7   Categories of employment

(1)  Staff may be employed in a Department in the following categories:

(a)  officers—being persons employed in chief or senior executive positions or other staff positions in the Department,

(b)  temporary employees—being persons employed to carry out work in the Department on a temporary basis,

(c)  casual employees—being persons employed in the Department on a casual basis.

(2)  Temporary employees may be employed in following subcategories:

(a)  Departmental temporary employees—being persons employed under Part 2.4 to carry out work in a Department,

(b)  special temporary employees—being persons employed under Part 2.5 to carry out work for a political office holder.

(3)  The usual basis for the employment of staff in a Department is to be the employment of officers.

(4)  Subsection (3) does not apply to the employment of staff for the purpose of carrying out work for a political office holder.