The Coalition wants to resurrect a Howard-era immigration policy, and charge many of the people residing in immigration detention hundreds of dollars a day for being there.
The policy would apply to people awaiting deportation on character grounds, particularly convicted criminals who are not Australian citizens.
Federal Labor has indicated it is supportive of the idea, despite its national policy platform indicating it is opposed to cost recovery from detainees.
Under the policy, detainees subject to the fees would be charged $456.23 per day.
Some detainees spend years in immigration detention pursuing various avenues of appeal, meaning they could run up significant debts.
The previous policy, which was primarily being applied to asylum seekers, was scrapped by the Rudd government in 2009 for everyone except illegal fishers and people smugglers.
At the time, the then-Labor government argued it was both punitive and ineffectual, as very little of the debt being incurred was ever collected.
The costs of running the scheme were either higher than, or even with, the revenue brought in.
Between mid-2006 and mid-2008, about $54 million in debt was accrued, but just under $2 million was collected.
Questioned on Friday morning, Prime Minister Scott Morrison argued it was better than nothing.
"That's $2 million more than there was before," he said. "That's why it's important, it sends a very strong message.
Experts question capacity of government to collect debt
Immigration experts say any return to the policy of levying fees on those in immigration detention will likely incur the same problems the policy faced pre-2009: That is, the debts are very hard to collect.
Former senior Immigration Department official Abul Rizvi said that trying to gather money off non-citizens abroad was hard work.
"Most of the debts are incurred by people who have been deported from Australia," he said.
"And, as a result, we rarely made the effort to try to get the money back."
He said it was hard to see how the policy might be more successful now.
"I still see no evidence that it will actually increase debt collection," he said.
"It'll increase, in my view, administrative effort but not much more."
It is understood the policy would be targeted towards people the government views as having the capacity to pay debts, particularly those with Australian-based assets.
Refugee activist Ian Rintoul said the policy appeared designed to discourage detainees from pursuing legal appeals, as they would face an ever-growing debt.
"The one thing it will do is very, very likely influence people who are being detained — awaiting deportation on character grounds — from perhaps exercising their appeal rights," he said.
"Because it means [that], every day that they are in detention — even if they're going through the legal procedures that are available to them — they'll be racking up debt."
Immigration Minister Alex Hawke said those facing deportation should be leaving the country, not challenging their deportation in court.
"People need to consider very carefully, when they've come to Australia on a temporary visa as a privilege, and then violated our laws with a very serious offence, they should leave our country," he said.
"We don't expect them to sue us and continue to try [to] challenge that after their conviction.
