THE COURT. These are applications for an order nisi for a writ of prohibition directed to the Honourable John MacBean, a Deputy President of the Australian Industrial Relations Commission (the Commission), prohibiting him from further participating in the hearing and determination of certain proceedings before a Full Bench of the Commission. The central principle involved in the applications is well settled. It is that a judge or person obliged to act judicially in the discharge of the functions of a public tribunal should not sit to hear a matter if, in all the circumstances, a party or the public might entertain a reasonable apprehension that she or he might not bring an impartial and unprejudiced mind to the resolution of the question or questions in it. (See, eg, Livesey v New South Wales Bar Association - [1992] HCA 30 - HCA 1992 case summary — Zoe