The contract leaves about $12 million for the rest of the program, including an advertising blitz in multiple languages to ensure that any Victorian knows to safely dispose of a machete if they have one.

The Department of Justice and Community Safety has translated Facebook ads into Spanish, Dari (an official language of Afghanistan), Italian, Vietnamese, simple and traditional Chinese, Punjabi, Greek, Turkish and Arabic.

A bin outside Prahran police station.

A bin outside Prahran police station.Credit: Alex Coppel

G4S runs Mount Gambier Prison in South Australia and Port Phillip Prison in Victoria, which is closing at the end of the year. Mount Gambier Prison has metal fabrication facilities.

The Age asked G4S to confirm which prison or prisons the bins were made in, including whether the security company had subcontracted the manufacturing to other private prison operators. G4S declined to comment.

Information about what companies use prison labour in Victoria is held notoriously tight, even in publicly run centres. The government has labelled this information commercial in confidence, and has previously argued the release of such details could harm prisoners’ post-release employment prospects.

The premier’s office and the Department of Justice and Community Safety declined to comment when asked about the use of prison labour to make the blue bins, saying the details were commercial in confidence.

Corrections Minister Enver Erdogan was asked in state parliament last month whether any of the bins had been made in prisons. He didn’t give a direct response but said prisons provided employment pathways including through metal fabrication.

He later told Limbrick that Corrections Victoria did not make the bins, in a message seen by The Age. Corrections Victoria does not manage private prisons.

Limbrick had been sent a photo of several bins piled up outside a Laverton North facility, which his team geolocated using Google Maps Street View to identify the site as a prisoner transport centre and G4S training facility. The Age confirmed the location in the same way.

Limbrick also sought his own quote, which put the cost of producing a bin at $3700, and had no issue with the government using cheaper prison labour to keep costs at $2400.

“If the government was just up-front about these things and explained it, there would not be this needless speculation,” he told parliament last week.

Libertarian MP David Limbrick.

Libertarian MP David Limbrick.Credit: AAP

Prisoners are paid between $7.05 and $9.70 a day, well below normal worker entitlements.

Justice Reform Initiative executive director Dr Mindy Sotiri said the hourly pay for prison labour in most jurisdictions was less than $2 an hour and more than 60 per cent of prisoners were released into unemployment because of the stigma and barrier of a criminal record.

“While opportunities for employment currently exist in many prisons around Australia, these opportunities rarely provide the skills and qualifications that translate into genuine pathways into sustainable post-release employment,” Sotiri said.

“The key issue is whether this kind of prison labour actually provides opportunities for people in prison to develop skills, training and qualifications that will support them to transition to life on the outside.”

Hundreds of machetes have been handed in since the amnesty program began on September 1.

Limbrick, in a statement to The Age, said there was massive interest in the bins.

“My social media posts are racking up hundreds of thousands of views and people are calling in and sending us tips,” he said.

“This is not the most pressing issue in Victoria by a long shot. But I think government secrecy has fuelled the interest. People also see this as a rare opportunity to get to the bottom of how government projects work and why they cost so much.”

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