Why was Whitlam sacked and not just a double dissolution called?

Thanks Tom, that is a very complex question! A number of events led to the dismissal of Prime Minister Gough Whitlam and his government.

On 15 October 1975, the Leader of the Opposition, Malcolm Fraser announced the opposition would block the government’s supply or money bills in the Senate until an election was called. Fraser claimed Whitlam led ‘the most incompetent and disastrous government in the history of Australia.’ He said the opposition would ‘use all the constitutional opportunities available’ to force an election to be held so the people could decide. Whitlam said he would not be ‘forced’ to an early election.

On 11 November, the Governor-General, Sir John Kerr, decided the only way to break this deadlock was to use his reserve powers and dismiss Whitlam and his government. It is the first and only time the Governor-General has dismissed a prime minister who had the support of a majority of members in the House of Representatives.

Kerr appointed Fraser as caretaker prime minister on the condition he:

• guarantee the supply bills would pass the Senate
•  request a double dissolution election.

The supply bills were passed that afternoon and Fraser then asked the Governor-General to dissolve both houses of Parliament so a federal election could be held. To this day, some people still debate whether the Governor-General had the power to dismiss the prime minister.