(Almost) everything you need to know about double dissolution elections

Parliament House in Canberra

Following the Senate’s rejection of the Building and Construction Industry bills on 18 April 2016, the Prime Minister announced on 19 April that he intended to advise the Governor-General to dissolve both houses of Parliament under powers provided by section 57 of the Australian Constitution, thus precipitating the first double dissolution election in 29 years (the last double dissolution election was in July 1987). The Prime Minister said that he expects the election to be held on 2 July 2016.

What are the conditions in which a double dissolution can occur?

When the Constitution was written, the authors realised that there needed to be a way to resolve disagreements between the House of Representatives and the Senate over legislation. The solution was provided in section 57 of the Constitution.

Section 57 applies when legislation is passed by the House of Representatives but is rejected by the Senate, or the Senate fails to pass it, or the Senate passes the legislation with amendments that are unacceptable to the House of Representatives. If after three months or more the same situation with the proposed legislation arises again, the legislation becomes a trigger for a double dissolution of the entire Parliament. A list of legislation that fulfils the section 57 requirements is available from the Senate website. These bills are commonly referred to as ‘double dissolution triggers’.

When the requirements of section 57 are fulfilled, the Governor-General may dissolve both houses of Parliament (hence a ‘double dissolution’), leading to a double dissolution election. In practice the Governor-General exercises the power to dissolve the Parliament on the advice of the Prime Minister.

What is a double dissolution election?

In a normal general election all 150 seats of the House of Representatives are up for election, along with 40 of the of the 76 seats in the Senate (half of the 12 seats in each state and all four Senators for the territories). Senators are elected for six-year terms, and half of the Senators are elected every three years.

In an election following a double dissolution, however, all 76 Senate seats are declared vacant. There is essentially no difference for the election of the members of the House of Representatives.

Could we have a normal election now?

The earliest date for a normal half-Senate and House of Representatives election is 6 August 2016.

What are the timing considerations for a double dissolution election?

Under section 57 a double dissolution cannot occur within six months of the date of the expiry of the term of the House of Representatives by the ‘effluxion of time’. Under section 28 of the Constitution, the duration of the House of Representatives in each Parliament is limited to three years from its first meeting.

As the last possible date of the dissolution of the House of Representatives by effluxion of time is 11 November 2016, a double dissolution cannot take place any later than 11 May (six months before November 11).

When have we had double dissolution elections?

There have been six double dissolution elections: in 1914, 1951, 1974, 1975, 1983 and 1987. Odgers’ Australian Senate Practice (chapter 21) provides further information on the causes of each of these.

The outcomes of these elections have been neatly divided between governments being returned to office (1951, 1974 and 1987) and being defeated (1914, 1975 and 1983). The 1951 double dissolution election was the only such election where the government was returned with a majority in the Senate.

How is the election of senators different in a double dissolution election?

To be elected to the Senate, candidates are required to achieve a ‘quota’ of votes, either as first preferences or as later preferences from other candidates. The quota is calculated based on the number of vacancies to be filled.

In a normal half-Senate election the quota is 1/7 of the total formal vote, whereas in a double dissolution election the quota is 1/13 of the total formal vote, because of the greater number of vacancies to be filled. Thus the threshold for being elected in terms of votes received is much lower in a double dissolution election than in a normal half-Senate election.

As detailed in a previous FlagPost, following a double dissolution election section 13 of the Constitution requires the new Senate to divide senators for each state into two classes: those having three-year terms, and those having six-year terms. Historically, the Senate has used the order in which the senators are elected to determine terms, with the first six Senators elected for each state receiving six-year terms.

Section 282 of the Commonwealth Electoral Act 1918 provides an alternative mechanism involving a recount using a normal half-Senate election quota to determine which senators receive six-year terms, but this has not been employed by the Senate since its insertion into the Act in 1984.

When do the new senators’ terms begin?

Under section 13 of the Constitution Senators’ terms commence on the first day of July following their election.

In a normal half-Senate election, senators are elected well before their term begins (the senators elected at the September 2013 federal election, for example, did not take their seats until 1 July 2014). However, under section 13, following a dissolution of the Senate and the subsequent election, the terms of the elected senators are backdated to commence on the previous 1 July.

This means that a double dissolution election held prior to July 2016 would see the terms of the elected senators backdated to commence on 1 July 2015. This would mean in turn that the terms of the three-year senators would expire on 30 June 2018 (only two years after they were elected), thereby requiring an election for those senators well before then. The effect of this would either be a short parliamentary term leading to a normal general election, or a separate half-Senate election followed by a later House of Representatives election.

When does a double dissolution result in a joint sitting?

Under section 57 of the Constitution, if following a double dissolution (and the associated election) the ‘triggering’ legislation is again passed by the House of Representatives but again fails to get through the Senate (or is passed by the Senate with amendments unacceptable to the House), the Governor-General may convene a joint sitting of both Houses. In a joint sitting, the House of Representatives and the Senate vote on the legislation as one body.

A joint sitting is not mandatory. The only joint sitting to date was that which followed the 1974 double dissolution election (the legislation considered at the joint sitting was passed by the Parliament).

What happens at a joint sitting?

Under section 57 the legislation considered at a joint sitting needs to be the ‘proposed law as last proposed by the House of Representatives’ along with any amendments made by one House and not agreed to by the other. The legislation will be passed if agreed to by an absolute majority (currently 114 votes or more) of the joint sitting.

As section 24 of the Constitution requires there be ‘as nearly as practicable’ twice as many members of the House of Representatives as there are Senators, a government with a majority in the House of Representatives is arguably more likely to get its legislation passed in a joint sitting. 


Flagpost is a blog on current issues of interest to members of the Australian Parliament

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