18(1)In relation to the terms and conditions of the contracts of employment of employed constables, the Agency shall comply with rules or principles contained in any document issued to it for the purpose by the Secretary of State.E+W
(2)Rules or principles under sub-paragraph (1) may (in particular)—
(a)require the adoption of specified scales or ranges of pay or allowances;
(b)require a specified class of employed constable to be treated for specified purposes in the same way as a specified class of employee (whether of the Agency or not) or office-holder;
(c)require the approval of the Secretary of State for changes in the policy or practice of the Agency;
(d)require compliance with future rules or principles, including future rules or principles specified by a person other than the Secretary of State;
(e)make different provision for different purposes.
(3)In this paragraph “employed constable” means a member of the Agency's staff who is—
(a)a constable, and
(b)an employee of the Agency.