Australia's government is reviewing 201 cases of possible wrongful detention under its strict immigration policy, in the wake of several high-profile cases.
Australian citizen Vivian Alvarez was mistakenly deported
Immigration Minister Amanda Vanstone said she wanted a "clean slate".
Two women are seeking compensation for their treatment as illegal immigrants, and an infant has just been freed after spending her entire life in detention.
The cases have prompted a rare revolt from the government's backbenchers over its tough immigration policy.
Government rebels, led by Victoria state politician Petro Georgiou, are calling for a conscience vote over the policy of indefinitely detaining all illegal immigrants.
Ms Vanstone said every one of the 201 cases would be scrutinised, "because the department is determined to recognise what problems it may have and to change".
A number of controversial immigration cases have come to light in recent weeks.
They include those of Cornelia Rau, a German-born Australian resident, and Vivian Alvarez, a Philippines-born Australian citizen.
Ms Rau, whom her family says is mentally ill, was held for 10 months in a detention centre for illegal immigrants after going missing from a psychiatric ward in Sydney last year. She told the authorities she was a German woman named Anna Schmidt.
Ms Alvarez, who is disabled, was erroneously deported to the Philippines four years ago. The government sent a social worker to Manila on Monday to bring her back, but her lawyers first want Canberra to agree sufficient compensation to pay for her care.
Spotlight on children
And on Monday, three-year-old Naomi Leong and her Malaysian mother Virginia were released from Sydney's Villawood detention centre, where Naomi had been held since she was born.
Psychiatrists say Naomi has mental health problems, and was reportedly banging her head against the centre's walls.
Sixty-seven children remain in Australia's detention centres.
But Prime Minister John Howard ruled on Wednesday that a baby born to a Vietnamese couple being held at an offshore centre, for illegal entry, would not be taken into detention.
He said Michael Andrew Tran, who was born on Monday night, would live in community accommodation in Australia.
A spokeswoman for Mr Howard later said the government had no immediate plans to return the couple to detention, on Christmas Island.