Questions are being asked about a rush to impose mandatory minimum one-year prison sentences for immigration detainees who resist deportation.
Labor tried to ram new laws through parliament this week but was railroaded by the coalition, Greens and crossbench in the Senate on Wednesday, which voted to send its bill to an inquiry that will report on May 7.
The legislation, which passed the lower house on Tuesday, also included penalties of up to five years behind bars and a $93,000 fine. In addition, the minister would have the power to ban visa classes for countries that don't accept deportees.
Opposition home affairs spokesman James Paterson said it was difficult for the coalition to support its immediate passage without proper scrutiny in case of unintended consequences.
"In light of that, it's very difficult for the coalition to support such a rushed passage of this legislation," Senator Paterson told reporters in Canberra.
Concerns include that banning visas from a particular country could lead to an increase in people trying to sail to Australia using people smugglers.
The laws come ahead of a High Court decision involving an Iranian citizen known as ASF17 who has made a bid for freedom that is set to come to a head on April 17.
The man is seeking to have an earlier High Court ruling, that indefinite immigration detention is illegal for those who cannot be returned to a third country, also cover detainees who refuse to co-operate with their deportation.
Wednesday is parliament's last sitting day before the ruling.
When asked if the laws were needed to respond to ASF17, Home Affairs Department legal counsel Clare Sharp said the bill "does not respond to the points of law being tested" in the case.
But it did deal with the same cohort who would be affected by the outcome of the case regardless of the decision, she added.
Department secretary Stephanie Foster was asked the same question and said it was "really important that we have a broad-base system with integrity" to respond to court cases as they arise.
Senator Paterson said the opposition would support parliament being recalled if the government made the case for its urgency or passed legislation after the decision.
Home Affairs Minister Clare O'Neil initially refused to comment directly but later said the court case "does show that it's important that we have these powers" but it wasn't the only reason the laws were being moved.
"It's very important that the Australian government move towards running a more orderly migration system."
Asked repeatedly why the legislation needed to be passed without debate or scrutiny, she said it was important it was passed efficiently to strengthen the migration system and the urgency was "blindingly obvious".
But she didn't offer a reason for why the powers were needed six weeks earlier, before the inquiry had a chance to examine unintended consequences in draft legislation that was only completed on Friday.
Independent MP Monique Ryan raised concerns the legislation could, if the government makes a mistake when determining if someone is a refugee or not, mean they could be deported to a country where their lives were at risk.
But Ms O'Neil said the laws would only apply to people who had exhausted all legal avenues to prove they were a refugee.
"They have lost every appeal, they have lost every court case and yet as it stands today, the Australian government does not have a power to compel those people to co-operate," she said.
However, the Human Rights Law Centre argued the fast tracking of some of these applications meant they wouldn't be fully considered.
While it won't apply to people found to be refugees, the concern stemmed from people who had strong claims but didn't have a fair hearing or review, the council's Refugee Council of Australia CEO Paul Power added.
The Greens have attacked the bill for demonising asylum seekers.
Australian Associated Press
