Each state and territory of Australia determines whether or not to use daylight saving time (DST). However, during World War I and World War II all states and territories had daylight saving by federal law, under the defence power in section 51 of the constitution.In 1968, Tasmania was the first state since the war to adopt daylight saving. In 1971, New South Wales, Victoria, Queensland, South …

https://en.wikipedia.org/wiki/Daylight_saving_time_in_Australia