|Single transferable vote|
|7 September 2013|
|Next federal election|
Canberra, ACT, Australia
|This article is part of a series on the
politics and government of
The Senate is the upper house of the bicameral Parliament of Australia, the lower house being the House of Representatives. The composition and powers of the Senate are established in Chapter I, Part II of the Australian Constitution. There is a total of 76 senators; 12 senators are elected from each state, regardless of population. Each of the two autonomous internal territories has two senators. Senators are popularly elected under a single transferable vote system of proportional representation. There is no constitutional requirement for the election of senators to take place at the same time as those for members of the House of Representatives, though the government usually tries to synchronise election dates.
Senators normally serve fixed six-year terms, unless the Senate is dissolved earlier in a double dissolution. Following a double dissolution half the state senators serve only three-year terms. The term of the territory senators expires at the same time as there is an election for the House of Representatives.
Unlike upper houses in most parliamentary systems, the Senate is vested with significant power, including the capacity to block legislation initiated by the government in the House of Representatives, making it a distinctive hybrid of British Westminster bicameralism and US-style bicameralism.
In the current Senate, the Liberal/National Coalition government holds 33 seats and the Australian Labor Party opposition has 25 seats. The crossbench of 18 consists of ten Greens seats, three Palmer United Party seats, with one each for the Australian Motoring Enthusiast Party, the Liberal Democrats, the Family First Party, and two independents, Nick Xenophon and John Madigan. The Coalition requires six non-Coalition Senators to pass legislation.
- 1 Origins and role
- 2 Nexus
- 3 Where the houses disagree
- 4 Blocking supply
- 5 Membership
- 6 Procedure
- 7 Composition
- 8 See also
- 9 References
- 10 Further reading
- 11 External links
Origins and role
The Commonwealth of Australia Constitution Act (Imp.) of 1900 established the Senate as part of the new system of dominion government in newly federated Australia. From a comparative governmental perspective, the Australian Senate exhibits distinctive characteristics. Unlike upper houses in other Westminster system governments, the Senate is not a vestigial body with limited legislative power. Rather it was intended to play, and does play an active role in legislation. Rather than being modelled after the House of Lords, as the Canadian Senate was, the Australian Senate was in part modelled after the United States Senate, by giving equal representation to each state. The Constitution intended to give less populous states added voice in a Federal legislature, while also providing for the revising role of an upper house in the Westminster system.
Although the Prime Minister, by convention, serves as a member of the House of Representatives, other ministers may come from either house, and the two houses have almost equal legislative power. As with most upper chambers in bicameral parliaments, the Senate cannot introduce appropriation bills (bills that authorise government expenditure of public revenue) or bills that impose taxation, that role being reserved for the lower house. That degree of equality between the Senate and House of Representatives reflects the desire of the Constitution's authors to address smaller states' desire for strong powers for the Senate as a way of ensuring that the interests of more populous states as represented in the House of Representatives did not totally dominate the government. This situation was also partly due to the age of the Australian constitution – it was enacted before the confrontation in 1909 in Britain between the House of Commons and the House of Lords, which ultimately resulted in the restrictions placed on the powers of the House of Lords by the Parliament Acts 1911 and 1949.
In practice, however, most legislation (except for private member's bills) in the Australian Parliament is initiated by the Government, which has control over the lower house. It is then passed to the Senate, which may amend the bill or refuse to pass it. In the majority of cases, voting takes place along party lines, although there are occasional conscience votes.
The number of members of the House of Representatives has to be "as nearly as practicable" double the number of Senators. The reasons for the nexus are twofold:
- maintain a constant influence for the smaller states.
- maintain a constant balance of the two houses in case of a joint sitting after a double dissolution.
A referendum held in 1967 to eliminate the nexus failed to pass.
Where the houses disagree
If the Senate twice in a three-month period refuses to pass the same piece of legislation that was initiated in the lower house, the government may either abandon the bill or continue to revise it, or, in certain circumstances outlined in section 57 of the Constitution, the Prime Minister can recommend the governor-general dissolve the entire parliament in a double dissolution. In such an event, the entirety of the Senate faces re-election, as does the House of Representatives, rather than only about half the chamber as is normally the case. After a double dissolution election, if the bills in question are reintroduced, and if they again fail to pass the Senate, the governor-general may agree to a joint sitting of the two houses in an attempt to pass the bills. Such a sitting has only occurred once, in 1974.
The double dissolution mechanism is not available for bills that originate in the Senate and are blocked in the lower house.
After a double dissolution election Section 13 of the Constitution requires the Senate to divide the senators into two classes, with the first class having a three-year term, and the second class six. The Senate has determined that this division shall result from the order of election, with those elected first having a six-year term.
On 8 October 2003, the then Prime Minister John Howard initiated public discussion of whether the mechanism for the resolution of deadlocks between the houses should be reformed. High levels of support for the existing mechanism, and a very low level of public interest in that discussion, resulted in the abandonment of these proposals.
The constitutional text denies the Senate the power to originate or amend appropriation bills, in deference to the conventions of the classical Westminster system. Under a traditional Westminster system, the executive government is responsible for its use of public funds to the lower house, which has the power to bring down a government by blocking its access to supply – i.e. revenue appropriated through taxation. The arrangement as expressed in the Australian Constitution, however, still leaves the Senate with the power to reject supply bills or defer their passage – undoubtedly one of the Senate's most contentious and powerful abilities.
The ability to block supply was the origin of the 1975 Australian constitutional crisis. The Opposition used its numbers in the Senate to defer supply bills, refusing to deal with them until an election was called for both Houses of Parliament, an election which it hoped to win. The Prime Minister of the day, Gough Whitlam, contested the legitimacy of the blocking and refused to resign. The crisis brought to a head two Westminster conventions that, under the Australian constitutional system, were in conflict – firstly, that a government may continue to govern for as long as it has the support of the lower house, and secondly, that a government that no longer has access to supply must either resign or be dismissed. The crisis was resolved in November 1975 when Governor-General Sir John Kerr dismissed Whitlam's government and appointed a caretaker government on condition that elections for both houses of parliament be held. This action in itself was a source of controversy and debate continues on the proper usage of the Senate's ability to block supply and on whether such a power should even exist.
Under sections 7 and 8 of the Australian Constitution, the Senate must:
- comprise an equal number of senators from each original state,
- each original state shall have at least six senators, and
- laws governing the election of senators must be non-discriminatory among states.
These conditions have periodically been the source of debate, and within these conditions, the composition and rules of the Senate have varied significantly since federation.
The voting system for senators has changed twice since federation. The original arrangement involved a first-past-the-post block voting or "winner takes all" system, on a state-by-state basis. This was replaced in 1919 by preferential block voting. Block voting tended to produce landslide majorities and even "wipe-outs". For instance, from 1920 to 1923 the Nationalist Party of Australia had 35 of the 36 senators, and from 1947 to 1950, the Australian Labor Party had 33 of the 36 senators.
In 1948, proportional representation on a state-by-state basis became the method for electing senators.
|Senate election – Tasmania|
☐ Family First
|☐ Abetz E
☐ Barnett G
☐ Parry S
|☐ Larner R
☐ Watts A
|☐ Onsman Y
☐ Cass S
|☐ Petrusma J
☐ Bergman L
☐ Smith L
|☐ Mitchell D
☐ Fracalossi M
|☐ Murphy S
☐ Murphy H
|☐ Martin S
☐ Newman J
|☐ Milne C
☐ Cassidy K
☐ Millen T
|☐ O'Brien K
☐ Polley H
☐ Price D
☐ Wells N
|☐ Newitt R
☐ Gargan E
☐ Ottavi D
☐ McDonald J
Electors must either:
- Vote for an individual party by writing the number "1" in a single box above the thick black line (♦♦♦♦) – this means the elector wants their preferences distributed according to a party's or group's officially registered group voting ticket.
- Vote for all candidates by writing the numbers 1, 2, 3, through to the last number (in this example, 26) in all the individual boxes below the line (♦♦♦♦).
Because each state elects six senators at each half-senate election, the quota for election is only one-seventh or 14.3% (one third or 33.3% for territories, where only two senators are elected). Once a candidate has been elected with votes reaching the quota amount, any votes they receive in addition to this may be distributed to other candidates as preferences.
With an odd number of seats in a half-Senate election (3 or 5), 50.1% of the vote wins a majority (2/3) or (3/5).
With an even number of seats in a half-Senate election (6), 57.1% of the vote is needs to win a majority of seats (4/6).
Some states may have over 80 candidates on their ballot papers, and voters must individually number every single candidate for a "below the line" vote to count. As a result the "above the line" system was implemented. About 98% of electors vote "above the line".  Above the line votes are interpreted as if the elector had filled in all the squares below the line, according to a registered ticket(s). There may be up to three registered tickets for each party. Above the line voting greatly speeds up counting which is now done by computer.
The ungrouped candidates in the far right column do not have a box above the line. Therefore they can only get a primary (number 1) vote from electors who vote below the line. For this reason, some independents register as a group, either with other independents or by themselves, such as groups F and G in the above example.
Names of parties can be shown only if the parties are registered, which requires, among other things, a minimum of 500 members.
Order of parties
The order of parties on the ballot papers, and the order of ungrouped candidates is determined by a ballot conducted by the Electoral Commission.
Candidates, parties, and groups pay a deposit which is forfeit if they fail to achieve a certain percentage of the vote.
Candidates, parties, and groups earn a public subsidy if they gain a certain percentage of the vote.
Section 15 of the Constitution provides that a casual vacancy of a State senator shall be filled by the State Parliament. If the previous senator was a member of a particular political party the replacement must come from the same party, but the State Parliament may choose not to fill the vacancy, in which case Section 11 requires the Senate to proceed regardless.
The size of the Senate has changed over the years. The Constitution originally provided for 6 senators for each state, resulting in a total of 36 senators. The Constitution permits the Parliament to increase the number of senators, provided that equal numbers of senators from each original state are maintained. Accordingly, in 1948, Senate representation was increased to 10 senators for each state, increasing the total to 60.
In 1975, the two territories, the Northern Territory and the Australian Capital Territory, were given an entitlement to elect two senators each for the first time, bringing the number to 64. The senators from the Northern Territory also represent constituents from Australia's Indian Ocean Territories (Christmas Island and the Cocos (Keeling) Islands), while the senators from the Australian Capital Territory also represent voters from the Jervis Bay Territory.
The latest expansion in Senate numbers took place in 1984, when the number of senators from each state was increased to 12, resulting in a total of 76 senators.
Normally, elections for senators take place at the same time as those for members of the House of Representatives. However, because their terms do not coincide, the incoming Parliament will for some time comprise a new House of Representatives and an old Senate.
Section 13 of the Constitution requires that in half-Senate elections the election of State senators shall take place within one year before the places become vacant. The actual election date is determined by the Governor of each State, who acts on the advice of the State Premier. The Governors almost always act on the recommendation of the Governor-General, with the last independent Senate election writ being issued by the Governor of Queensland during the Gair Affair in 1974.
Slightly more than half of the Senate is contested at each general election (half of the 72 state senators, and all four of the territory senators), along with the entire House of Representatives. Except in the case of a double dissolution, senators are normally elected for fixed terms of six years, commencing on 1 July following the election, and ceasing on 30 June six years later.
The term of the four senators from the territories is not fixed, but is defined by the dates of the general elections for the House of Representatives, the period between which can vary greatly, to a maximum of three years and three months. Territory senators commence their terms on the day that they are elected. Their terms expire the day prior to the following general election day.
Following a double dissolution, all 76 senators face re-election. If there is an early House election outside the 12-month period in which Senate elections can occur, the synchronisation of the election will be disrupted, and there can be elections at which only half the Senate is up for election. The last time this occurred was on 21 November 1970.
Issues with equal representation
Each state elects the same number of senators, meaning there is equal representation for each of the Australian states, regardless of population, so the Senate, like many upper houses, does not adhere to the principle of "one vote one value". Tasmania, with a population of around 500,000, elects the same number of senators as New South Wales, which has a population of over 7 million. Because of this imbalance, governments favoured by the more populous states are occasionally frustrated by the extra power the smaller states have in the Senate, to the degree that former Prime Minister Paul Keating famously referred to the Senate's members as "unrepresentative swill". The proportional election system within each state ensures that the Senate incorporates more political diversity than the lower house, which is basically a two party body. The elected membership of the Senate more closely reflects the first voting preference of the electorate as a whole than does the composition of the House of Representatives, despite the large discrepancies from state to state in the ratio of voters to senators. This often means that the composition of the Senate is different from that of the House of Representatives, contributing to the Senate's function as a house of review.
While the states are equally represented in the Senate, which was originally regarded as the "State's House", the Senate has no power to amend or initiate "money" bills. Hence representation in the Senate is not quite equal. For the first 10 years of Federation, parties were weak and fluid, but after this time, the "state's house" attribute disappeared, and the Senate became a party's house as well.
With proportional representation, and the small majorities in the Senate compared to the generally larger majorities in the House of Representatives, and the requirement that the number of members of the House be "nearly as practible" twice that of the Senate, a joint sitting after a double dissolution is more likely than not to lead to a victory for the House over the Senate. When the Senate had an odd number of Senators retiring at an election (3 or 5), 51% of the vote would lead to a clear majority of 3 out of 5 per state. With an even number of Senators retiring at an election, it takes 57% of the vote to win 4 out of 6 seats, which may be insurmountable. This gives the House an unintended extra advantage in joint sittings but not in ordinary elections, where the Senate may be too evenly balanced to get House legislation through.
The Government does not need the support of the Senate to stay in office. However, if the governing party doesn't have a majority in the Senate, it can often find its agenda frustrated in the upper house. This can be the case even when the government has a large majority in the House.
The overwhelming majority of senators have always been elected as representatives of political parties. Parties which currently have representation in the Senate are:
- The Coalition – Liberal Party of Australia, Liberal National Party of Queensland, National Party of Australia and Country Liberal Party
- Australian Labor Party
- Australian Greens
- Palmer United Party
- Australian Motoring Enthusiasts Party
- Liberal Democratic Party
- Family First
Other parties that have achieved Senate representation in the past include the Australian Democrats, One Nation, Nuclear Disarmament Party, Liberal Movement, the Democratic Labour Party and the related but separate Democratic Labor Party.
Due to the need to obtain votes state-wide, independent candidates have difficulty getting elected. The exceptions in recent times have been elected in less populous States – the former Tasmanian Senator Brian Harradine and the current South Australian Senator Nick Xenophon.
The Australian Senate serves as a model for some politicians in Canada, particularly in the Western provinces, who wish to reform the Canadian Senate so that it takes a more active legislative role.
There are also small factions in the United Kingdom (both from the right and left) who wish to the see the House of Lords take on a structure similar to that of the Australian Senate.[who?]
The Australian Senate typically sits for 50 to 60 days a year. Most of those days are grouped into 'sitting fortnights' of two four-day weeks. These are in turn arranged in three periods: the autumn sittings, from February to April; the winter sittings, which commence with the delivery of the budget in the House of Representatives on the first sitting day of May and run through to June or July; and the spring sittings, which commence around August and continue until December, and which typically contain the largest number of the year's sitting days.
The senate has a regular schedule that structures its typical working week.
Dealing with legislation
All bills must be passed by a majority in both the House of Representatives and the Senate before they become law. Most bills originate in the House of Representatives, and the great majority are introduced by the government.
The usual procedure is for notice to be given by a government minister the day before the bill is introduced into the Senate. Once introduced the bill goes through several stages of consideration. It is given a first reading, which represents the bill's formal introduction into the chamber.
The first reading is followed by debate on the principle or policy of the bill (the second reading debate). Agreement to the bill in principle is indicated by a second reading, after which the detailed provisions of the bill are considered by one of a number of methods (see below). Bills may also be referred by either House to their specialised standing or select committees. Agreement to the policy and the details is confirmed by a third and final reading. These processes ensure that a bill is systematically considered before being agreed to.
The Senate has detailed rules in its standing orders that govern how a bill is considered at each stage. This process of consideration can vary greatly in the amount of time taken. Consideration of some bills is completed in a single day, while complex or controversial legislation may take months to pass through all stages of Senate scrutiny.
In addition to the work of the main chamber, the Senate also has a large number of committees which deal with matters referred to them by the Senate. These committees also conduct hearings three times a year in which the government's budget and operations are examined. These are known as estimates hearings. Traditionally dominated by scrutiny of government activities by non-government senators, they provide the opportunity for all senators to ask questions of ministers and public officials. This may occasionally include government senators examining activities of independent publicly funded bodies, or pursuing issues arising from previous governments' terms of office. There is however a convention that senators do not have access to the files and records of previous governments when there has been an election resulting in a change in the party in government.
Holding governments to account
One of the functions of the Senate, both directly and through its committees, is to scrutinise government activity. The vigour of this scrutiny has been fuelled for many years by the fact that the party in government has seldom had a majority in the Senate. Whereas in the House of Representatives the government's majority has sometimes limited that chamber's capacity to implement executive scrutiny, the opposition and minor parties have been able to use their Senate numbers as a basis for conducting inquiries into government operations. When the Howard government won control of the Senate in 2005, it sparked a debate about the effectiveness of the Senate in holding the government of the day accountable for its actions. Government members argued that the Senate continued to be a forum of vigorous debate, and its committees continued to be active. The Opposition leader in the Senate suggested that the government had attenuated the scrutinising activities of the Senate. The Australian Democrats, a minor party which has frequently played mediating and negotiating roles in the Senate, expressed concern about a diminished role for the Senate's committees.
Senators are called upon to vote on matters before the Senate. These votes are called divisions in the case of Senate business, or ballots where the vote is to choose a senator to fill an office of the Senate (such as President of the Australian Senate).
Party discipline in Australian politics is extremely tight, so divisions almost always are decided on party lines. Nevertheless, the existence of minor parties holding the balance of power in the Senate has made divisions in that chamber more important and occasionally more dramatic than in the House of Representatives.
When a division is to be held, bells ring throughout the parliament building for four minutes, during which time senators must go to the chamber. At the end of that period the doors are locked and a vote is taken, by identifying and counting senators according to the side of the chamber on which they sit (ayes to the right of the chair, noes to the left). The whole procedure takes around eight minutes. Senators with commitments that keep them from the chamber may make arrangements in advance to be 'paired' with a senator of the opposite political party, so that their absence does not affect the outcome of the vote.
The senate contains an even number of senators, so a tied vote is a real prospect (which regularly occurs when the party numbers in the chamber are finely balanced). Section 23 of the Constitution requires that in the event of a tied division, the question is resolved in the negative. The system is however different for ballots for offices such as the President. If such a ballot is tied, the Clerk of the Senate decides the outcome by the drawing of lots. In reality, conventions govern most ballots, so this situation does not arise.
Political parties and voting outcomes
The extent to which party discipline determines the outcome of parliamentary votes is highlighted by the rarity with which members of the same political party will find themselves on opposing sides of a vote. The exceptions are where a conscience vote is allowed by one or more of the political parties; and occasions where a member of a political party crosses the floor of the chamber to vote against the instructions of their party whip. Crossing the floor very rarely occurs, but is more likely in the Senate than in the House of Representatives.
One feature of the government having a majority in both chambers between 1 July 2005 and the 2007 elections was the potential for an increased emphasis on internal differences between members of the government parties. This period saw the first instances of crossing the floor by senators since the conservative government took office in 1996: Gary Humphries on civil unions in the Australian Capital Territory, and Barnaby Joyce on voluntary student unionism. A more significant potential instance of floor crossing was averted when the government withdrew its Migration Amendment (Designated Unauthorised Arrivals) Bill, of which several government senators had been critical, and which would have been defeated had it proceeded to the vote. The controversy that surrounded these examples demonstrated both the importance of backbenchers in party policy deliberations and the limitations to their power to influence outcomes in the Senate chamber.
|Party||Votes||%||Swing||Seats won||Total seats||Change|
|Australian Labor Party||4,038,591||30.11||–5.02||12||25||–6|
|Palmer United Party||658,976||4.91||+4.91||3 (2)||3 (2)||+3 (+2)|
|Liberal Democratic Party||523,831||3.91||+2.10||1||1||+1|
|Family First Party||149,306||1.11||–0.99||1||1||+1|
|Democratic Labour Party||112,549||0.84||–0.22||0||1||0|
|Australian Motoring Enthusiast Party||67,560||0.50||+0.50||1||1||+1|
|Australian Sports Party||2,997||0.02||+0.02||0 (1)||0 (1)||0 (+1)|
Vote tallies and seat counts in parentheses above are for the original Senate election. However, most Senate votes cast in Western Australia were subject to a formal recount. After the final recount the result was duly declared which changed the last two predicted WA Senate spots from Palmer and Labor back to Sports and Green. On 15 November, the AEC successfully petitioned the High Court, acting as the Court of Disputed Returns, to seek an order from the court that the WA Senate election of all six senators (3 Liberal, 1 Labor, 1 Green, 1 Sport) be declared void. On 28 February 2014 it was announced that the half-Senate election in Western Australia would take place on 5 April, which returned 3 Liberal, 1 Labor, 1 Green, 1 Palmer.
The Senate has included representatives from a range of political parties, including several parties that have seldom or never had representation in the House of Representatives, but which have consistently secured a small but significant level of electoral support, as the table shows.
|1901–1903||36||8||28 (11 Prot, 17 FT)|
|1903–1906||36||14||22 (Trenwith, 8 Prot, 12 FT, 1 RTP)|
|1906–1910||36||15||21 (Trenwith, 6 Prot, 14 AS)|
|1962–1965||60||28||30||2 (Turnbull, 1 DLP)|
|1965–1968||60||27||30||3 (Turnbull, 2 DLP)|
|1968–1971||60||27||28||5 (Turnbull, 5 DLP)|
|1971–1974||60||26||26||8 (Townley, Negus, Turnbull, 5 DLP)|
|1974–1975||60||29||29||2 (Townley, 1 LM)|
|1975–1978||64||27||35||2 (Harradine, 1 LM)|
|1985–1987||76||34||33||7||2 (Harradine, 1 NDP)|
|1987–1990||76||32||34||7||3 (Harradine, Vallentine, 1 NDP)|
|1996–1999||76||28||37||7||2||2 (Harradine, Colston )|
|1999–2002||76||29||35||9||1||2 (Harradine, 1 One Nation)|
|2002–2005||76||29||35||8||2||2 (Harradine, 1 One Nation)|
|2005–2008||76||28||39||4||4||1 (Family First)|
|2008–2011||76||32||37||5||2 (Xenophon, 1 Family First)|
|2011–2014||76||31||34||9||2 (Xenophon, 1 DLP)|
|2014–2017||76||25||33||10||8 (3 PUP, 1 AMEP, Xenophon, 1 Liberal Democratic Party, 1 Family First, 1 DLP)|
- President of the Australian Senate
- Double dissolution
- Women in the Australian Senate
- Clerk of the Australian Senate
- Members of the Parliament of Australia who have served for at least 30 years
- Father of the Australian Senate
- List of Australian Senate appointments
- Canberra Press Gallery
- Consultative Group on Constitutional Change (March 2004). "Resolving Deadlocks: The Public Response". p. 8.
- "Chapter 4, Odgers' Australian Senate Practice". Aph.gov.au. 2 February 2010. Retrieved 2010-07-17.
- Victorian Electoral Boundaries Commission (6 October 2005). "VEC Media Release: Electoral Boundaries Commission releases State upper house boundaries". Retrieved 2013-08-19.
- Australian Electoral Commission (20 December 2007). "Media Release 2007: Successful Senate candidates elected in Victoria". Retrieved 2013-08-19.
- Senate (Representation of Territories) Act 1973. No. 39, 1974
- Department of the Senate, Senate Brief No. 1, 'Electing Australia's Senators'. Retrieved August 2007.
- Section 6 of the Senate (Representation of Territories) Act 1973. Retrieved August 2010.
- Question without Notice: Loan Council Arrangements House Hansard,
- Lijphart A., 'Australian Democracy: Modifying Majoritarianism?', Australian Journal of Political Science, Vol. 34, No. 3, 1999, pp 313–326
- Sawer, M., 'Overview: Institutional Design and the Role of the Senate', in Marian Sawer and Sarah Miskin (eds), Representation and Institutional Change: 50 Years of Proportional Representation in the Senate, Papers on Parliament series, Vol. 34, 1999, pp 1–12
- Ted Morton, 'Senate Envy: Why Western Canada Wants What Australia Has', Senate Envy and Other Lectures in the Senate Occasional Lecture Series, 2001–2002, Department of the Senate, Canberra.
- Figures are available for each year on the Senate StatsNet http://www.aph.gov.au/Senate/work/statistics/index.htm
- Department of the Senate website, Senate weekly routine of business http://www.aph.gov.au/Senate/work/routineofbus.htm
- Australian Senate, 'The Senate and Legislation', Senate Brief, No. 8, 2008, Department of the Senate, Canberra.
- Australian Senate, 'Consideration of legislation', Brief Guides to Senate Procedure, No. 9, Department of the Senate, Canberra.
- Senator the Hon Nick Minchin media release, 30 June 2006 http://www.financeminister.gov.au/media/2006/mr_432006.html
- Senator Chris Evans, The tyranny of the majority (speech), 10 November 2005 http://www.chrisevans.alp.org.au/news/1105/senatespeeches10-01.php
- Australian Democrats media release, 4 July 2006 http://www.democrats.org.au/docs/2006/PR_Senate_Attack_Accountability.pdf
- Senate Standing Orders, numbers 7, 10, 98–105, 163
- Deirdre McKeown, Rob Lundie and Greg Baker, 'Crossing the floor in the Federal Parliament 1950 – August 2004', Research Note, No. 11, 2005–06, Department of Parliamentary Services, Canberra.
- John Uhr, 'How Democratic is Parliament? A case study in auditing the performance of Parliaments', Democratic Audit of Australia, Discussion Paper, June 2005. Retrieved January 2008.
- Peter Veness, 'Crossing floor 'courageous, futile', news.com.au, 15 June 2006. Retrieved January 2008.
- Neither of these instances resulted in the defeat of a government proposal, as in both cases Senator Steve Fielding voted with the government.
- Prime Minister's press conference, 14 August 2006 http://www.pm.gov.au/news/interviews/Interview2073.html
- "Nationals won't toe Libs' line: Joyce – SMH 18/9/2008". News.smh.com.au. 18 September 2008. Retrieved 2010-07-17.
- "First Preferences by Group". Virtual Tally Room: 2013 election. AEC. 1 November 2013. Retrieved 13 November 2013.
- "Senate Results: Summary". ABC. 2013. Retrieved 13 November 2013.
- The table has been simplified in the following ways:
- Stanley Bach, Platypus and Parliament: The Australian Senate in Theory and Practice, Department of the Senate, 2003.
- Harry Evans, Odgers' Australian Senate Practice, A detailed reference work on all aspects of the Senate's powers, procedures and practices.
- John Halligan, Robin Miller and John Power, Parliament in the Twenty-first Century: Institutional Reform and Emerging Roles, Melbourne University Publishing, 2007.
- Wilfried Swenden, Federalism and Second Chambers: Regional Representation in Parliamentary Federations: the Australian Senate and German Bundesrat Compared, P.I.E. Peter Lang, 2004.
- John Uhr, The Senate and Proportional Representation: Public policy justifications of minority representation, Working Paper no. 69, Graduate Program in Public Policy, Australian National University, 1999.