Interview Panels comprise three members, a Panel Chair, a Judicial Member and an Independent Member.
Where a Selection Day is just an interview, you will normally be interviewed by a three person panel. If there is an interview and a role-play, there will often be a four person panel, including an additional Judicial member. The Panel Chair and Judicial Member will interview you, and the second Judicial Member and Lay Member will observe your role-play.
The interview will be structured to allow the Panel to obtain examples from you to show that you possess the qualities and abilities required. Interview questions will be tailored to your experience. The Panel may refer to the examples you gave on your application form, so when preparing you may wish to remind yourself what you said. The Panel will also have your references available to them at the interview stage.
The Selection Panel is not trying to trying to catch you out. They understand that interviewing may be a nerve-racking experience, and they will do their best to put you at ease.