Without prejudice to section 7 of the Local Government and Housing Act 1989 (which provides for the appointment of staff of local authorities to be made on merit) and to any requirement in any other enactment as to the considerations to which they may or may not have regard in making appointments, an education authority who are considering an appointment of a teacher shall not exclude any person from consideration for such an appointment on the ground that—
(a)he is not employed by that education authority; or
(b)he is or is not employed by a particular employer or class of employer; or
(c)he is not currently employed as a teacher.