Independent candidate for Hume, Penny Ackery, has expressed her disgust at 'fake' and illegal signs posted throughout the electorate stating that she was aligned with The Greens.
One was placed on the fence of Saint Patrick's Cemetery, Goulburn, where her husband, John, was buried just weeks ago.
"It's despicable and shows the lengths some people will go to in politics," Ms Ackery said.
"It's something we need to stop happening and clean up...I was extremely upset when I found out one had been placed at the cemetery, which was disrespectful anyway. It wasn't just any cemetery but the one where I buried my husband."
Her team removed them and reported the matter to Narellan Police, which referred it to the Australian Electoral Commission (AEC).
The AEC confirmed it was investigating a range of unauthorised candidate corflute signs that had appeared across a number of electoral divisions. They had also appeared in Warringah, Mackellar and Hughes electorates in Sydney and suggested that The Greens were backing independent candidates.
They were in breach of Commonwealth electoral laws as they did not contain an authorisation statement, the AEC said.
"This is a very serious matter and we are exploring all avenues possible to get to the source of the signage," Electoral Commissioner Tom Rogers said.
The matter has been referred to the Electoral Integrity Assurance Taskforce for investigation. Information is being sought directly from relevant entities and being examined in an effort to determine the source.
In some cases, Ms Ackery's signs were specially made to state: 'Penny Ackery and The Greens' with the latter party's logo. She said her signs were also stolen throughout the electorate and placed next to the illegal ones.
The independent described it as "dirty politics" and said the money spent on the signage would have been better devoted to a charity.
She said they had also been placed on public places, which was illegal in itself.
Goulburn Mulwaree Council has cracked down on signage as well, particularly in public places or where it was regarded as a driver distraction.
Ms Ackery said the council had impounded some of her signs which were posted before the election was called, but not since. No fines had been issued but officers reminded all parties of their obligations.
"The council has acted well within the space of the law. They've been diligent and their rangers have had to waste an awful lot of time on people putting up illegal signs," she said.
"I take my hat off to the tenacity and patience of all councils."
However she decried the theft of one from an elderly Goulburn woman's yard by "two hooded people" one night.
A Goulburn Mulwaree Council spokesman said about 350 signs had been impounded since the beginning of the election campaign.
"All parties have been notified individually periodically, and asked to collect their impounded signage by a certain date. No penalty infringement notices have been issued for unauthorised signage to date," he said.
The council has the power to issue a $100 impoundment fee per item under its fees and charges. None have been issued so far.
Meantime, Labor campaign worker Anna Wurth-Crawford said some of candidate Greg Baines' corflutes had been stolen from private properties in Goulburn and around Crookwell where they'd been legally placed, with the owner's permission.
"It's very unfair and undemocratic. We haven't touched anyone else's but people think it's okay to take ours down," she said.
United Australia Party campaign worker, Peter Clinch, said about 150 signs promoting candidate Garry Dollin had been stolen from around the Goulburn region. It has bee reported to police.
"We're lucky to get a sign to stay there for 24 hours," he said.
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