Online histories bite Australian election candidates

Australian political parties have cut loose or chastised several of their own candidates for sexist, anti-Muslim, racist and homophobic behaviour less than three weeks before elections, with most falling victim to their own online histories.

The scandals surrounding candidates have become recurring distractions for Prime Minister Scott Morrison and opposition leader Bill Shorten this week as they attempt to sell their policies on the campaign trail ahead of the May 18 poll. 

A frustrated Morrison has suggested his conservative Liberal Party update its candid ate vetting processes to deal with the online generation.

Morrison on Thursday stood by Liberal candidate Jessica Whelan against accusations that she made anti-Muslim posts on social media.

Morrison said Whelan's social media comments appeared to have been doctored and a complaint had been made to police.

"I don't think it's hard to believe in this day and age that images can be doctored," Morrison told reporters. Whelan had earlier declined to answer reporters' questions about the posts.

Another Liberal candidate, Jeremy Hearn, was dumped by the party on Wednesday after a series of anti-Muslim comments came to light.

He wrote online in 2016 that taxpayers should not fund Muslim schools because they were "fomenting rebellion against the government."

In yet another case, Liberal candidate Peter Killin resigned from the party on Wednesday after secretly attacking gay government lawmaker Tim Wilson online in December and calling for party members to do more to prevent gays from being elected.

The centre-left opposition Labor Party has also been embarrassed by candidates it has endorsed. 

Wayne Kurnoth was forced to quit the party on Monday over anti-Semitic social media posts and conspiracy theories including that the world is secretly controlled by an alien race of Jewish lizard shape-shifters, mythological beings able to change their physical forms at will.

Labor candidate Luke Creasey apologised on Wednesday for sharing a rape joke and pornographic material on his Facebook page in 2012.

"It's been brought to my attention that some posts I shared on social media a number of years ago have been circulated," Creasey said. "They were stupid, immature and in no way reflect the views I hold today."

Steve Dickson, a candidate for the minor One Nation party, quit the election race on Tuesday after video of him groping and propositioning dancers in a US strip club was broadcast on national television.

Another One Nation candidate, Ross Macdonald, has since come under scrutiny after a newspaper on Wednesday published his social media posts of grabbing a woman's breast during a vacation in Thailand and other sexual images.

Some of the ill-fated candidates are thought to be victims of political enemies who have compiled dirt files and timed the release of the online indiscretions to maximise political gain.

Parties cannot replace dumped candidates because the ballot papers have already been printed and early voting began on Monday.