The AEC is frequently asked about the procedure for setting polling dates for by-elections. The following edited extract from House of Representatives Practice, Canberra, 2001, has been reproduced here.
Whenever a vacancy occurs in the House of Representatives because of the death, resignation, absence without leave, expulsion or disqualification or ineligibility of a Member, a writ may be issued by the Speaker for the election of a new Member. A by-election may be held on a date to be determined by the Speaker or in his or her absence from Australia by the Governor-General in Council. The polling must take place on a Saturday.
If there is no Speaker or if the Speaker is absent from the Commonwealth, the Governor-General in Council may issue the writ.
A by-election writ may be issued by the Acting Speaker performing the duties of the Speaker during the Speaker's absence within the Commonwealth. A writ has been issued by the Chairman of Committees as Deputy Speaker during the Speaker's absence within the Commonwealth and the Chairman of Committees as Deputy Speaker has informed the House of the Speaker's intention to issue a writ.
There are no constitutional or statutory requirements that writs be issued for by-elections within any prescribed period. The following cases have occurred:
Notwithstanding that, Speakers have decided not to issue writs pending general elections, a suggestion that the Speaker should withhold issue for other purposes has been rejected.
A writ has been issued by the Governor-General between a general election and the meeting of a new Parliament consequent upon the death of an elected Member and when a Member has resigned to the Governor-General before the house has met and chosen a Speaker. Based on this procedure new elections have been held before the meeting of Parliament and after the meeting of Parliament.
In issuing a writ for a by-election Speakers normally follow the procedure set out below: