Four MPs who were dual citizens when they nominated as candidates in the 2016 election have resigned from parliament in the wake of a High Court ruling today that declared Labor senator Katy Gallagher ineligible because she was in breach of the Constitution, forcing her from Parliament.

Three ALP MPs, Josh Wilson from Western Australia, Queensland’s Susan Lamb and Tasmania’s Justine Keay, announced they will resign and recontest their seats, along with former Nick Xenophon Team MP Rebekha Sharkie from Adelaide.

As the dual citizenship saga drags into its 10th month, leaving taxpayers with a legal bill of around $12 million to clarify whether politicians were in breach of the the Constitution, the latest resignations bring the number of MPs and senators who’ve stepped down because they were dual citizens to 15, with 10 leaving politics as a result.

Embarrassingly for Labor and opposition leader Bill Shorten, who maintained his party’s candidates were in the all clear as the saga unfolded because they’d all gone through a rigorous vetting process, four Labor MPs and a senator have now been found in breach of the Constitution.

While Wilson, Keay and Sharkie subsequently had their British citizenship revoked, Lamb remains a dual citizen because UK authorities insist she supply her parents’ marriage certificate – her father has died and she is estranged from her mother – before her revocation can be processed, which makes it unclear how she can recontest her seat.

Gallagher, a former ACT chief minister, will leave politics and be replaced by another candidate nominated by Labor after her argument to stay was rejected by the full bench of the High Court.

Gallagher’s submission that she took “reasonable steps” to renounce her British citizenship but there were processing delays. The four MPs stepping down today, who were also UK citizens at the time they nominated as candidates in 2016, but had lodged the initial paperwork to renounce it, were making the same failed argument as Gallagher.

The Constitution clearly states that a candidate cannot be a dual citizen at the time of nomination and all candidates are asked to sign documents for the Australian Electoral Commission stating they are not.

Those who’ve been forced from politics as a result of the fiasco now include Gallagher, Nationals deputy Fiona Nash, Liberal and former senate president Stephen Parry, Labor MP David Feeney, One Nation’s Malcolm Roberts, NXT’s Skye Kakoschke-Moore, Tasmanian independent Jacqui Lambie and the Greens co-deputies Larissa Waters and Scott Ludlam.

Former Nationals leader Barnaby Joyce and Liberal MP John Alexander, both resigned last year but reclaimed their seats in subsequent by-elections.

The ALP already faces a by-election in Perth following the resignation Tim Hammond, the party’s shadow minister for consumer affairs, last week because of the excessive demands of politics on his family.

Late last year, Prime Minister Malcolm Turnbull called yet another inquiry into Section 44 of the Constitution to see if changes should be made to either make it easier to renounce dual citizenship or whether the requirement should be deleted. However, any changes will need to be approved by Australian voters in a referendum.

NOW READ: SERVES THEM RIGHT: Australian MPs have talked about the dual citizenship problem for nearly 40 years – and done nothing about it

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