An historic 'Super Saturday' of federal by-elections is set to be held on July 28, but Labor is concerned this will leave voters in five seats without MPs for 79 days.
The seats of Braddon, Fremantle, Longman and Mayo are vacant because their MPs were found to be dual citizens and resigned from parliament, while the member for Perth resigned for family reasons.
Speaker Tony Smith told parliament on Thursday he would issue writs for by-elections on July 28, based on advice from the Australian Electoral Commission.
AEC commissioner Tom Rogers said the "optimal" July 28 date was based on two key factors - avoiding school holidays and allowing potential candidates to comply with new regulations under which they would voluntarily publicly declare they are not dual citizens.
However, he admitted the AEC had the ability to run elections - including a full federal election - on whatever date the government decided.
"The Australian Electoral Commission stands ready to conduct those events in accordance with your instructions on any legislatively appropriate date," he said in his advice to the Speaker.
Labor pointed out it would leave the five seats, four of which were held by the opposition, without members for 79 days, and land on the day of its national conference.
The new members won't be able to take up their seats until August 13 at the earliest.
"This deliberate delay is an insult to these communities who will be unrepresented for nearly three months," Labor deputy leader Tanya Plibersek said.
"It would also appear this has been deliberately designed to disadvantage the Labor Party, given our national conference is scheduled for that weekend."
Labor Party national president Mark Butler said the announcement stunk of interference by Prime Minister Malcolm Turnbull with the electoral commission.
"Our national conference is an important part of our policy process - and the fact the Liberal Party has deliberately sought to disrupt our democratic processes shows how desperate and pathetic they are," Mr Butler said in a statement.
Discussions are underway into deferring the conference until next year.
When former Nationals leader Barnaby Joyce resigned last year over his dual citizenship a by-election was called the same day for the soonest possible date.
The government is awaiting the Governor-General to sign off on a new regulation, which already has bipartisan support, to ensure all candidates must publicly declare they are not dual citizens or have any other bars under the constitution.
The vice-regal sign-off is expected on May 29, with the regulations expected to take two weeks for the AEC to implement.
Labor won't face a coalition candidate in Perth or Fremantle and is expected to hold the seats comfortably.
However the coalition has its sights set on the Labor seats of Longman and Braddon and the Centre Alliance-held seat of Mayo.
The vacancies aren't expected to impact significantly on parliament as it heads into the long winter break after June 28.
Australian Associated Press
