For the first time in nearly three decades the voters of Australia may be going to the polls in a double dissolution election, an election at which the entire memberships of both the Senate and the House of Representatives are contested.
The last, and only the sixth, occasion when voters were so drawn to the polls was on July 11, 1987. The Australia Card legislation was the sole bill relied upon by the Hawke government to call that election.
It gave it an opportunity to have a slightly early election for the House without its being particularly apparent, after a May economic statement, and also seek what had become, for both sides of politics, an elusive majority in the Senate.
The Labor government improved its position in the House but still lacked a majority in the Senate. It had sufficient numbers to secure passage of the Australia Card legislation at a joint sitting.
The party situation in the Senate, however, meant that the card's opponents had the numbers to prevent activation of the scheme by disallowing regulations needed for it to be effective.
As there was much opposition to the Australia Card, not least within the Labor caucus itself, the government, with relief, abandoned it.
The 1987 episode illustrated the great truth about the double dissolution provision in the Constitution (section 57). While it is formulated in terms of legislation in dispute between the Senate and the House, the invariable motivation for its activation has been the quest by governments to secure a majority in the Senate.
Section 57 was, when the Constitution was framed, a unique provision. No other constitution at the time, written or unwritten, made provision for resolution of inter-house disputes in bicameral parliaments.
The new Parliament of Australia was also unique in that both houses were elected on the same adult franchise. The Senate's elective character gave it a formidable legitimacy in comparison to other second chambers such as Britain's hereditary House of Lords and Canada's appointed Senate.
Involvement of electors in resolution of inter-house disputes was a conspicuously democratic feature of the Constitution; another was their involvement in formal amendment of the Constitution (section 128).
Double dissolutions must be based on legislation commencing in the House of Representatives; the High Court ruled in 1974 that a double dissolution could be based on more than one bill.
If the Senate twice, with an interval of at least three months, rejects legislation, unacceptably amends it, or otherwise fails to pass it, the government then has the option of calling a double dissolution.
Such dissolutions cannot occur within six months of "the expiry of the House of Representatives by the effluxion of time".
If the dispute remains unresolved after the elections, the legislation can be submitted to a joint sitting of the two houses. This has only occurred once, in 1974.
The first double dissolution was in 1914. The Cook Liberal government had a bare majority in the House and was down, 29-7, in the Senate.
Joseph Cook immediately set out to resolve the situation with some anti-union preference legislation he knew Labor would contest. The Governor-General, Sir Ronald Munro-Ferguson, newly-arrived, unfamiliar with the Australian Constitution, interpreted the situation in British terms, with a measure of support from the Chief Justice, Sir Samuel Griffith.
Cook resisted, fought for the Constitution, and got his election.
But he did not win it. Labor was back with majorities in both houses.
Fifteen years later a newly-elected Labor government under James Scullin found itself with a big majority in the House but with only seven in the 36-seat Senate. Scullin was no Joseph Cook. Labor, exhausted from two elections in consecutive years, and in constant conflict with the Senate, shied away from a double dissolution, seeking only to achieve a few of its ends by regulation.
In 1949 Robert Menzies knew that the Coalition parties, if they won the December election, would face a similar problem as a consequence of introduction of proportional voting for the Senate.
And so it was. While the new Coalition government had a comfortable majority in the House, the defeated Labor Party had a 34-26 advantage in the Senate.
Like Cook, Menzies determined to address the situation, but knowing that the new proportional method of electing senators would make it exceedingly difficult to secure any sort of majority in the Senate.
Labor exploited its advantage in the Senate but eventually, early in 1951, there was a double dissolution; Menzies kept his majority in the House and secured a small margin over Labor in the Senate (32-28).
Menzies fully appreciated that proportional representation in the Senate made inter-house conflict much more likely than had been the case in the first half-century of the federation.
Under the proportional method, majorities, if they existed at all in the Senate, would be minuscule (as has proved to be the case).
Moreover, for the same reason, it became much less likely that a double dissolution would yield a majority of any kind in the Senate.
Over the years Menzies contemplated this dilemma. And he knew from the fate of legislation seeking to establish a Reserve Bank in the 1956-58 Parliament, the problem was not by any means hypothetical. A solution evaded him, as it has done everyone else who has tackled it.
Beginning with the Labor split in the mid-1950s, the two main sides of politics steadily lost their monopoly of Senate seats.
Surprisingly, the Whitlam Labor government elected in 1972 had no parliamentary strategy to deal with the inimical Senate situation it faced.
The double dissolution of May 1974, the accidental dissolution, was provoked by blockage of financial bills in the wake of Senator Vince Gair's appointment as ambassador to Ireland (a crude tactic seeking to give Labor an advantage in Queensland in up-coming half-Senate elections).
Still, it enabled Labor to secure some important legislation including Medibank in the joint sitting which followed.
The double dissolution in 1975 was sui generis, based on contested legislation of the ousted Labor government, which, being available, was used to resolve the parliamentary deadlock over the 1975 budget.
Early in 1983 Malcolm Fraser sprung a double dissolution based, inter alia, on a package of sales tax legislation. The double dissolution was driven by the government's need for "decisive control over both Houses of Parliament".
Fraser was trounced in the House and the Coalition suffered a net loss of three in the Senate.
The record is clear: the double dissolution, a minefield of technical traps, is a very uncertain weapon in the party battle.
J.R. Nethercote is adjunct professor, Canberra Campus, Australian Catholic University.