambie said she did plan to return to parliament "one day".
Her replacement in the Senate will be decided in a recount, but she could recontest at a future election.
On Tasmanian local radio, she suggested she may run for a Lower House seat if Labor's Justine Keay also finds herself ejected by Section 44.
The Coalition is calling for Ms Keay to be referred to the High Court and has threated to use its numbers to force the issue, with or without Bill Shorten's consent.
Section 44 toll continues to rise
Dual citizens are not allowed to serve in the Australian parliament under Section 44(i) of the Constitution, which has now forced eight federal politicians to quit.
A High Court hearing into the matter in October found the deputy prime minister Barnaby Joyce was elected in breach of the Constitution.
The Turnbull Government is now facing two by-elections in the Lower House: one for Mr Joyce in New England, and another for John Alexander in Bennelong, who has also quit over a latent dual citizenship.
Last week, Jacqui Lambie said she did not believe she was dual citizen. "I am proud of my Scottish ancestry and my father is too," she said at the time.
"I'm happy to put on record that I'm satisfied that my parents are both Australian citizens and I have no concerns about me being a dual citizen because of where they were born or came from."
Tasmanian Liberal Senator Eric Abetz said Senator Lambie had "acted with integrity" by resigning, and said she had brought some "interesting flare" to the chamber in her time.
Senator Lambie had promised to resign if she found she held UK citizenship, amid mounting pressure in the Senate on Monday.
Australian Conservatives leader Cory Bernardi hinted another Senate colleague could be in breach of the constitution.
"I do have concerns that there is a member of this chamber, at least one, who knows they are not eligible to be here because of their constitutionality," Senator Bernardi told the chamber.
Lambie replacements face Constitutional questions of their own
As with the other recently disqualified senators, Senator Lambie's position would normally go to the next person on her Jacqui Lambie Network ticket in the 2016 election, following a recount.
But the next person on the party's list may not be able to replace her.
A constitutional expert told AAP on Monday there are doubts around Senator Lambie's possible replacement, Devonport Mayor Steve Martin.
Professor George Williams, from the University of NSW, said Mr Martin could be in difficulty because of his local government position.
Whether a local council position is an "office of profit under the Crown" - a ground for disqualification under the constitution - has been a grey area in constitutional law.
"The High Court would need to decide," Prof Williams told AAP.
The next person on the ticket, Rob Waterman, is CEO of Rural Health Tasmania
Rural Health Tasmania's annual report for 2017 said it received funding from several federal government programs run by the departments of health and social services.
That could also constitute an office of profit under the Crown.
- with wires