The Conflict Between Visa Cancellation or Refusal on Character Grounds and Australia's Non-refoulement Obligations

Suppose you have a client who does not satisfy the character test because she/he has a substantial criminal record.
Suppose also that it has been determined by the Tribunal that the client is owed non-refoulement obligations on complementary protection grounds.
In these circumstances, if the Minister exercises powers under section 501A(2) of the Migration Act to set aside the decision of the Tribunal and refuses to grant a protection visa, is there any legal theory available to challenge the Minister’s actions?
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