Advice gratefully appreciated re: interview

A position has come up in a school and there are a number of candidates from within the current staff considering applying.It is a management role.The present incumbent plucked a person out of nowhere the last time a position arose.The person chosen was the least qualified of the 4 candidates that applied back then but would be someone that would not upset the apple-cart in anyway and hence was the 'chosen one'.The fear now is that this same person will be 'fast tracked' again and that the staff considering applying would be wasting their time.'False' or 'dummy interviews' were held last time so as to fulfil legal formalities and who is to say that this will not happen again! The Union were very poor when alerted to this carry on last time and just stood back and let it happen even though they were informed quite early in the process and chose to ignore. No doubt the interview panel will be a 'safe' one as well.Should one bring up the subject of lack of equality,fairness and transparency while attending interview? It is about time we had whistle-blowers in the teaching profession.It would certainly get rid of a lot of cheats.