Australia's mandatory detention applies to people who enter on a visa and overstay their visa: https://humanrights.gov.au/resource-hub/by-resource-type/books/bo

Australia's mandatory detention applies to people who enter on a visa and overstay their visa: https://humanrights.gov.au/resource-hub/by-resource-type/books/books-large-contents/6.-australias-immigration-detention-policy-and-practice https://humanrights.gov.au/resource-hub/by-resource-type/boo... "Australian law requires the detention of all non-citizens who are in Australia without a valid visa (unlawful non-citizens). This means that immigration officials have no choice but to detain persons who arrive without a visa (unauthorised arrivals), or persons who arrive with a visa and subsequently become unlawful because their visa has expired or been cancelled (authorised arrivals). Australian law makes no distinction between the detention of adults and children."