They generally receive free board, meals and pocket money in exchange for childcare and light housework duties.
WHAT IS MINISTERIAL DISCRETION UNDER MIGRATION LAWS?
Immigration minister has powers under migration laws to intervene in visa cases if they think it is in public interest to do so.
The minister decides what is in the public interest.
The minister is not legally bound to intervene or to consider intervening.
Ministerial interventions can be sought to overturn a decision by the Administrative Appeals Tribunal or in asylum seeker cases where a protection visa has been refused or cancelled.
Since 1989 immigration ministers have had the power to exercise personal discretion in visa cases.
The power was aimed being a "safety valve" for difficult cases that were outside the statutory visa criteria.
There has been a rising number of ministerial interventions. Under the Hawke and Keating governments immigration minister Gerry Hand made 81 interventions in two years while his successor Nick Bolkus made 311 in three years. Under the Howard government Philip Ruddock intervened 2513 times between 1996-2003.
In 2006-2007 the immigration department received 4000 requests for ministerial intervention.
Peter Dutton has intervened more than 450 times since he became minister at the end of 2014.
WHAT DOES MINISTER DUTTON SAY?
- His family does not employ an au pair and never has.
- Each year he makes hundreds of ministerial discretion decisions under the Migration Act.
- Cases are often brought to him by members of parliament of all political persuasions.
- He looks at individual circumstances around each matter.
- In two matters, young tourists came in on tourist visas but declared to airport officials they "intended to perform baby-sitting duties whilst they were here".
- A decision was taken by airport officials to cancel the tourist visas, detain the women and deport them.
- The minister, who says he did not personally know the women, granted the tourist visas based on their commitment not to work.
- The women did not overstay, and returned home.
The Senate instigated an inquiry into ministerial discretion in June 2003 after allegations were raised about the Howard Government's then-Immigration Minister Philip Ruddock's use of the power in four cases from 1998 onwards. Mr Ruddock was under fire over "cash-for-visa" allegations. There were claims visas had been granted through ministerial intervention to people who had made donations of up to $100,000 to the Liberal party or their associates.The inquiry was unable to get to the bottom of the saga because it was not given access to case files.
There were also reports Ruddock's successor Amanda Vanstone intervened to grant a suspected mafia figure a visa in 2005 after his relatives made donations to the Liberal Party.
In 2008, Rudd government immigration minister Chris Evans ordered an independent review into the ministerial discretion because he believed it gave him too much power and lacked transparency and accountability.
Evans adopted several recommendations aimed at restoring integrity and transparency.