The opposition is doing everything it can to exploit the uncertainty surrounding the Turnbull government following the High Court's decision on citizenship. More MPs have questions to answer about whether they complied with the constitution's requirements before being elected to Parliament. Parliament returns for the final sitting fortnight of the year on November 27 and the situation is ripe for mischief making. But what does it all mean?
How many MPs sit in the Parliament and which parties do they belong to?
There are 150 members of the House of Representatives.
At last year's federal election, the Coalition won 76 seats and Labor 69.
There are also five members of the crossbench - MPs who represent minor parties or are independent. Andrew Wilkie and Cathy McGowan are independents, Bob Katter represents Katter's Australian Party, Adam Bandt the Greens and Rebekha Sharkie the Nick Xenophon Team. Ms Sharkie is one of the MPs who has been caught up in the citizenship farrago.
There are 76 senators in the Senate.
The Coalition has 27 (including Senate President Scott Ryan) and Labor has 26.
The Greens have nine senators, One Nation has three and the Nick Xenophon Team has two. Jacqui Lambie, David Leyonhjelm, Derryn Hinch, Cory Bernardi, Lucy Gichuhi and Fraser Anning fill out the crossbench. There are three vacancies but there could soon be a four if Jacqui Lambie also resigns.
How has the citizenship crisis affected the state of play?
The Coalition is down to 73 seats on the floor of the House of Representatives. One of its MPs, Tony Smith, is the Speaker which means he does not usually vote. Two of its MPs have resigned because of the citizenship saga. Former deputy prime minister and Nationals leader Barnaby Joyce is widely expected to win the byelection for his NSW seat of New England. The byelection will be held on December 2, which means Joyce will miss the first week of the final sitting fortnight of Parliament - the week beginning November 27. Liberal MP John Alexander also faces a byelection in his Sydney seat of Bennelong. It will be held on December 16, which means Alexander misses both sitting weeks.
What role does the Speaker play?
If the House of Representatives was a school then the Speaker is the principal. The Speaker does not usually vote on legislation or procedural motions. However, if there is a tied vote, by tradition, the Speaker gives the casting vote to maintain the status quo. Tony Smith could be called upon to do this because of the tight situation the Turnbull government finds itself in.
Is supply guaranteed?
Yes. Both Cathy McGowan and Rebekha Sharkie have said they will continue to support the government when it comes to supply (the money it takes to run the country) and confidence.
Why do "the numbers" matter?
Government is formed in the House of Representatives – typically by the party that holds the majority of seats, although a minority government can also be formed when one party governs with the support of independents or minor party representatives.
The opposition is likely to use the first week of the final sitting fortnight – the week beginning November 27 – to try to pass legislation on penalty rates and a banking royal commission in an attempt to exploit the Coalition's tricky situation. It has support from some members of the crossbench for both of these pieces of legislation but will seek support from Coalition MPs such as Queenslander George Christensen, who is at odds with the Coalition on these issues.
Because the government has lost two of its MPs it is vulnerable to this possibility. If the government loses these votes the opposition could move a motion of no confidence in the government. If the government lost this motion, the opposition could go to the Governor-General, Sir Peter Cosgrove, and tell him the government no longer has the confidence of the House of Representatives and ask him to dissolve Parliament and call an election.
Is this likely?
Not really, but you can't rule anything out at the moment. The opposition is running a guerilla campaign against the government by which it hopes to undermine confidence in the Coalition. Its chances of bringing down the government are, at this point, remote.
Could all of this change?
As the saying goes, a week is a long time in politics, so you never know.
Both major parties are threatening to refer more MPs to the High Court to have their citizenship status examined. Other Coalition MPs under a cloud are Julia Banks, Alex Hawke, Nola Marino, Tony Pasin and Ann Sudmalis. Labor MPs with questions to answer are Josh Wilson, Susan Lamb and Justine Keay. Katy Gallagher is also in some difficulties but she is a senator so her situation does not affect the state of play in the House of Representatives.
A relationship banned under traditional law.
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