After a high court decision in November that led to the release of more than 100 people in immigration detention, the Labor government has passed legislation designed to toughen Australia’s immigration law. Termed ‘preventative detention’, these new powers allow the government to send some high-risk non-citizens to prison – even though they haven’t committed a new offence. Chief political correspondent Paul Karp tells Laura Murphy-Oates about the moral and legal minefield surrounding these new powers You can support the Guardian at theguardian.com/fullstorysupport