Leadership spill

In Australian politics, a leadership spill (or simply spill) is a declaration that the leadership of a parliamentary party is vacant, and open for re-election. A spill may involve all leadership positions (leader and deputy leader in both houses), or just the leader. Where a rival to the existing leader calls for a spill, it may also be called a leadership challenge.

When a leadership vacancy arises due to the voluntary resignation or death of the incumbent, the resulting leadership election is not a leadership spill. Therefore, the election for the leadership of the Liberal Party of Australia after the disappearance of Harold Holt was not a leadership spill despite having four candidates.

In Australian English the use of "spill" in this context has a long history with its first recorded appearance traced to a Canberra Times article dated 20 August 1945.

A leadership election may result in a new leader, or may confirm the status quo. If the party in question is in government, the election of a new leader will result in a new Prime Minister, Premier or Chief Minister; if the party is the opposition, the election of a new leader will result in a new Opposition Leader.

There were 72 leadership spills between 1970 and 2015, which became increasingly common in the early 21st century - none in the 1960s, 10 in the 1970s, 18 in the 1980s, 13 in the 1990s and 31 between 2000-2015. They are three times more likely to occur when a party is in opposition compared to when it holds government. The frequent leadership spills and political instability in the 21st century - which saw five Prime Ministers between 2010 and 2015 - has led to Australia being dubbed "coup capital of the democratic world".

In the Westminster system of government, the leader of the party which forms Her Majesty's Government becomes the Prime Minister, while the leader of the largest party not in government becomes leader of the Opposition. Contenders for the role of leader of a major party usually (but not always) come from the cabinet or shadow cabinet.

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