Should be the members of the staffing committee if the council have one. But if it is for a specialised role that one councillor has personal working experience of, then they should be added. For example if a council is recruiting someone to maintain land and plants, and a councillor had done that job in the past for a company or other authority they would be a good person to have in board. If the Mayor is not on the staffing committee then his/her inclusion should be challenged.