Crisis over the eligibility of members of the Parliament of Australia over citizenship
Starting in July 2017, the eligibility of several members of the Parliament of Australia was questioned. Referred to by some as a "constitutional crisis", fifteen sitting politicians were ruled ineligible by the High Court of Australia (sitting as the Court of Disputed Returns) or resigned pre-emptively. The situation arose from section 44(i) of the Australian Constitution, which prohibits parliamentarians from having allegiance to a foreign power, especially citizenship. On that basis, the High Court had previously held that dual citizens are ineligible for election unless they have taken "reasonable steps" to renounce the foreign citizenship before nomination.
Six senators and Deputy Prime Minister Barnaby Joyce MP, known as the "Citizenship Seven", were referred to the High Court between August and September in 2017. In October 2017, the High Court unanimously determined that five were ineligible to be elected as dual citizens at the time of nomination. In November 2017, three more senators resigned after recognising their dual citizenship, including Senate President Stephen Parry, as did John Alexander MP. His resignation briefly cost the Coalition government its lower house majority, until Joyce and Alexander regained their seats in by-elections.
Following publication of a register of parliamentarians' citizenship status in December 2017, Senator Katy Gallagher and David Feeney MP were referred to the High Court. Feeney resigned in February 2018, before his case was heard. In May 2018, the High Court ruled that Gallagher was also ineligible, thereby clarifying the "reasonable steps" that must be taken when renouncing citizenship to gain exemption from s 44(i). As a result, four more House of Representative members under similar circumstances resigned their seats to re-contest them at by-elections.
The eight senators were replaced by High-Court-ordered countbacks, and were all replaced by candidates from the same tickets at the 2016 election. By-elections were held for the seats of the seven affected House of Representative members; six of the seven re-contested and won their seats, while another was won by a member of the same party.
The crisis prompted calls by some people for constitutional reform to prevent dual citizens from being disqualified, which would require a referendum. An opinion poll taken in late November to early December 2017 found overall opposition to changing s 44(i) of 49% to 47% (within the margin of error), with 5% undecided.
Background.
Legal requirements.
The Australian Constitution does not require candidates for the Commonwealth Parliament to hold Australian citizenship (which did not come into existence until 1949), but this is now required by the "Commonwealth Electoral Act 1918" as amended. Members must not owe allegiance to any other country, including holding a foreign citizenship. Section 44(i) of the Constitution states:
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44. Any person who –
 ;templatestyles src="Block indent/styles.css"/ ;(i.) Is under any acknowledgement of allegiance, obedience, or adherence to a foreign power, or is a subject or a citizen or entitled to the rights or privileges of a subject or citizen of a foreign power
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shall be incapable of being chosen or of sitting as a senator or a member of the House of Representatives.
Earlier challenges and High Court interpretation.
Section 44(i) has generally been interpreted by the High Court of Australia as meaning that persons with dual citizenship are not permitted to stand for election and that a person must take "reasonable steps" to renounce their citizenship of the other country. The section has rarely been invoked before.
In 1990, George Turner, a Sydney-based barrister and independent Senate candidate, threatened High Court action against federal parliamentarians holding dual citizenship. As a result, "The Canberra Times" reported that at least nine MPs elected at the 1987 federal election had renounced foreign citizenships.
In "Sykes v Cleary" (1992), a candidate who had been declared elected in a by-election was found ineligible under Section 44(iv) of the Constitution. The High Court ruled that both of the candidates who were likely to have been elected by a countback were ineligible under s 44(i). When they had become Australian citizens, they had renounced all foreign nationality (as Australian law then required), but they had not attempted to renounce under the law of their home countries and therefore were still subjects of a foreign power. They should have taken at least "reasonable steps" to do that, before nominating. "Reasonable steps" for any future candidate would depend on the individual circumstances. In 1999, in "Sue v Hill", the High Court found that a British citizen who had been declared elected to the Senate in 1998 was disqualified under s 44(i). Although the UK had not been a "foreign power" in 1901, it had been since at least the Australia Act 1986.
Earlier application of section 44 in the 45th Parliament.
The prelude to the crisis began when Bob Day of the Family First Party resigned from the Senate on 1 November 2016 following the collapse of his business. Shortly after Day's resignation, the Senate referred to the High Court the validity of Day's election in July 2016 for a possible breach of section 44(v) of the Constitution. It provides thata person who "has any direct or indirect pecuniary interest in any agreement with the Public Service of the Commonwealth ... shall be incapable of being chosen or of sitting" as a member of Parliament.The basis of the complaint was that Day's Commonwealth-funded electorate office was leasing part of a building in Adelaide which he indirectly owned. The Commonwealth's payments of rent for the office would eventually come into a bank account of his own. In April 2017, the court found that Day was not validly elected at the 2016 election and ordered that a special count of South Australian ballot papers be held to determine his replacement. The court announced that Lucy Gichuhi was elected in his place. The Australian Labor Party lodged a challenge, claiming that Gichuhi might still be a citizen of Kenya, hence ineligible under Constitution section 44(i) as a citizen of a "foreign power". On 19 April 2017 a full court of the High Court found that the objection had not been proven and declared Gichuhi elected.
Senator Rodney Culleton, who had left Pauline Hanson's One Nation on 19 December 2016 to become an independent, had his eligibility to stand in the 2016 election challenged on two constitutional grounds. Among the grounds of ineligibility provided in Section 44, a person cannot sit in either house of the Parliament if they are bankrupt or have been convicted of a criminal offence carrying a potential prison sentence of one year or more. Culleton was declared bankrupt by the Federal Court on 23 December 2016. On 11 January 2017, after receiving an official copy of the judgment, the President of the Senate declared Culleton's seat vacant. Culleton's appeal against that judgment was dismissed by a full court of the Federal Court on 3 February 2017.
This judgment was followed later on the same day by the High Court's decision that Culleton was ineligible owing to conviction for a criminal offence carrying a potential prison sentence of one year or more. This was a decision as the Court of Disputed Returns following a reference by the Senate at the same time as with Day. It was decided that Culleton's possibility of a two-year sentence for larceny that had been in place at the time of the 2016 election rendered him ineligible for election, and that this was not affected by the subsequent annulment of that conviction. The court also held that the resulting vacancy should be filled by a countback of the ballots, in a manner to be determined by a single Justice of the Court. Following that count, on 10 March 2017, the High Court named Peter Georgiou as his replacement, returning One Nation to 4 seats.
Procedure.
The Commonwealth Constitution provides the High Court with original and appellate jurisdiction, and also empowers the Commonwealth parliament to provide additional original jurisdiction. The parliament is also empowered to provide that questions of members' eligibility, of vacancies in either house and that disputed elections shall be determined other than by the relevant house, the position inherited from the Parliament of the United Kingdom. In exercise of these powers, the Commonwealth Electoral Act 1918, which governs federal elections, provides the High Court with a jurisdiction as the federal Court of Disputed Returns.
Petition by individual or AEC.
An appropriately interested person, such as a losing candidate or a person entitled to vote in that constituency, may question the result (the "return of the writ") in a federal election by a petition to the High Court as Court of Disputed Returns, normally within 40 days of the result, or by the Australian Electoral Commission. The High Court may hear the whole case itself or may delegate factual questions for determination by the Federal Court; the High Court itself will determine the validity of a candidate's election or of the whole of that particular election, including issues of constitutional interpretation. The admissible grounds for a petition are generally at the Court's discretion but include corruption and do not extend to administrative errors that have not affected the result. The Court can compel production of documents and attendance of witnesses, and can examine witnesses on oath. However, the Court "must make its decision on a petition as quickly as is reasonable in the circumstances", it is not bound by strict rules of evidence, and all of its decisions "shall be final and conclusive and without appeal, and shall not be questioned in any way" (thus there is no recourse to the High Court in its other capacities or to the Parliament).
A decision of the Court of Disputed Returns may be made by a single judge, but an issue of constitutional interpretation is likely to be made by the Full Court. If the complaint is upheld, the decision and its effect will be one of the following:
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Costs will be as in ordinary proceedings in the High Court. The Commonwealth or any party to an unsuccessful petition may have to pay any or all of the costs.
Parliamentary reference.
In addition, there may be a reference by resolution of either house of the parliament on "[a]ny question respecting the qualifications of a Senator or of a Member of the House of Representatives or respecting a vacancy in either House of the Parliament". 
The reference (commonly termed a referral) is communicated to the Court by, as appropriate, the Speaker of the House of Representatives or the President of the Senate. There is no time limit, but in other respects the procedure is the same as with a petition, although the Court may also allow or request other persons to be heard. The Court is empowered to declare:
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In practice, the references request the Court to determine how a vacancy so arising should be filled. The full Court may order a countback and appoint one member of the Court to supervise the process and confirm the result.
Common informer action.
Section 46 of the Constitution allows any member of the public to sue a member of the Parliament for a penalty of one hundred pounds (a very large sum in 1901) for every day on which they sit while disqualified, until the Parliament otherwise provides. The "Common Informers (Parliamentary Disqualifications) Act" 1975 (Cth) has now provided otherwise, fixing the penalty at a total of $200 for any parliamentarian who has sat while ineligible in the past 12 months and $200 per sitting day after the suit is instituted. It was uncertain whether the procedure could be used without a prior finding of disqualification by the Court of Disputed Returns or the relevant House. The question was the subject of a referral to the Full Court of the High Court in "Alley v Gillespie", heard on 12 December 2017. The Full Court determined that the mechanism could only be invoked after a prior finding of ineligibility by the House of Representatives or the Senate (depending on which house the affected person was a member of), or by the High Court sitting as the Court of Disputed Returns under Part XXII of the "Commonwealth Electoral Act 1918" (Cth) following a petition or referral. On 11 July 2018, Justice Gordon made orders in the High Court for the first time that judgment be entered for a plaintiff against defendants in a Common Informer