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[Olive]

If a person does not pass the "character test" they can be deported. Here's a brief summary:

Section 501 of the Migration Act 1958 lists a variety of reasons why someone may not pass the character test. Subsection(6) of section 501 has the full list of reasons, but examples include:

because the person has a substantial criminal record
because the person may represent a danger to the Australian community
because the Minister is satisfied the person is not of good character due to their past and present criminal or general conduct.

So this entitles the Australian government to export its social problems to their countries of origin, which then have to deal with the fallout, disruption and inevitable new gang networks.