Australian Citizenship Instructions valid or invalid?

A recent decision of the Full Federal Court will be of interest to practitioners
http://www.judgments.fedcourt.gov.au/judgments/Judgments/fca/full/2019/2019fcafc0079
Minister for Home Affairs v G [2019] FCAFC 79 by reason of its discussion of the role of the ACI's (Australian Citizenship Instructions)
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