Visa Cancellation and NZ Citizens: The Right Approach?

Is the visa cancellation regime under the Migration Act too harsh?
Does it effectively impose “double punishment” on offenders by making them subject to removal from Australia in addition to whatever sentence of imprisonment they receive?
Should someone who has committed an offence spend a longer time in immigration detention – where they have lost their liberty as effectively as if they were in prison serving a custodial sentence – for a longer period of time than they have been incarcerated for the original offence?
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