JPs are authorised to conduct private citizenship ceremonies.
The process is clearly explained in the following documents:
The Department of Internal Affairs points out that the application process must be initiated by the person applying for citizenship him/herself, not by the JP. The applicant must approach the Department to obtain the necessary documentation which he or she then presents to the JP.
Applications for privately conducted ceremonies are not approved automatically. They are considered on a case-by-case basis, taking into account the circumstances that have been outlined in the application.