Opposition parties are expected to grill the Australian government over the awarding of $420m in security contracts to a little-known firm whose registered address is a beach shack on Kangaroo Island.
Paladin Group is being paid the sum over two years to guard asylum-seekers Australia keeps offshore on Manus Island in Papua New Guinea.
One of the company's directors is facing unrelated serious fraud charges, and another is barred from entering PNG, yet Paladin's contract was renewed last month in a tender process that does not appear to have had any other applicants.
"I think the very biggest question to be answered is - how on earth did this tiny unknown company with no track record ever get $423m in contracts from the Australian taxpayer?" Labor Senator Murray Watt said.
"You would normally expect contracts of that value to go to large, well-established companies with a track record and with directors with some reputation."
The Paladin contract came to light in a story by the Australian Financial Review last week.
The story also reported the Department of Home Affairs made an advance payment of $10 million to Paladin because the company did not have enough money to begin the contract.
Government must show due diligence, crossbenchers say
South Australian crossbench senator Stirling Griff said he wanted to see a detailed breakdown of the contract and said the government must show that due diligence was done in the tender process and that the company was providing adequate services.
"If you actually do the calculations, it averages out at $1600 a day to house each and every refugee, not including food and welfare services, which is more than double what you pay in a five star hotel," he said.
"So it doesn't appear to represent value for money in any respect."
Home Affairs Minister Peter Dutton has said he had "no sight" of the tender process.
But Greens immigration spokesman Nick McKim said that was not good enough.
"Hundreds of millions of dollars have been awarded to a shonky company and Peter Dutton's claiming he knew nothing," Senator McKim said.
"Well if he didn't know, he should have.
"I mean you couldn't make this stuff up and it's exactly why we need a federal ICAC, so matters like these can be properly investigated."
Attorney-General Christian Porter told the ABC's Insiders program the arrangement had been subject to a "full independent Commonwealth procurement process" and that such procurement processes were often kept at arm's length from the minister.
He said the sums of money involved needed to be seen in context.
"The reality is that doing these types of things offshore in Papua New Guinea and in Nauru is a very costly exercise," Mr Porter said.
"But in exacting that costly exercise we have managed to stop the inhumane outcome of 1200 people dying at sea, 50,000 people arriving illegally and at its peak 20,000 people being held in immigration detention in Australia."