Balance of power (parliament)

In parliamentary politics, the term balance of power may describe a parliamentary situation in which a member or a number of members of chamber are in a position by their uncommitted vote to enable a party to attain and remain in minority government, and the term may also be applied to the members who hold that position. The members holding the balance of power may guarantee their support for a government by either joining it in a coalition government or by an assurance that they will vote against any motion of no confidence in the government or abstain in such a vote. In return for such a commitment, such persons may demand legislative or policy commitments from the party they are to support. A person or party may also hold a balance of power in a chamber without any commitment to government, in which case both the government and opposition groupings may on occasion need to negotiate that person's legislative support.

The term itself is partially a misnomer of its misapplication from geopolitics in the 20th century and European politics in the 19th century which involved, for example, the assessment of the conditions of war following the Napoleonic campaigns across Europe (see Metternich).

In the 1940 federal election of the 74 seats in the House of Representatives, the United Australia/Country Coalition won 36 seats, the Labor Party won 32, the Non-Communist Labor Party won 4, and there were two independents, leaving the United Australia government of Robert Menzies without a majority in the lower house. The Coalition continued in government with the support of the two independents. The following year, the Non-Communist Labor Party, a breakaway Labor faction associated with former New South Wales premier Jack Lang, was readmitted to the Labor Party, and after the removal of Menzies by his own party, the independents in Parliament switched their support to Labor, allowing Opposition Leader John Curtin to form a minority government until his landslide reelection in 1943.

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