Research Note 19 1998-99

An Electoral Threshold for the Senate?

Margaret Healy
Politics and Public Administration Group

Gerard Newman
Statistics Group
30 March 1999

Introduction

An electoral threshold is the requirement for a party or candidate to receive a minimum proportion of the vote in order to gain representation. The creation of an electoral threshold for the Senate has gained recent publicity as a result of a proposal put forward previously by Liberal MPs Tony Abbott and Wilson Tuckey and most recently by New South Wales Liberal Party Senator Helen Coonan.

A frequently expressed concern is that the ability to govern effectively in Australia is impaired by the lack of a government majority in the Senate. In these circumstances the Senate is likely to use its constitutional powers to reject or amend legislation. As it would require constitutional amendment to change the powers of the Senate, and because referendum proposals have rarely succeeded in Australia, attention has instead been given to some modification of the electoral system. The adoption of a threshold is a minimalist solution which would not in itself prevent the election of minor parties and independents but which would increase the relative importance of the primary vote against the distribution of preferences. It maintains the ability of a voter to choose the candidate and to rank that candidate against others from the same party.

Electoral systems have a number of functions which need to be held in balance for the effective operation of the democratic process. An electoral system needs to be representative of geographic regions, political beliefs and the societal and cultural aspects of the population. The system must be fair and must not discriminate in favour of one group against another, and should enable voters to feel that their votes can make a difference. Similarly a system should not result in a large wastage of votes, as occurred under the first-past-the-post and the preferential voting systems used for Senate elections until 1949. Both majorities and minorities should be fairly represented. It is essential that minorities are not able to thwart the will of the majority, as this would be a negation of democratic principles. Other functions of and criteria for an electoral system include the promotion of stable government, the facilitation of viable and effective opposition, that seats won should as far as possible be in proportion to votes received, and that power exercised should bear some relationship to the vote received.

Not all these criteria for an electoral system are reconcilable, and no system will work perfectly. Nonetheless, if it is believed firstly that by and large the Australian electoral system is basically fair, effective and acceptable to the voters, and secondly that proportional representation reconciles conflicts between the institutional design of the Senate and democratic representation, then the important question is whether any adaptation of the system can preserve the benefits while alleviating problems.

The Senate electoral system and the quota

The Senate voting system is a proportional preferential system. In order to be elected a candidate must gain a quota of votes. This is determined by dividing the total number of formal votes in the count by one more than the number of senators to be elected, and adding one to the result. As there are 12 senators from each state, at a half Senate election the number of senators to be elected is six, and the quota is 14.29 per cent of the vote. At a double dissolution, when all 12 positions must be filled, the quota is 7.69 per cent. Once a candidate gains a quota of votes, any surplus votes are transferred to the next preference expressed on the ballot paper, and so on until no further quotas can be filled by the downwards distribution of surplus votes. Any remaining quota is filled by progressive exclusion of candidates, starting with the candidate with fewest votes and working upwards. The second preferences are distributed until the next candidate is excluded, and so on until a candidate reaches a quota.

How would a threshold work?

Under a threshold, candidates receiving fewer than the required number of votes would be excluded from the distribution of preferences, and thus could not be elected. However their preferences could still be distributed. If a threshold is acceptable in principle, the major question then becomes the level of the threshold. Calculations below show the effect of various thresholds on recent Senate elections. Suggestions have been made that the threshold might be 50 per cent of a quota, or 80 per cent, or some percentage of the vote, e.g. five per cent or ten per cent.

Because the quota for a double dissolution is half that required for a half Senate election, it is arguable that a threshold set as a percentage of the primary vote is preferable to a threshold of a percentage of the quota.

A common threshold is five per cent of the primary vote. This is used in Germany and New Zealand and in Armenia, Croatia, the Czech Republic, Georgia, Latvia, Lithuania, Mozambique, Poland, the Republic of Korea, the Russian Federation, and Slovakia. Lower thresholds are used in The Netherlands, Israel, Italy, Argentina and Sweden. Some countries require a larger threshold, seven or eight per cent, for parties in coalition, with the threshold rising according to the number of parties in the coalition, so that small parties cannot evade the threshold requirement by notional coalitions. These notional coalition arrangements are known as apparentement.

Because there are only six positions to be filled in each state at the normal half Senate election, it is not possible for a threshold to affect many vacancies. Generally the last position is the one to be determined by the upwards allocation of preferences. If a threshold of half the quota were imposed the required percentage of the primary vote would be only 3.846 at a double dissolution and 7.143 at a half Senate election. At the 1998 election at which six minor party candidates were elected, including Senator Harradine, all except the Democrat from WA (Brian Greig) would have been elected with 50 per cent of the quota. If the threshold was 80 per cent of the quota the only minor party candidates who would have been elected are the One Nation candidate in Queensland (Heather Hill) and the Democrat in South Australia (Meg Lees).

For the proposal to be remotely acceptable to minor parties, the threshold should not make it virtually impossible to be elected, and coalition arrangements, or joint tickets would have to be allowed. An obvious possibility is a Democrat/Green coalition, but others are possible.

The table shows the fate of minor party candidates under thresholds of 50 and 80 per cent of the quota and five and ten per cent of the vote at the Senate elections of 1993, 1996 and 1998.

Fate of Minor Party Senators Under Various Thresholds
Senator	Primary Votes %	Threshold				Likely winner if 80.0% of Quota Threshold applied
		5.0% of Vote (35% of Quota)	50.0% of Quota (7.14% of Vote)	10.0% of Vote (70% of Quota)	80.0% of Quota (11.43% of Vote)
1998 Election
Ridgeway (AD NSW)	7.35	3	3	7	7	ALP/LP(a)
Woodley (AD Qld)	7.81	3	3	7	7	LP
Hill (PHON Qld)	14.83	3	3	3	3
Lees (AD SA)	12.42	3	3	3	3
Greig (AD WA)	6.40	3	7	7	7	ALP
Harradine (HAR Tas)	7.87	3	3	7	7	LP
1996 Election
Bourne (AD NSW)	9.55	3	3	7	7	ALP
Allison (AD Vic)	10.87	3	3	3	7	ALP
Kernot (AD Qld)	13.21	3	3	3	3
Stott-Despoja (AD SA)	14.54	3	3	3	3
Murray (AD WA)	9.35	3	3	7	7	ALP
Brown (GRN Tas)	8.68	3	3	7	7	ALP
1993 Election
Woodley (AD Qld)	7.05	3	7	7	7	ALP
Lees (AD SA)	9.87	3	3	7	7	ALP
Margetts (GRN WA)	5.51	3	7	7	7	ALP
Harradine (HAR Tas)	10.43	3	3	3	7	LP
(a) Result unclear.

The imposition of a Senate threshold is unlikely to give the government of the day a majority in the Senate. Since the expansion of the Parliament in 1984 the most likely outcome of a half Senate election, in each State, is three Senators each from the major parties or five Senators from the major parties (three from one and two from the other) and one minor party Senator. If the minor party Senator were not elected because of a threshold then the most likely outcome would be three Senators from each of the major parties. Thus the most seats that a major party can hope for, except in unusual circumstances, at a half Senate election is 18 from the States and two from the Territories, giving 38 Senators in all.

If a threshold of 80 per cent of the quota had applied at the 1996 and 1998 Senate elections then the composition of the Senate from 1 July 1999 would most likely be 38 Coalition, 34 ALP, 3 Democrats and 1 One Nation - with the minor parties still holding the balance of power. This being so, the treatment of government legislation would depend, as now, on the nature of the minor parties elected.

1. For a more comprehensive discussion on this issue of electoral reform see the forthcoming Current Issue Brief, Should the Australian Electoral System Be Changed? by Scott Bennett.

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