26 April 2023

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Dr Damon Muller
Politics and Public Administration

 

The Terms of Reference for the Joint Standing Committee on Electoral Matters’ inquiry into the 2022 federal election includes:

(g) proportional representation of the states and territories in the Parliament, in the context of the democratic principle of 'one vote, one value'.

The primary way in which the representation of the states and territories in the parliament can be changed is through increasing the size of the Parliament. It is within the powers of the Parliament to increase the size of the parliament but doing so is not without complications. The topic of increasing the size of the parliament has recently attracted media attention.

The process of changing the size of the Parliament

The Australian Constitution provides that the Commonwealth Parliament can determine the size of the Parliament, subject to a number of restrictions.

The size of the Parliament is determined through what is known as the ‘nexus provision’, in section 24 of the Constitution. This provides that the number of members of the House of Representatives must be ‘as nearly as practicable, twice the number of the senators’, and that the number of members in each state should be proportional to the population of the state. That section also requires that no original state shall have fewer than 5 members.

Section 7 of the Constitution provides that the Parliament can determine the number of senators, but that ‘equal representation of the several Original States shall be maintained and that no Original State shall have less than six senators’.

In effect then, to increase the size of Parliament the Parliament must exercise its powers under the Constitution and pass legislation to increase the number of senators for each of the states. This then leads to a change in the number of members of the House of Representatives through a process described in the next section.

The size of the Parliament has been changed by increasing the size of the state representation in the Senate, from the original six senators per state, twice since Federation:[1]

• In 1949 the number of senators per state was increased from the original 6 to 10, following the passage of the Representation Act 1948, increasing the size of the Parliament from 74 to 121.
• In 1984 the number of senators per state was increased from 10 to the current 12, following the passage of the Representation Act 1983, leading to its current size of 151.
• The size of the Parliament has not changed substantially since 1984, despite Australia’s population growing from around 16 million to over 26 million in that time.

The size of the Senate and the House

The size increase of the House is not required to be exact (it is to be ‘as nearly as practicable’) because the number of senators is used in an equation to determine how many seats each state is entitled to (see the Library’s paper on redistributions) and section 24 of the Constitution provides each original state a minimum of 5 seats. With the current 12 senators per state, the House would ideally currently have 148 seats (once you factor in the minimum of five seats for Tasmania and a minimum of one senator per territory, as required under the Commonwealth Electoral Act 1918), though the total has varied between 148 and the current 151, including 4 territory seats.

The Constitution does not require that each state have an even number of senators, however when it has been changed in the past it has been by even numbers. For simplicity this Quick Guide will assume that any subsequent change will also increase the senators of each state by an even number (to maintain equal numbers of senators to be elected at each half-Senate election), of 2 senators per state.

If the Parliament was to increase the number of senators per state by 2 (2 for each of the 6 states, times 2), roughly 24 new members will be added to the House of Representatives. On the basis of the current population numbers, having each state elect 14 senators (an increase of 2 per state), the House of Representatives would have 174 members, an increase of 23 (see Table 1 of the Appendix).

Territory representation

The senators for the territories are not included under the above provisions; section 122 of the Constitution provides that the Parliament can determine the representation of the territories in each of the Houses. The Parliament can change the number of senators the territory is entitled to, by legislation, without otherwise affecting the size of the Parliament. The number of senators for each of the territories is provided for by the Commonwealth Electoral Act 1918 and is not affected by the Representation Acts.

The number of state senators does not affect the number of territory senators, but does affect the number of members each territory is entitled to (because the entitlement of the territories to members is based on the same calculation as the states). And while within each state and territory each electorate has to have about the same number of electors, the number of electorates each state and territory is entitled to is determined by their whole population, relative to the Australian population.

The consequences of changing the size of the Parliament

There are electoral, representational and practical consequences to changing the size of the Parliament.

Elections

Any proposed Representation Act must provide for how the increase in the size of the Senate should be effected by a single election, as required under section 14 of the Constitution. While the exact details are a matter for the Parliament of the day, the precedent of the 2 prior increases suggests that if each state was granted 2 more senators the next Senate election would elect 8 senators per state, one of which would be given a short term (likely the last senator elected for each state). Subsequent half-Senate elections would elect 7 senators per state, each for a 6-year term.

Changing the number of senators elected will likely change the electoral dynamics of the Senate election. The quota for election at a Senate election is based on one more than the number of senators to be elected, divided by the number of votes. The more senators that are up for election, the lower the vote they need to achieve a quota.

Any increase would trigger a redistribution of electorates in every state except Tasmania (which, due to its small population would not gain a seat but as an original state retain its constitutional minimum of five House of Representatives seats, unless the increase in the size of the Senate was particularly large, as discussed below). Each of these state redistributions would have to be completed prior to the next House of Representatives election. Such a large change would leave very few federal electoral boundaries unaltered.

Representation

As the population of Australia has increased the number of electors represented by each member and senator has also increased, and the periodic changes to the size of the parliament have not kept pace:

• At Federation the average number of electors represented by each member was around 12,000.
• In 1949 the average was around 40,000 electors per seat
• In 1984 it was around 67,000 electors per seat.

Under a minimally expanded parliament, each of the 174 seats would represent around 103,000 electors, compared to the current average of around 119,000 (as of December 2022) electors per division (see Table 2 in the Appendix for details).

Practical

The Chamber of the House of Representatives is designed to seat up to 172 members, so with 174 members seating might be cosy without modifications (total capacity 240 members). Any further expansion of the Parliament might lead to a situation such as the British House of Commons, which can physically accommodate a maximum of 427 of the 650 members.

Each Member and Senator has an office suite in Parliament House. With 151 Members and 76 Senators, the building is essentially at capacity. Relatively major changes would need to be made to the building to accommodate additional members and senators.

While the specifics of these possible physical changes to Parliament House are outside the scope of this Quick Guide, possible changes might involve moving some services out of the building, such as the corporate functions of the Parliamentary Departments, the Parliamentary Library, and the Press Gallery.[2] Members and Senators cannot realistically be accommodated outside Parliament House as they must be able to reach the respective Chamber within around 4 minutes when a division is called (though this is defined under the Standing Orders, and could be changed). Any substantial changes to the building will require accommodation of heritage and design integrity considerations.

Also outside the scope of this Quick Guide, but worth noting, is the effect of the size of the Parliament on the ability of the Parliament to undertake its functions. Increasing the size of the chambers will impact speaking opportunities in the chambers and lead to more parliamentarians being available to participate in committee activity. It might also lead to reconsidering the size of the ministry, which is currently limited by legislation to 30 members, with an additional 12 Parliamentary Secretaries or Assistant Ministers.

Proportionality and the size of the Parliament

An additional concern is the difference in the ratio of parliamentarians to electors (or residents more generally) and how it differs between states and territories, plus between the Chambers of Parliament. In general, a small change in the number of Senators will effectively not fix the discrepancies between the states.

In the case of the Senate, this is largely an unsolvable problem. Each of the original states has a constitutional guarantee to the same number of senators, whether its population is 8.1 million (NSW) or 571,000 (Tasmania). Increasing the size of the Senate is never going to meaningfully close this gap.

For the House of Representatives, the situation is more complex, but again driven mostly by the smaller populated state of Tasmania and the territories. Using the 2022 population numbers Tasmania would not become entitled to its 5 House seats on the basis of population until each state has 18 senators (meaning the House will have 224 Members). Under this scenario each state and territory will have around 80,000 electors per member (see Table 2 in the Appendix for the calculations). Until that point, however, Tasmania and the NT will be well under the average national enrolment and the ACT will generally be over the average.

Conclusion

It is not difficult to argue that the size of the Parliament has failed to keep up with both increases in the size of the population and increases in the complexity of governing. The process of increasing the size of the Parliament is legislatively straightforward and has successfully been done twice in the past, though the most recent time was so long ago there are likely to be few people still in politics who remember it. The political and practical consequences are significant, however, and also slightly difficult to predict. It is likely that, should the JSCEM recommend the Parliament again be extended, the resulting debate will no doubt be robust.

 

Appendix

Using the formula provided for in section 65 of the Electoral Act it is possible to project the likely size of the House of Representatives based on the increased Senate size. The ABS population estimates from September 2022 (the most recent at the time of publication) were applied to determine the seat entitlement for each state.

Table 1: Number of Members of the House of Representatives per state and territory based on number of senators

	Number of Members
Senators per state	NSW	Vic	QLD	SA	WA	Tas	NT	ACT	Total size of the House
12	46	38	30	10	16	5	2	3	150
14	54	44	35	12	19	5	2	3	174
16	62	50	40	14	21	5	2	3	197
18	70	57	46	16	24	5	2	4	224

On the basis of the calculated numbers of divisions, using the AEC estimates of eligible electors for each state and territory, gives the following average enrolments under the new House and Senate sizes.[3]

Table 2: Average number of electors per electorate in each state and territory based on the number of senators

		Average number of electors per electorate
Senators per state	Total Electorates	NSW	Vic	QLD	SA	WA	Tas	NT	ACT	National average
12	150	121,690	118,045	123,238	131,046	118,131	83,273	83,011	107,013	119,231
14	174	103,662	101,948	105,633	109,205	99,479	83,273	83,011	107,013	102,785
16	197	90,286	89,714	92,429	93,604	90,005	83,273	83,011	107,013	90,785
18	224	79,968	78,697	80,373	81,904	78,754	83,273	83,011	80,260	79,842
Electors		5,597,733	4,485,719	3,697,150	1,310,461	1,890,096	416,366	166,022	321,039	17,884,586

 

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[1].   In 1974 the Parliament legislated to give each of the territories two senators, whose terms were matched to the terms of members of the House of Representatives.

[2].   Some of the staff of the Department of Parliamentary Services are already located elsewhere in Canberra.

[3].   Estimates of electors is used rather than total enrolments to put an upper limit on the numbers; redistributions are based on actual enrolments, but enrolment rates can change over time.

 

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