Writs for by-elections are signed and issued by the Speaker of the House of Representatives in accordance with the Australian Constitution and the Commonwealth Electoral Act 1918.

The AEC is required to deliver the election in accordance with writs and the Commonwealth Electoral Act 1918.

It is not required. Not by electoral laws or the Constitution.  

It has previously been stated by some that the absence of the Great Seal of the reigning British Monarch means that election writs are invalid, and by extension the election itself is invalid. This is incorrect.  

It is an offence under s 329 of the Electoral Act to publish information during the election period that is likely to mislead or deceive someone in relation to the casting of a vote.