It is sometimes much harder to determine the difference than you would think - the lines are often blurred. However, a court may make a determination as to whether the party is an employee or independent contractor based on all the facts, and not just what the employer calls him. There are a range of tests, including the control test (does the employer exercise control and supervise the employee?), the organisation test (is the employee part and parcel of the employer's organisation or is he only an accessory to it?) and the dominant impression test (which is a broader test drawing on a variety of factors).
Refer to: http://www.labourprotect.co.za/Employee_&_Independent_Contractors.html