ON 18 DECEMBER 1985, the High Court of Australia delivered Kioa v West  HCA 81; (1985) 159 CLR 550 (18 December 1985).
The High Court recognized that an administrative decision maker has duty of acting fairly or according procedural fairness under the rules of natural justice.
A decision was made to deport Mr Kioa and his family back to Tonga on the grounds of him changing his address without notifying the department and engaging with Tongan illegal immigrants. Mr Kioa was given an opportunity to make submissions but was not informed of the adverse allegations.
The High Court held that a failure to disclose to Mr Kioa the adverse allegations and allow him the opportunity to respond was a failure to afford procedural fairness.
As a fundamental principle of natural justice, an opportunity must be given to deal with adverse information that is credible, relevant and significant to the decision to be made.